Chevrolet 1974 Light Duty Truck Service Manual

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Page 2 Duty Trucks. Procedures involving dis assembly and assembly o f major components for these vehicles are contained in the 1974 Chevrolet Passenger Car and Light Duty Truck Overhaul Manual. Wiring diagrams for 1974 trucks are contained in a separate Wiring Diagram Booklet.
Page 3 SECTION INDEX SECTION NAME GENERAL INFORMATION AND LUBRICATION HEATER AND AIR CONDITIONING BODY FRAME FRONT SUSPENSION 4-WHEEL DRIVE REAR SUSPENSION 1974 AND DRIVELINE BRAKES LIGHT DUTY ENGINE ENGINE COOLING TRUCK FUEL SYSTEM 1MISSION CONTROL (SERIES 10-30) SYSTEMS ENGINE ELECTRICAL CHASSIS SERVICE CLUTCH AND MANUAL TRANSMISSION MANUAL...
Page 5: General Information
SECTION 0 GENERAL INFORMATION AND LUBRICATION CONTENTS OF THIS SECTION General Information..............0-1 Lubrication..................0-5 GENERAL INFORMATION INDEX Model Line U p............... 0-1 Service Parts Identification Plate......... 0-3 Truck Model Designation..........0-1 Keys and Locks............... 0-3 Vehicle Identification Number and Rating Plate..0-1 Emergency Starting............
Page 6 V = V8- Y = V8- stamped on Front of Right Axle Tube. D IVISIO N Z = V8- MODEL YEAR C = CHEVROLET 4 = 1974 for all T = GMT Series. Transmissions • 3-Speed Transmission Unit Number Located on...
Page 7 GENERAL INFO RM ATIO N AND LUBRICATION • The battery in the other vehicle must be of the same S E R V I C E P A R T S I D E N T I F I C A T I O N 12 volts, and must be nominal voltage, negatively...
Page 8 0 -4 GENERAL INFORM ATIO N AND LUBRICATION on the ground for distances up to 50 miles at speeds of To Jump Start: less than 35 MPH. The engine should be off and the 1. Position the two vehicles so they are touching.
Page 9: Table Of Contents
GENERAL INFO RM ATIO N AND LUBRICATION VEHICLE LOADING LOADED-M AXIM UM GVWR: 6000-LBS. Vehicle loading 4must be controlled so weights do not FRONT GAWR: 3250 LBS. REAR GAWR: 3582 LBS. exceed the numbers shown on the Vehicle Identification Number and Rating Plate for the vehicle. In trailer hauling applications, the vehicle rear end weight at the ground with trailer attached must not exceed the "Maximum Rear End Weight at Ground"...
Page 10: Engine
0-6 GENERAL INFORM ATIO N AND LUBRICATION The time or mileage intervals for lubrication and NOTE: Non-detergent and other low quality maintenance services outlined in this section are oils are specifically not recommended. intended as a general guide for establishing regular maintenance and lubrication periods.
Page 11: Drive Belts
GENERAL IN FO R M ATIO N AND LUBRICATION effectively and economically solve certain specific When the air cleaner is removed backfiring can problems without causing other difficulties. For example, cause fire in the engine compartment. if higher detergency is required to reduce varnish and NOTE: Under prolonged dusty driving sludge deposits resulting from some unusual operational conditions, it is recommended that these...
Page 12: Manual Transmission
0-8 GENERAL INFORM ATIO N AND LUBRICATION 4. Remove dipstick and wipe clean. as shown in the following table. (For vehicles normally operated in Canada, use SAE 80 GL-5 Gear Lubricant.) 5. Reinsert dipstick until cap seats. 6. Remove dipstick and note reading. If oil level is at or below the ADD mark on the dipstick, Outside Temperature Viscosity Lubricant To Be Used...
Page 13: Brake Master Cylinder
GENERAL INFO RM ATIO N AND LUBRICATION BRAKE MASTER CYLINDER Check master cylinder fluid level in both reservoirs every 6,000 miles or 4 months. If the fluid is low in the reservoir, it should be filled to a point about 1/4" from the top rear of each reservoir with Delco Supreme No.
Page 14: Four Wheel Drive
0 -1 0 GENERAL INFO RM ATIO N AND LUBRICATION For exposed surfaces, such as door checks, door lock NOTE: A special needle nose grease gun bolts, lock striker plates, dovetail bumper wedges, etc., adapter for flush type grease fitting is apply a thin film of light engine oil.
Page 15 GENERAL INFORMATION AND LUBRICATION 0-11 COMPLETE VEHICLE MAINTENANCE SCHEDULE Item When To Perform Services Services (M o n th s or M ile s, Whichever Occurs First) (For Details, See Numbered Paragraphs) Every 4 months or 6,000 miles Chassis Lubrication *AFluid Levels 'Engine Oil Air Conditioning System...
Page 16 0-12 GENERAL INFORMATION AND LUBRICATION 4. AIR CONDITIONING—Check condition of air EXPLANATION OF COMPLETE conditioning system hoses and refrigerant charge at VEHICLE MAINTENANCE sight glass (if so equipped). Replace hoses and/or refrigerant if need is indicated. SCHEDULE Presented below is a brief explanation of each of the 5.
Page 17 GENERAL INFORMATION AND LUBRICATION 0-13 wheel or seat while driving at normal highway should be made by the owner (items a thru u). These checks should be made regularly during speeds. operation, at no greater interval than 4 months or h.
Page 18 Check brake pads and condi emission compliance and idle quality have been preset tion of rotors while wheels are removed during tire by Chevrolet. Plastic idle mixture limiters have been rotation. (Note below regarding more frequent installed on the idle mixture screws to preclude checks also applies to disc brakes.)
Page 19 GENERAL INFORMATION AND LUBRICATION 0-15 using a tester. Replace the PCV valve at 24-month At 24 month or 24,000 mile intervals on all 10 Series or 24,000 mile intervals, blow out PCV valve hose vehicles, and on 20 Series Suburban, Chevy Van and with compressed air and replace the filter.
Page 20 0-16 GENERAL INFORMATION AND LUBRICATION RECOMMENDED FLUIDS LUBRICANTS USAGE FLUID/LUBRICANT FLUID/LUBRICANT USAGE Hood hinges Engine oil G M power steering fluid Part No. Power steering system and pump reservoir 1050017 or equivalent— if not a v a il A utom atic transmission shift Engine oil able use D E X R O N ®...
Page 21 GENERAL INFORMATION AND LUBRICATION 0-17 Lubrication Type of Lubrication Points Quantity Remarks Lubrication Period Lower Control Arms 6,000 Miles Chassis Lubricant 4 places as required Upper Control Arms 6,000 Miles Chassis Lubricant 4 places as required Upper and Lower Control Chassis Lubricant 6,000 Miles 4 places as required...
Page 22 0-18 GENERAL INFORMATION AND LUBRICATION Lubrication Type of Quantity Remarks Lubrication Points' Lubrication Period See Vehicle A ir Cleaner 12,000 Miles Maintenance Schedule D istributor — L-6 24,000 Miles Replace Cam Lubricator* D istributor - V-8 24,000 Miles Replace Cam Lubricator* Control Linkage Points 12,000 Miles...
Page 23 GENERAL INFORMATION AND LUBRICATION 0-19 Lubrication Type of Lubrication Points Quantity Remarks Period Lubrication Control Arm Bushings and Ball Joints 6.000 Miles Chassis Lubricant 12 places as required Tie Rod Ends 6,000 Miles Chassis Lubricant 4 places as required 2 fittin q s each side Wheel Bearings 24,000 Miles Whl.
Page 25 HEATER AND AIR C O N D ITIO N IN G 1A-1 SECTION 1A HEATER AND AIR CONDITIONING CONTENTS OF THIS SECTION 1A-1 Standard Heater Auxiliary Heater 1A-15 1A-19 Air Conditioning STANDARD HEATER INDEX General Description..........Center Distributor Duct - G Models....1A-6 1A-1 ..
Page 26 DASH BLOW ER AIR D O O R DEFROSTER CORE M O T O R PANEL D O O R OUTSIDE AIR FROM C O W L PLENUM CHAMBER LEFT TO RIGHT TO DEFROSTER TEMPERATURE FLOOR FLOOR OUTLETS D O O R OUTLETS OUTLET Fig.
Page 27 HEATER A D EFR O STER A S M H EA TER & D EFR O S TE R A S M (H E ATE R IN OFF P O S IT IO N ) A IR OUTLET A IR O U T LE T VIEW A VIEW B STE E R IN G...
Page 28: Theory Of Operation
1A-4 HEATER AND AIR CO NDITIO NING THEORY OF OPERATION TURE door in the heater distributor assembly. All BLOWER AND AIR INLET ASSEMBLY incoming "outside" air is directed around the heater core The blower and air inlet assembly draws outside air in the COLD position or through the core in the HOT through the outside air inlet grille located forward of the position.
Page 29 HEATER AN D AIR C O N D ITIO N IN G 1A-5 the system. Moving the lever to the right (toward Temperature Lever HEATER) opens the air door with the AIR door being This lever controls the positioning of the TEMPERA fully open at the HEATER position.
Page 30: Center Distributor Duct - G Models
1A-6 HEATER AND AIR CO NDITIONING Fig. 5-Heater Distributor Assembly-C-K Models 3. Remove the nuts from the distributor duct studs and pull the duct rearward out of the heater case projecting into the engine compartment. retainer. 4. Remove the glove box and door assembly. 6.
Page 31: Left Distributor Duct - G Models
HEATER AND AIR C O N D ITIO N IN G 1A-7 Fig. 7-Heater Hose Routings 2. Unsnap the engine cover front latches. Remove the LEFT DISTRIBUTOR DUCT - G Models two cover to floorpan screws and remove the cover. Replacement (Fig.
Page 32: Control Assembly
1A-8 HEATER AND AIR CO NDITIONING LEFT DISTRIBUTOR DUCT HEATER CORE CASE Fig. 8-Distributor Ducts-G Models screws and carefully lower the control far enough to CONTROL ASSEMBLY gain access to the bowden cable attachments. C-K Models Care should be taken to prevent CAUTION: kinking the bowden cables while lowering the Replacement (Fig.
Page 33 HEATER AN D AIR C O N D ITIO N IN G 1A-9 Fig. 9-Defroster Outlets 7. Remove cable from retaining clip and remove cable assembly. 8. To install, reverse Steps 1-7 above. Be careful not to kink the cable CAUTION: during installation.
Page 34: Blower Switch
1A -10 HEATER AND AIR CO ND ITIO NIN G cable. Place protective tape around the cable BLOWER SWITCH mounting tab and attached wire and carefully pull the cable from the vehicle. Remove the tape and C-K Models disconnect the 4' piece of wire. Replacement (Fig.
Page 35 HEATER AND AIR C O N D ITIO N IN G 1A-11 DIAG NO SIS TROUBLE CAUSE AND CORRECTION T e mp e r a t u r e o f h e a t e r a i r a t o u t l e t s t oo low t o h e a t up p a s See "...
Page 36 1A -12 HEATER AND AIR CO NDITIONING I N S U F F I C I E N T HEAT D I A G N O S I S Position the controls so that the: Temperature lever is on fu ll heat. Selector or heater lever is on Heater.
Page 37 HEATER CI RCUI T D I A G N O S I S * BLOW ER M O TO R IN O P E R A T IV E (A N Y SPEED) I ---- Check fuse in fuse panel. FUSE BLOW N FUSE OK The fo llo w in g tests should be made w ith...
Page 38 1A -14 HEATER AND AIR C O NDITIO NING BLOWER MOTOR < g RESISTOR DASH 14B LBL STR- [-J“ 3 d P — 14 BRN 14B ORN STR 14B LBL STR — 14B ORN STR--------- ----------14 BRN----------- 14B ORN STR--------- BLOWER SWITCH I C O &...
Page 39 HEATER AND AIR C O N D ITIO N IN G 1A-15 AUXILIARY HEATER INDEX General Description..............1A-15 Controls..................1A-15 Component Replacement and Repairs........1A-17 Diagnosis..................1A-18 GENERAL DESCRIPTION An auxiliary heater is available as a dealer installed This valve must be operated manually-"on" for cold accessory to provide additional heating capacity for the weather, "off"...
Page 40 1A-16 HEATER AND AIR CO NDITIONING AUXILIARY HEATER (110" W.B. WITH REAR SEATS) EXISTING HEATER CONTROL SWITCH AUXILIARY HEATER 110" W.B. WITHOUT REAR SEATS) (ALL 125" W.B. MODELS) WATER VALVE Fig. 16-Auxiliary Heater Installations (G Models) INSTALL VALVE WITH ARROW POINTING A W A Y FROM TEE.
Page 41 HEATER AN D AIR C O N D ITIO N IN G 1A-17 RESISTOR EXISTING HEATER BLOWER SWITCH C-K MODELS FUSE PANEL RESISTER VIEW A FUSE G-MODELS PANEL BLOWER SWITCH Fig. 19-Control and Resistor Mountings COMPONENT REPLACEMENT AND REPAIRS Since a detailed list of installation instructions is 1-1/2"...
Page 42 1A -18 HEATER AND AIR CO NDITIO NING D IA G N O SIS Refer to the "Standard Heater" section of this manual inoperative on C-K models (equipped with for diagnostic information; see Electrical Diagram Overhead Air Conditioning), check that the Figure 21.
Page 43 HEATER AND AIR C O N D ITIO N IN G 1A-19 AIR CONDITIONING INDEX General Description............ 1A-22 Collision Procedure-All Vehicles......1A-60 Four-Season System (C-K Models)......1A-22 Component Part Replacement-Four-Season C60 System (G Models)........... 1A-22 System— C-K Models..........1A-61 Overhead Systems (C-K-G Models)....... 1A-22 Condenser..............
Page 44 1A-20 HEATER AND AIR C O N D ITIO N IN G Expansion Valves............1A-79 Blower Assembly............1A-83 Evaporator Core............1A-80 Expansion Valve, Evaporator Case or Core..1A-83 Resistor................. 1A-80 Thermostatic and/or Blower Switches....1A-84 Blower Switch.............. 1A-81 Resistor................1A-84 Rear Blower Relay............ .1A-81 Fuse.................1A-84 Tie Relay..............1A-81 Diagnosis..;..............
Page 45 EVAPORATOR CORE BLOWER & SHROUD EVAPORATOR ASM R.H. OUTLET CONTROL □ R.H. OUTLET VIEW A CENTER OUTLET L.H. OUTLET A IR C O N D IT IO N IN G O VERHEAD SYSTEM AIR INLET VALVE PLENUM VALVE HEATER CORE BLOWER &...
Page 46 1A-22 HEATER AND AIR C O N D ITIO N IN G GENERAL DESCRIPTION increases the resistance of the thermister to 400 ohms, FOUR-SEASON SYSTEM (C-K MODELS) the amplifier (on the control) furnishes current to Both the heating and cooling functions are performed by energize the compressor clutch coil.
Page 47 HEATER AND AIR C O N D ITIO N IN G 1 A -2 . enough, works quite a bit like a teakettle boiling on a speak of temperature from now on, we will mean stove. That may sound far-fetched, but there is more They can tell how hot a substance is, but Fahrenheit).
Page 48 A -24 HEATER AND AIR C O NDITIO NING The drain water was only a few degrees warmer than the Perhaps we can get a better idea of these two ice yet it didn’t draw nearly as much heat out of the characteristics of heat if we think of heat as a sort of stored foods.
Page 49 HEATER AND AIR C O N D ITIO N IN G 1A-25 water in the other glass to reach the same temperature. Obviously, most of the heat was being used to melt the ice. But it was the heat that apparently disappeared or was transformed because it couldn’t be located with a thermometer.
Page 50 1A-26 HEATER AND AIR C O N D ITIO N IN G But a boiling point below the temperature at which ice forms is not the only thing that makes a good refrigerant. A refrigerant should also be non-poisonous and non-explosive to be safe. Besides that, we want a refrigerant that is non-corrosive and one that will mix with oil.
Page 51 HEATER AND AIR C O N D ITIO N IN G 1A-27 to expand it and then letting the same amount of air out Pressure-Temperature Relationships of R-12 again to return the balloon to its original condition. A definite pressure and temperature relationship exists in We know that any substance will condense at the same the case of liquid refrigerants and their saturated vapors.
Page 52 1A-28 HEATER AND AIR C O N D ITIO N IN G would be doing would be to circulate the vapor without increasing its pressure. We can’t just block the flow through the system entirely. All we want to do is put pressure on the refrigerant vapor so it will condense at normal temperatures.
Page 53 HEATER AND AIR C O N D ITIO N IN G 1A-29 vapor, or relative humidity, affects the way we perspire BASIC AIR CONDITIONER on hot days. Nature has equipped our bodies with a network of sweat When we look at an air conditioning unit, we will always glands that carry perspiration to the skin surfaces.
Page 54 1A-30 HEATER AND AIR C O N D ITIO N IN G LIGHT DUTY TRUCK SERVICE MANUAL...
Page 55 HEATER AND AIR C O N D ITIO N IN G 1A-31 and held in place by a retainer ring. The entire pulley considerably cooler metal surfaces of the condenser. This is due to the fundamental laws, covered earlier, which and bearing assembly is then pressed over the front head state that "heat travels from the warmer to the cooler of the compressor and secured by a retainer ring.
Page 56 1A-32 HEATER AND AIR C O N D ITIO N IN G 33 34 35 37 38 Rear Head Pulley and Bearing Assembly Thrust Race Rear Head to Shell " O ” Ring Pulley Bearing Compressor Shell Rear Discharge Valve Plate Pulley Bearing Retainer Ring Cylinder Assembly Rear Suction Reed Plate...
Page 57 HEATER AN D AIR C O N D ITIO N IN G 1A-33 49 48 47 46 30 27 Drive Key Shaft N u t Discharge Crossover Shaft Seal Seat Clutch Hub Retainer Retainer Ring Discharge Crossover Tube Rear " O " Ring Ring Shaft Seal Seat Tube...
Page 58 1A-34 HEATER AND AIR C O N DITIO NING and the wobble plate at the tightest place throughout its end and four threaded studs welded to the outside of the 360° rotation (fig. 35). rear end. The oil sump is formed into the shell and a baffle plate is welded over the sump on the inside of the shell.
Page 59 HEATER AND AIR C O N D ITIO N IN G 1A-35 Fan Slip Clutch Compressor Connector A special engine fan is used on most systems. It is a 19.5 Compressor connectors, are attached to the compressor inch six or seven bladed fan, limited by means of a rear head by means of a single bolt and lock washer.
Page 60 1A -36 HEATER AND AIR CO N DITIO N IN G power element provides accurate control of the quantity of refrigerant to the cooling coil. To employ our tire pump analogy once more for clarity, it is the same situation that would exist if you were inflating a tire with a very slow leak.
Page 61 HEATER AND AIR C O N D ITIO N IN G 1A-37 hole is required to prevent trapping of oil in the bottom gets colder, the gas in the thermostatic tube begins to of the accumulator; this oil bleed hole bleeds some liquid reduce the pressure on the switch bellows.
Page 62 1A-38 HEATER AND AIR C O N D ITIO N IN G system cannot be easily removed, they build up into a Desiccant (Dehydrating Agent) constantly accelerating vicious circle to eventually fail the system. An ideal desiccant must have the following characteristics: 1.
Page 63 HEATER AND AIR C O N D ITIO N IN G 1A-39 strain on the discharge reeds also irt&reases. This can Due to the fact that sufficient oil then cannot be returned result in broken reeds. Due to the effect of the to the compressor, it may seize.
Page 64 1A -40 HEATER AND AIR CO NDITIO NING and the refrigerant, causes damaging corrosion. While SYSTEM CONTROLS the corrosion may not form as rapidly with R-12 as with some other refrigerants, the eventual formation is as Four-Season System (C-K Models) - Fig. 40 damaging.
Page 65 HEATER AND AIR C O N D ITIO N IN G 1A-41 speed of the blower motor. There are, however, the mode of operation: OFF, MAX, NORM, HEAT, limitations to the control of blower speed. To provide DEFOG or DEF. When the system selector lever is constant ventilation, the blower motor electrical circuitry placed in the A/C, positions, electrical circuit connection prevents the blower motor from being shut off when the...
Page 66 1A-42 HEATER AND AIR C O N D ITIO N IN G Dash Mounted Unit (M otor Home Chassis Units) This system is self contained and is mounted below the dash by the body manufacturer. System controls consist of an AIR knob and TEMP knob located in the center of the unit face plate (fig.
Page 67 HEATER AND AIR C O N D ITIO N IN G 1A-43 • Protection of the eyes is of vital importance! When use of improper wrenches may damage the working around a refrigerating system, an accident connection. The opposing fitting should always be may cause liquid refrigerant to hit the face.
Page 68 1A-44 HEATER AND AIR C O N D ITIO N IN G use. Thus a current air conditioning dealer can use the J-8393 CHARGING STATION equipment on hand and avoid duplication. The J-8393 Charging Station is a portable assembly of a vacuum pump, refrigerant supply, gauges, valves, and GAUGE SET most important, a five (5) pound metering refrigerant...
Page 69 HEATER AND AIR C O N D ITIO N IN G 1A-45 desire to flush out the pump, use this same type clean oil. Do not use solvent. Improper Lubrication will shorten pump life. • If this pump is subjected to extreme or prolonged cold, allow it to remain indoors until oil has reached approximate room temperature.
Page 70 1A-46 HEATER AND AIR C O ND ITIO NING immediately (before system pressures equal ize). A leak on the low pressure side may be CHIMNEY more easily detected after the engine has REACTION PLATE been shut off for several minutes (system pressures equalized);...
Page 71 HEATER AND AIR C O N D ITIO N IN G 1A-47 number consists of a series of numbers and letters. This serial number should be referenced on all forms and correspondence related to the servicing of this assembly. INSPECTION AN D PERIODIC SERVICE 2.
Page 72 1A-48 HEATER AND AIR C O N D ITIO N IN G 5. Connect the high pressure gauge line to the high vacuum pump and put the line in a covered can as pressure fitting on the system. shown in Figure 50. 6.
Page 73 HEATER AND AIR C O N D ITIO N IN G 1A-49 1. Install charging station and purge system as by an amount equal to that lost during discharge previously described. of system plus 1/2 ounce, then close valve. Take 2.
Page 74 1A-50 HEATER AND AIR C O N D ITIO N IN G PERFORMANCE TEST -24095 Under normal circumstances, it will not be necessary to Performance Test a system as outlined below; however, TO L O W in certain instances, the following procedure may be PRESSURE FITTING advantageous in diagnosing system malfunction.
Page 75 HEATER AND AIR C O N D ITIO N IN G 1A-51 Overhead System (G Models) (Refrigerant Charge — 5 lbs.-4 oz.) Four-Season A ir Conditioning (C-K Models) Temperature of (Refrigerant Charge - 3 Lbs. Air Entering 100° 110° 120° -1 2 o z .) Condenser Temperature of...
Page 76 1A-52 HEATER AND AIR CO N D ITIO N IN G a. Remove the compressor, drain, measure and To further check the compressor oil charge, should the discard the oil. above test show insufficient oil, it is necessary to remove the compressor from the vehicle, drain and measure the b.
Page 77 HEATER AND AIR C O N D ITIO N IN G 1A-53 REFRIGERANT QUICK-CHECK PROCEDURE The following procedure can be used to quickly determine whether or not an air conditioning system has a proper charge of refrigerant. This check can be made in a manner of minutes thus facilitating system diagnosis by pinpointing the problem to the amount of charge in the system or by eliminating this possibility from the overall checkout.
Page 78 1A-54 HEATER AND AIR C O ND ITIO N IN G Fig. 5 2 -Checking Evaporator Inlet and Accumulator Outlet Temperatures MAINTENANCE AND ADJUSTMENTS 2. Set the control at A/C, HI blower, max COLD and THERMOSTATIC SWITCH run the engine at 2000 rpm. C-K Systems and Motor Home Chassis Units make use •...
Page 79 HEATER AND AIR C O N D ITIO N IN G 1A-55 3. Remove the switch as outlined in the "Component 2. Remove the control to instrument panel screws. Part Replacement" section of this manual. 3. Remove the left foot cooler bracket to instrument 4.
Page 80 1A 56 HEATER AND AIR C O N D ITIO N IN G Very Low Suction Pressure. No Cooling. POORLY LOCATED POWER ELEMENT BULB Normal Pressure. Poor Cooling. Check for Defective Valve The following procedure must be followed to determine if a malfunction is due to a defective expansion valve.
Page 81 HEATER AND AIR C O N D ITIO N IN G 1A-57 must be removed before restoring the system to Removal operation. 1. Carefully, with a sharp knife, make an angle cut in In the case of compressor mechanical failure, perform the hose as shown in Figure 56.
Page 82 1A-58 HEATER AND AIR C O N D ITIO N IN G sure that all of the failed portion is removed. If REPAIR OF REFRIGERANT LEAKS only a very small portion of the hose was removed, Any refrigerant leaks found in the system should be it may be possible to splice the two ends together repaired in the manner given below: using a special hose connector and two hose clamps.
Page 83 HEATER AND AIR C O N D ITIO N IN G 1A-59 3 0 7 - 3 5 0 V -8 C-K MODELS 3 5 0 V -8 MODELS A N D MOTOR HOME CHASSIS 4 5 4 V -8 C-K MODELS 4 5 4 V -8 M OTOR HOME CHASSIS Fig.
Page 84 1A-60 HEATER AND AIR C O N D ITIO N IN G 7. Remove fitting and muffler assembly and cap or COMPRESSOR FAILURE plug all open connections. If the compressor has failed mechanically to the extent 8. Remove the nuts and bolts attaching the compres that metal chips and shavings are found in it, the system sor to the bracket.
Page 85 HEATER AND AIR C O N D ITIO N IN G 1A-61 1. Remove the drive belt. 3. Install Charging Station. 2. Visually inspect the condenser, accumulator, 4. Purge the system. receiver-dehydrator, compressor, mounting brack 5. Remove the compressor from mounting and ets, conditioning unit, all connecting lines, and all remove the oil test fitting.
Page 86 1A-62 HEATER AND AIR C O N D ITIO N IN G Fig. 58- Condenser Installation (C-K Models) 7. To install the new accumulator, reverse Steps 1-4 ACCUMULATOR above. Connect all lines using new "O" rings, Replacement (Fig. 59) coated with clean refrigeration oil. 1.
Page 87 HEATER AND AIR C O N D ITIO N IN G 1A-63 Fig. 6 0 -Blower-Evaporator (C-K Models) Fig. 6 1 -Expansion Tube (C-K Four-Season System) 3. Remove the nuts from the selector duct studs 4. Remove the expansion tube "O" ring from the core projecting through the dash panel.
Page 88 1A-64 HEATER AND AIR C O N D ITIO N IN G Fig. 63-Air Selector and Ducts (C-K Models) 12. Refill coolant system and connect the battery 3. Remove the glove box and door as an assembly. ground strap. Check temperature door cable 4.
Page 89 HEATER AND AIR C O N D ITIO N IN G 1A-65 7. If a new unit is being installed, transfer the master and blower switches to the new control. 8. To reinstall, reverse Steps 1-6 above. Check control operation. TEMPERATURE DOOR CABLE ADJUSTMENT 1.
Page 90 1A-66 HEATER AND AIR C O N D ITIO N IN G 2. Remove the resistor to case attaching screws and remove the resistor. 3. Place the new resistor in position and install the attaching screws. 4. Connect the resistor wiring harness. BLOWER MOTOR RELAY The blower motor relay is located on the blower side of the blower-evaporator case (fig.
Page 91 HEATER AND AIR C O N D ITIO N IN G 1A-67 to evaporator line (fig. 69). Replacement 1. Disconnect the battery ground cable. 2. Purge the system of refrigerant. 3. Disconnect the wiring harness at the switch. 4. Remove the switch from the refrigerant line. 5.
Page 92 1A-68 HEATER AND AIR C O N D ITIO N IN G COMPONENT PART REPLACEMENT OVERHEAD SYSTEM--C-K MODELS The Overhead System is used in conjunction with the BLOWER MOTOR RESISTOR Four-Season System. Since replacement of Four-Season System components has been covered previously, only The blower motor resistor is located on the cover side of those components peculiar to the Overhead System will the Four-Season System blower-evaporator as shown in...
Page 93 HEATER AND AIR C O N D ITIO N IN G 1A-69 Fig. 72-Overhead System Front Wiring (C-K Models) 2. Disconnect the electrical harness at the resistor. 2. Remove the rear duct as outlined previously. 3. Remove the resistor attaching screws and remove 3.
Page 94 1A-70 HEATER AND AIR C O N D ITIO N IN G EVAPORATOR BLOWER-EVAPORATOR SCREEN UPPER CASE EXPANSION EVAPORATOR VALVE CORE SENSING BULB Fig. 7 5 -Expansion Valve (C-K Overhead System) 2. Install the sensing bulb, making sure that the bulb makes good contact with the core outlet line.
Page 95 HEATER AND AIR C O N D ITIO N IN G 1A-71 6. Connect the refrigerant lines to the blower- evaporator unit using new "O" rings coated with clean refrigeration oil. 7. Connect the blower lead and ground wires. 8. Install the rear duct as outlined previously. 9.
Page 96 1A-72 HEATER AND AIR C O N D ITIO N IN G 2. Remove screws securing the blower-evaporator clean refrigeration oil, when connecting all shield; remove the shield. Remove the shield refrigerant lines. bracket to instrument panel reinforcement screws and remove the bracket. 10.
Page 97 HEATER AND AIR C O N D ITIO N IN G 1A-73 Fig. 78-Sight Glass Replacement door pillar and forward engine housing screws and lower the blower-evaporator assembly. Disconnect lower the blower-evaporator assembly. Disconnect electrical connections, pull evaporator drain hose electrical connections, pull evaporator drain hose through the dash panel and then remove the through the dash panel, and remove the blower-...
Page 98 1A-74 HEATER AND AIR C O N D ITIO N IN G RH DASH OUTLET A / C DISTRIBUTION BLOW ER-EVAPO RATO R ASSEMBLY DUCT CENTER OUTLETS INSTRUMENT PANEL REINFORCEMENT— RH LH DASH OUTLET HEATER INTERMEDIATE D U C T-R H SIDE INSTRUMENT PANEL SHIELD REINFORCEMENT—...
Page 99 HEATER AND AIR C O N D ITIO N IN G 1A-75 and disconnect the line from the evaporator core. Disconnect the expansion valve inlet and outlet lines and remove the expansion valve. Cap or plug all open connections at once. 6.
Page 100 1A-76 HEATER AND AIR C O N D ITIO N ING connections, use new "O" rings coated with clean refrigeration oil. TEMPERATURE DOOR CABLE Replacement 1. Purge the system of refrigerant. 2. Follow Steps 1-8 of "A/C Air Distributor Duct- Replacement".
Page 101 HEATER AND AIR C O N D ITIO N IN G 1A-77 Fig. 85-Discharge Pressure Switch (G Models) Fig. 83- Resistors (G Model C60 System) 2. Disconnect electrical harness at the relay. conditioning). The A/C blower motor resistor is mounted 3.
Page 102 1A-78 HEATER AND AIR C O N D ITIO N IN G VACUUM TANK Replacement (Fig. 86) 1. Raise the hood. 2. Disconnect the vacuum harness at the tank. 3. Remove the tank attaching screws and remove the tank. 4. To install, reverse Steps 1-3 above. CIRCUIT BREAKER The entire air conditioning system is protected by a 35 amp circuit breaker located on the left side of the dash,...
Page 103 HEATER AND AIR C O N D ITIO N IN G 1A-79 Before removing the case screws, WARNING: Removal (Inner Valve) support the lower case to prevent damage to 1. Disconnect the battery ground cable and compres the case or motor assemblies. sor clutch connector.
Page 104 1A-80 HEATER AND AIR CO NDITIO NING 8. Remove the expansion valve bulb from the 4. Disconnect the blower motor leads and ground evaporator outlet line. Remove the expansion valve wire. inlet and outlet lines and cap or plug the open 5.
Page 105 HEATER AND AIR C O N D ITIO N IN G 1A-81 BLOWER SWITCH 2. Remove screws securing the blower-evaporator Replacement (Fig. 92) shield; remove the shield. Remove the shield 1. Disconnect the battery ground cable. bracket to instrument panel reinforcement screws and remove the bracket.
Page 106 1A-82 HEATER AND AIR C O N D ITIO N IN G Fig. 94 -Condenser (Motor Home Chassis Unit) Unit) 4. Remove the condenser to radiator support screws and remove the condenser. SIGHT GLASS REPLACEMENT 5. To install a new condenser, reverse Steps 1-4 above. Refer to "Sight Glass Replacement"...
Page 107 HEATER AND AIR C O N D ITIO N IN G 1A-83 4. Disconnect drain tubes from evaporator case. lower case halves. Remove blower motor mounting strap screw and remove strap. 5. Disconnect electrical connector from compressor. Remove the terminal (See Figure 97) and allow 2.
Page 108 1A-84 HEATER AND AIR C O N DITIO NING evaporator case. 2. Remove two screws securing either switch to the cover plate and remove appropriate switch (fig. THERMOSTATIC SWITCH AIR SENSING CAPILLARY 3. Install replacement switch, reinstall cover plate and reverse steps 1-8 of the "Blower-Evaporator Assembly"...
Page 109 HEATER AND AIR C O N D ITIO N IN G 1A-85 Expansion Valve Refrigerant Line Restrictions A malfunction of the expansion valve will be caused by Restrictions in the refrigerant lines will be indicated as one of the following conditions: valve stuck open, valve follows: stuck closed, broken power element, a restricted screen or 1.
Page 110 -86 HEATER AND AIR C O ND ITIO N IN G Vacuum Less Than Normal At All Positions - Specific Vacuum Circuit Check Remove the tee and connect the vacuum gauge Place the selector lever in the malfunctioning line directly to the tank - read the vacuum. If position and check for vacuum at the pertinent still low, then the problem lies in the feed circuit, vacuum actuators.
Page 111: Compressor Diagnosis
COMPRESSOR DIAGNOSIS Retrace electrical circuit back to source of power loss. (See wiring diagrams). C-K-G MODELS: NO VOLTAG E AT Check fo r defective discharge Pressure Switch by jumping switch connector terminals. If compressor COMPRESSOR COIL. operates, check fo r low refrigerant charge. If charge is satisfactory, switch is defective-replace.
Page 112 IN SU F F IC E N T C O O L IN G - F O U R S E A S O N S Y S T E M (C - K M O D E L S ) M ove temperature lever rapidly back and forth from max.
Page 113 I N S U F F I C I E N T C O O L IN G D I A G N O S I S C H A R T (EXCEPT C - K F O U R - S E A S O N S Y S T E M ) The following procedures should be applied before performance testing an A/C System.
Page 114 ELECTRICAL SYSTEM DIAGNOSTIC CHART BLOW ER M OTOR IN O P E R A T IV E BLOWER MOTOR INOP ER ATIV E (C E R T A IN SPEEDS-EXCEPT HIGH ( A N Y SPEED) ON C-K FO U R -S EAS O N ) Check fo r proper fuse 1 FUSE B L O W N ]...
Page 115 E L E C T R IC A L S Y S T E M D I A G N O S T I C C HAR T BLOWER MOTOR IN O PE R A TIV E COMPRESSOR CLUTCH IN O P E R A T IV E A T HIGH SPEEO O N LY I^Check^fuse^ (C-K FOUR-SEASON SYSTEM)
Page 116 BLOW ER R E LA Y JUNCTION COMPRESSOR RESISTOR I - ------1 t/VWWW| DISCHARGE THERM O BLOCK D C l BLOW ER MOTOR r PRESSURE STATIC 15911501 CUT-OUT SWITCH r a r RES. BAT. SWITCH -10 RED- C k J BLO.
Page 117 TO VACUUM SOURCE g r a y VACUUM PLENUM TANK DASH VALVE PANEL (O.A.) ORANGE p i n k z i GROMMET t a n A /C MODE HEATER MODE GRAY KICK PAD VALVE (| A ) jy DEFROSTER CONTROL GRAY 1 0 9 «...
Page 118 IGN UNFUSED ■ ....10 ORN 120 AMP INLINE FUSE ---------------------------------- 16 YEL' 14 ORN at O RESISTOR FUSE PANEL r l i . 5 2 1 5 0 I □ ■ ' s rTAED I O " i m r a j 10 PPL' CIRCUIT BATT TO NONE...
Page 119 A /C BLOW ER R E LA Y A /C BLOW ER HEATER BLOW ER DISCHARGE RESISTOR R ESISTOR PRESSURE CUT OUT tvW - a a a a a COMPRESSOR rvW'- SWITCH A /C L •AAt H50I59BI M 21 Q f- 1 R E L •s^CQ LO M2...
Page 120 VACUUM R E S E R V O IR (IN ENG INE CO M PA RT M EN T ) TO VACUUM SORCE g r a y DASH P A N E L H E A T E R C O R E CASE g r a y = p i n k : ____...
Page 121 DISCHARGE A /C B L O W E R R E L A Y A /C B L O W E R R E L A Y A /C B L O W E R RE SIST O R H E A T E R B LO W E R - (C69) PRESSURE (C60)
Page 122 THERMOSTATIC SWITCH Fig. 112-Motor Home Chassis Wiring Diagram...
Page 123: Special Tools
HEATER AND AIR C O N D ITIO N IN G 1A-99 SPECIAL TOOLS Charging Station J-8393 J-5403 No. 21 Snap Ring Pliers J-9481 Pulley and Bearing J-24095 Oil Inducer Installer J-6435 No. 26 Snap Ring Pliers J-9396 Compressor Holding J-8092 Handle J-5453...
Page 125 SECTION IB BODY The following caution applies to one or more steps in the assembly procedure of components in this portion of the manual as indicated at appropriate locations by the terminology "See Caution on page 1 of this Section". THIS FASTENER IS AN IMPORTANT ATTACHING CAUTION: PART IN THAT IT COULD AFFECT THE PERFORMANCE OF...
Page 126 1 B-2 BODY Crew Cab/Chassis Model number "63" designates the crew cab/chassis models. See figure 2. Optional pickup boxes are available. Coach The four-door coach model number is "06". See figure 3. Base models have rear cargo doors. An optional endgate with moveable window is available.
Page 127 B O D Y I B - 3 Fig. 5— Typical "0 5 " and "0 6 " Vans LIGHT DUTY TRUCK SERVICE MANUAL...
Page 128 1 B-4 BODY C-K MODELS INDEX Replacement.............IB-14 Front End Windshield Wipers........... IB-4 Hinges...............IB-14 Stationary G lass.............IB-14 Glove Box..............IB-5 Window and Regulator........IB-15 Rear View Mirrors........... IB-5 Locks, Handles, Rods..........IB-15 Body Glass Windshield Glass............IB-6 Weatherstrip............IB-16 Stationary Body Glass..........IB-9 Rear Doors Adjustments..............IB-16 Side Doors Locks, Handles, Rods..........IB-17...
Page 129 BODY 1B-5 Fig. 8— Glove Box INSTRUMENT PANEL COMPARTMENT AND LOCK Replacement Removal of the entire assembly including door may be accomplished by removing four screws which attach hinge just below box. See figure 8. The outer door panel may be removed, leaving the compartment intact, by removal of four screws.
Page 130 1 B-6 BODY COWL VENT VALVE— FIGURE 12 Replacement The entire vent valve assembly may be removed from the vehicle by removing attaching screws shown in figure Fig. 12— Cowl Vent Valve BODY GLASS important that the cause of the glass breakage be Always wear gloves when han...
Page 131 BODY 1B-7 Fig. 14— Applying Pressure to Windshield Fig. 15— Assisting Weatherstrip over Flange 5. With the aid of an assistant outside the cab, remove the windshield from the opening. See figure 16. Checking Windshield Opening Due to the expanse and contour of the windshield it is imperative in the event of a stress crack that the windshield opening be thoroughly checked before installing a replacement windshield.
Page 132 1 B-8 BODY Installation 1. Place a protective covering over front fenders and hood, then apply soapy water to all grooves of the weatherstrip. 2. Install weatherstrip centrally to the body opening, with the pinchweld flange in the inner weatherstrip groove.
Page 133 BODY 1B-9 STATIONARY BODY GLASS Replacement The method used to remove the windshield glass may be applied to other stationary glass, such as shown in figures 20 and 21. Remember to check for cause of breakage, and to always wear gloves when handling glass. Installation procedures are similar to G-Van windshield.
Page 134 1B-10 BODY assure that the right proportion of door’s DOOR HINGE weight will rest on striker bolt when door is The door check is part of the front door upper hinge. closed. If bolt is positioned too high on pillar, The front door torque rod check holds the door in either rapid wear will occur to the lock cam;...
Page 135 BODY 1B-11 channel or frame to soften the old seal. When the seal has softened, remove the glass from the channel. 2. Thoroughly clean the inside of the glass channel with sandpaper, removing all rust, etc. 3. Using new glass channel filler, cut the piece to be installed two inches longer than necessary for the channel.
Page 136 1B-12 BODY TO ADJUST TENSION, TURN THE VENT WHILE HOLDING A WRENCH ON THE HEX NUT Fig. 30— Door Window and Regulator Fig. 28— Adjusting Tension 2. Remove window regulator handles using tool WINDOW REGULATOR— FIG. 30 J-7797, and remove remote control push button Replacement knob.
Page 137 BODY IB -1 3 Door Lock Assembly Replacement 1. Raise window to gain access to lock. 2. Remove regulator handle. 3. Remove remote control push button knob. 4. Remove trim panel. 5. Remove clip from inside handle rod-to-lock. 6. Remove clip from outside handle rod-to-lock. This is best accomplished by inserting a long screwdriver through the daylight opening, as shown in figure 32.
Page 138 1B-14 BODY DOOR TO BODY OPENING WEATHERSTRIP— FIGS. 35, 36 Side door sealing incorporates an inner seal. The inner seal is mounted on the body opening welding flange and goes completely around the periphery of the opening. The molded weatherstrip material is snapped in place. Success of weatherstrip replacement depends entirely upon the quality of the cement used and the care with which it is applied.
Page 139 BODY IB -1 5 Fig. 38— Side Rear Door Trim Pad Fig. 40— Window Glass and Regulator Assembly 4. Install regulator by reversing above procedure. channel. See figure 40. Disengage roller from channel. Lubricate regulator gear with lubriplate or equivalent. 5.
Page 140 1B-16 BODY Fig. 41— Lock Assembly and Inside Handle Fig. 43— Outside Handle Remote Control— Fig. 42 Replacement 1. Remove regulator handle, remote control knob and 3. Remove two screws securing outside handle to door panel. trim pad. 2. Disconnect remote control lower rod from door lock 4.
Page 141 BODY IB -1 7 Fig. 45— Rear Door Controls REAR DOORS (06 ONLY) Adjustments Rear doors may be adjusted in the body opening by loosening hinge bolts and repositioning door, then retightening bolts. See figure 47 for hinge bolt location. Rear door wedges and strikers should be adjusted as shown in figure 48.
Page 142 1B-18 BODY 2. Remove check arm access cover. 3. With one hand supporting housing assembly and insulator on the inside of the door panel, remove bolts securing housing assembly to door. 4. Remove housing, insulator and check arm. 5. To separate check arm from bracket, remove holding pin connecting the two parts.
Page 143 BODY 1B-19 (06 AND 14) ENDGATES Coach models (06) and utility models (14) use endgates of similar, yet distinct design. Separate procedures follow for service on each of these endgates. ENDGATE ASSEMBLY- (06) MODELS ONLY Replacement 1. Lower endgate, and remove hinge access covers. See figure 50.
Page 144 I B -20 BODY Fig. 53— Window Glass and Regulator— (06 Only) Fig. 54— Outside Handle (06 and 14) 8. Unclip and remove inner and outer seal assemblies. ENDGATE ASSEMBLY- 9. Remove screws connecting window regulator assembly to endgate, figure 53, and remove (14) MODELS ONLY regulator.
Page 145 BODY 1B-21 disconnect support cables from endgate. See figure 4. Remove endgate by pulling disconnected hinge from body, figure 56, then grasping torque rod with one hand and pulling torque rod over gravel deflector, as shown in figure 57. 5. Individual components may be removed from the endgate now, or after reinstallation.
Page 146 1B-22 BODY 5. Refer to figure 63 for installation of latch control 5. Remove torque rod retaining bracket on lower edge and blockout rod. of endgate. See figure 59. 6. Remove torque rod retaining clip on side edge of 6. Disconnect blockout rod from control assembly by endgate.
Page 147 BODY 1B-23 Fig. 66— Disconnecting Sash from Regulator Fig. 64— Removing Control Assembly and Inside Handle 13. Remove glass from endgate. 14. Remove four regulator attaching screws and withdraw regulator from endgate as shown in figure 15. Remove outside handle by removing nuts from inside of outer panel.
Page 148 1B-24 BODY screws attaching both trunnions to body, and lifting the 4. Lower the door windows. tailgate off the vehicle. 5. Slide top rearward approximately 18" to expose the bottom rear top-to-pickup box attaching holes. The tailgate shown in figure 70 can be separated from the vehicle by removing the bolt and lock washer from 6.
Page 149 BODY 1B-25 cleaning. Vacuum area to remove excess loose dirt. SEATS Always clean at least a full trim panel or section of trim. Care and Cleaning Mask adjacent trim along stitch or weld lines. Mix of Interior Soft Trim detergent type foam cleaners in strict accordance with Dust and loose dirt that accumulate on interior fabric directions on label of container.
Page 150 1B-26 BODY SEAT MOUNTING Typical Seat Mounting provisions are shown in figures 73 through 81. CAUTION: See CAUTION on page 1 of this section regarding fasteners used on seats and seat belts. Fig. 75— Passenger’s Bucket Seat (03) Fig. 73— Front Bench Seat (03, 06 and 63) Fig.
Page 151 BODY 1B-27 Fig. 78— Rear Bench Seat (63) Fig. 79— Rear Bench Seat (06) Fig. 81— Rear Bench Seat (14) LIGHT DUTY TRUCK SERVICE MANUAL...
Page 152 1B 28 BODY BODY MOUNTING The sequence of mounting attachments is shown in figures 82 through 85. Fig. 83— Body Mounting (63) LIGHT DUTY TRUCK SERVICE MANUAL...
Page 153 BODY 1B-29 Fig. 85— Body Mounting (14) LIGHT DUTY TRUCK SERVICE MANUAL...
Page 154 1B-30 BODY G MODELS INDEX Front End Sliding Side Door Windshield Wipers.............IB-30 Adjustments..............IB-38 Cowl Ventilator G rille..........IB-31 Front Latch..............IB-41 Side Ventilator Valve..........IB-31 Rear Latch..............IB-42 Rear View M irror............IB-32 Upper Left Hinge............IB-42 Body Glass Windshield Glass............IB-32 Rear Door Hinge................IB-44 Stationary Glass............IB-34 Remote Control............IB-44 Swingout Glass............IB-34...
Page 155 BODY 1B-31 Fig. 2G— Windshield Wiper Linkage Fig. 4G— Side Cowl Ventilator 3. Install outside air cowl ventilator grille to top of COWL SIDE VENT VALVE cowl. Replacement 4. Before installing wiper arms, operate wiper motor 1. Remove screws retaining valve guide to panel, as momentarily which should rotate pivot shafts to shown in figure 4G.
Page 156 1B-32 BODY REAR VIEW MIRRORS Inside Rear View Mirror Replacement The inside mirror may be removed by removing screw retaining mirror to its glass-mounted bracket, and lifting mirror off bracket. Outside Rear View Mirrors Outside rear view mirror installations are shown in figure 6G.
Page 157 BODY 1B-33 3. Check flange area for solder, weld high spots, or hardened spot-weld sealer. Remove all high spots. 4. Check windshield glass to opening, by supporting glass with six spacers contained in packet J-22577, as shown in figure 8G. CAUTION: Do not strike glass against body metal.
Page 158 1B-34 BODY d. Seal windshield to weatherstrip and weatherstrip to body. SWINGOUT WINDOW Removal 1. Swing out the window. See figure 11G. 2. Remove screws retaining latch to body. 3. Remove window hinge retaining screws and window. 4. Remove latch from glass. Installation 1.
Page 159 BODY IB -3 5 possible. Alignment adjustments can be made by loosening the proper hinge bolts, aligning door to proper position, and tightening bolts securely. See figure 12G, for typical adjustments. Striker Bolt Adjustment J-23457 With the use of J-23457, shown in figure 13G, the striker bolt can be adjusted in any of three ways.
Page 160 1B-36 BODY 1. Open door and block open. 2. Remove side door weatherstrip. 3. Remove used adhesive from door with adhesive or cement remover, and remove all plastic nails. 4. Apply adhesive to door. 5. Position weatherstrip by locating part number at top of vent window, making sure that plastic nails align with holes in door.
Page 161 BODY 1B-37 2. Make certain the rubber lip is positioned before tightening screws. 3. Slide door glass forward engaging glass in vent channel. 4. Reinstall all screws and tighten. 5. Install and tighten the three screws at the upper front of the door. Adjustment 1.
Page 162 1B-38 BODY Fig. 19G— Lock and Remote Control Assembly NOTE: Connecting rod can be removed at 5. Check all controls for proper operation before this point by disconnecting spring clip from reinstalling trim and handles. lock. 6. Install remote control sill knob. 4.
Page 163 BODY 1B-39 STRIKER FORE-AND-AFT ADJUSTMENT SLOTS CENTER ROLLER VERTICALLY IN TRACK SO IT DOES NOT CONTACT THE TRACK / f = = = = ^ IN FULL OPEN U P-AN D-DOW N OR FULL 1 1 1 . . . | . . Jj ADJUSTMENT SLOTS CLOSED POSITION...
Page 164 1B-40 BODY 2. Loosen rear wedge assembly. 3. Remove upper rear track cover. 4. Loosen upper rear hinge striker. 5. Move door assembly forward or rearward, then tighten striker bolts to specifications. 6. Reinstall upper rear track cover. 7. Reinstall front and rear latch strikers. 8.
Page 165 BODY 1B-41 Fig. 23G— Hold-Open Catch 2. The lower lever must extend at least .10 inch COMPONENT PARTS outboard of the striker tang. Add or delete shims REPLACEMENT between the striker and the body as necessary. 3. If necessary to shim roller away from guide, shims FRONT LATCH ASSEMBLY are added between the nylon block and hinge and Removal...
Page 166 1B-42 BODY LOCKING ROD REAR LATCH RODS LOWER HINGE LOCK CYLINDER DOOR CATCH Fig. 25G— Sliding Door Front Latch 3. Install access covers and trim panels (if so REAR LATCH AND/OR LATCH ACTUATING equipped). RODS 4. Adjust rear latch striker as outlined earlier under Removal "Adjustments".
Page 167 BODY 1B-43 Fig. 28G— Rear Track Cover Fig. 30G— Checking Assembly of Hinge Roller Bolt 15. Screw 2 1 . Lockwashers 9. Plate Guide Block Bushing Upper Lever Hinge (Body Half) Hinge (Door Half) 11. Spacer Spring Washer 12. Spring (Upper Lever) Bushing Spring retainer Bushing...
Page 168 1B-44 BODY REAR DOORS REAR DOOR HINGE STRAP REAR DOOR REMOTE CONTROL Replacement Removal 1. Remove strap release pin. See figure 31G. 1. Remove trim panel. 2. Remove screws retaining strap to door. 2. Disengage upper and lower latch rods from control by removing retaining clips.
Page 169 BODY IB -4 5 NOTE: When reinstalling the lower latch rod REAR DOOR GLASS AND WEATHERSTRIP to control, the short straight section attaches Removal and installation procedures are the same as for to the latch. the stationary body side windows. Refer to those procedures for rear door glass and weatherstrip 2.
Page 170 1B-46 BODY SEATS See CAUTION on page 1 of this PASSENGER SEAT-MOUNTING BRACKETS CAUTION: section regarding fasteners used on seats and Removal seat belts. 1. Remove seat and brackets from seat riser. See figure 36G. DRIVERS SEAT 2. Remove brackets from seat. Seat Adjuster Installation Replacement...
Page 171 BODY 1B-47 NOTE: After removing the rear seat, reinstall Shoulder of Bolt must bottom on CAUTION: the bolts into the anchor nuts to seal the weld nut. openings from dirt and foreign matter. 3. Attach seat to floor. Torque bolts to specifications. 3.
Page 172 IB -4 8 BODY SPECIAL TOOLS Weatherstrip Tool Set 1. J-2189 Front Door Hinge, Bolt Wrench 2. J-22585 3. J-22577 Windshield Checking Blocks Door Handle Clip Remover 4. J-7797 5. J-23457 Door Striker Bolt Remover and Installer Fig. I T — Special Tools LIGHT DUTY TRUCK SERVICE MANUAL...
Page 173 FRAME SECTION 2 FRAME INDEX Description 10-30 Series Truck .2-1 Frame Repair..............2-2 Maintenance........ .2-1 Welding................2-2 Frame Alignment.....2-1 Bolting................2-2 Horizontal Check....2-2 Underbody Alignment..........2-2 Vertical Check......DESCRIPTION Light duty 10-30 Series frames are of the ladder channel The G-Van frame side rails, cross sills and outriggers are section riveted type.
Page 174 2-2 FRAME drilled at the starting point of the crack to prevent 2. Dimensions must be within 3/16". spreading. Widen V groove crack to allow complete weld 3. If a tram bar is used, for horizontal alignment "X" penetration. - check from opposite and alternate reference points AA, BB and CC, as illustrated by the lines in NOTE: Do not weld into corners of frame or Figure 2.
Page 175 Fig. 2-Frame Horizontal Checking - Typical...
Page 176 2-4 FRAME n __-**— “— < O a -------------- J - T T 7 7 T & m ------------------------ r — ---------------- i t r ^ '— i---- --------- L i .._ i l — -L-l oTTl ® 9) ..\ r ~ ...
Page 177 Fig. 4--10-30 Series Truck Frame...
Page 178 2-6 FRAME LIGHT DUTY TRUCK SERVICE MANUAL...
Page 179 FRONT SUSPENSION SECTION 3 FRONT SUSPENSION The following caution applies to one or more steps in the assembly procedure of components in this portion of the manual as indicated at appropriate locations by the terminology “See Caution on page 1 of this Section”.
Page 180 3-2 FRONT SUSPENSION Front Suspension..............3-27 Steering Knuckle/Steering Arm........3-25 Ball Joint................3-30 Removal................3-26 Shock Absorber..............3-31 Installation..............3-26 Crossmember and Suspension Unit........3-26 On Vehicle..............3-31 Removal................3-26 Bench................3-32 Installation..............3-26 Bearings and Races............3-33 Diagnosis................3-27 Special Tools...............3-37 GENERAL DESCRIPTION upper control arms are attached to a frame bracket. The GM 10-30 series Truck line except K Series These control arms are connected to the steering knuckle incorporates an independent coil spring front suspension...
Page 181 G-10-20 G_30 P-10-30 Fig. 2— F ro n t Suspension C-P-K Typical...
Page 182 3-4 FRONT SUSPENSION Fig. 3— Wheel Hubs and Bearings THEORY OF OPERATION The front suspension can be divided into two types, the The steering knuckle and wheel spindle attach to the axle CONVENTIONAL, such as used on General Motors K Series ends through ball joints.
Page 183 FRONT SUSPENSION rigid axle and one of them passes over a bump the axle bolted to the steering knuckle. This arrangement allows executes an angular movement in the (front view) the front wheel suspension to move up and down with vertical plane and both of the wheels perform respect to the vehicle frame (spring action) and swing at movements of the same angular magnitude.
Page 184 3-6 FRONT SUSPENSION body while at the same time controlling wheel and axle motions. The vehicle’s springs support the body, but shock absorbers work with the springs to control movements of the body, wheel, and axle for smooth driving. This is accomplished by changing the movements of the spring (kinetic energy) into heat energy.
Page 185 FRONT SUSPENSION This cell, in the reservoir, acts the same as an air chamber, expanding and contracting to compensate for the volume of the piston rod. But since it is a gas filled cell, there is no free air to mix with the fluid; thus, aeration is eliminated.
Page 186 3-8 FRONT SUSPENSION EXTENSION FORCE INTAKE VALVE SPRING COMPRESSION HIGH SPEED VALVE ASSY. ORIFICE VALVE CAGE VALVE STEM BLOW OFF SPRING VALVE COMPRESSION RETAINER WASHER LOW SPEED ORIFICE CYLINDER END Fig. 11— Shock Absorber Rebound Cut Off Schematic Fig. 12— Compression Valve Parts shock absorber piston velocity.
Page 187 FRONT SUSPENSION Fig. 13— Piston Valving Parts WHEEL ALIGNMENT FRONT SUSPENSION GEOMETRY forward or backward from the vertical (when reviewed (FIG. 14) from the side of the vehicle). A backward tilt is said to The term “front suspension geometry” refers to the be positive( + ) and a forward tilt is said to be negative angular relationships between the front wheels, the front (—).
Page 188 3-10 FRONT SUSPENSION the same for both arms. Toe-out on turns is not CAMBER adjustable. Camber is the tilting of the front wheels from the vertical when viewed from the front of the vehicle. STEERING AXIS INCLINATION (S.A.I.) FIG. 16 When the wheels tilt outward at the top, the camber is Steering axis inclination (formally called kingpin said to be positive ( + ).
Page 189 FRONT SUSPENSION 3-11 CAMBER ANGLE CASTER ANGLE FRONT VIEW SIDE VIEW Fig. 14— Caster - Camber • Toe-in Fig. 15— Toe-out on Turns LIGHT DUTY TRUCK SERVICE MANUAL...
Page 190 3-12 FRONT SUSPENSION 0° CENTER LINE STEERING AXIS OF TIRE INCLINATION (♦- ______POSITIVE "T"—» CAMBER TRUE VERTICAL LEFT HAND FRONT VIEW Fig. 16— Steering Axis Inclination MAINTENANCE AND ADJUSTMENTS CAUTION: See CAUTION on page 1 of this 2. Spin wheel to check for unusual noise or roughness. section regarding the fasteners referred to in 3.
Page 191 “ UP IN REAR” ADDED to a caster reading. applicable), or whenever for other reasons the alignment POSITIVE is being reset, Chevrolet recommends that the specifica c. A ” frame angle must be “ DOWN IN REAR LIGHT DUTY TRUCK SERVICE MANUAL...
Page 192 3-14 FRONT SUSPENSION Toe-In <{. OF WHEEL <t O F WHEEL 1. Determine the wheel toe-in from the alignment equipment. 2. Change the length of both tie rod sleeves to affect a toe change. See Section 9 for proper tie rod positioning and orientation, torque tie rod clamps to specifications.
Page 193 FRONT SUSPENSION 3-15 CR OS S ME MBE R Fig. 19— Determining Caster - Typical (C Series Shown) LIGHT DUTY TRUCK SERVICE MANUAL...
Page 194 3-16 FRONT SUSPENSION PIVOT SHAFT OUTBOARD OF FRAME CASTER CAMBER ADD SHIMS HERE TO INCREASE CASTER FRAME FORWARD VSUBTRACT SHIMS HERE TO INCREASE CASTER Fig. 20— Caster - Camber Adjustment Fig. 21— Toe-in Adjustment COMPONENT PARTS REPLACEMENT 3. Remove hub and disc assembly. WHEEL HUBS, BEARINGS (Fig.
Page 195 FRONT SUSPENSION 3-17 brake discs for out-of-round or scored conditions and check bearing outer races for looseness in hubs. Repairs Replacement o f Bearing Cups If necessary to replace an outer race, drive out old race from the hub with a brass drift inserted behind race in notches in hub.
Page 196 3-18 FRONT SUSPENSION Fig. 24— Shock Absorber - C, P and G Typical NOTE: Slit in bar to frame bushings should be facing forward. 1. Place stabilizer in position on frame and install frame brackets over bushings. Install nuts and bolts loosely.
Page 197 FRONT SUSPENSION 3-19 Installation See CAUTION on page 1 of this CAUTION: section regarding the fasteners referred to steps 3 and 4. 1. Properly position spring on the control arm, and lift control arm using jack and tool J-23028. 2. Position control arm cross-shaft to crossmember and install “U”...
Page 198 3-20 FRONT SUSPENSION LOWER CONTROL ARM INNER PIVOT SHAFT AND/OR BUSHING REPLACEMENT C20-30, G30, P10-30 (Steel Bushings) Lower— Removal (Fig. 29) 1. Raise vehicle and support the frame so that control arms hang free. 2. Position an adjustable floor jack under the control arm inboard of spring and into depression in lower arm.
Page 199 FRONT SUSPENSION 3-21 Installation See CAUTION on page 1 of this J— 24435-7 CAUTION: section regarding the fasteners referred to in steps 4 and 5. 1. Install shaft to control arm and install end nuts. Do not torque nuts at this time. 2.
Page 200 3-22 FRONT SUSPENSION 2. Install remover J-24435-1, receiver J-24435-3 and LOWER CONTROL ARM ASSEMBLY "C" clamps J-24435-7 as shown in Figure 32A. Removal 3. Tighten the clamp to draw out the old bushing. 1. Raise vehicle on hoist and remove spring as Discard old bushing.
Page 201 FRONT SUSPENSION 3-23 J— 24435-7 J— 24435-7 J— 24435-6 Fig. 33B— Lower Control Arm Rubber Bushing Fig. 33C— Lower Control Arm Rubber Bushing Removal Installation 3. Install a chain over the upper arm inboard of the Be sure spacer J-24435-6 is in CAUTION: stabilizer and outboard of shock absorber as a position as shown in figure 33C to avoid...
Page 202 3 -2 4 FRONT SUSPENSION torque to align cotter pin not to exceed 130 ft. lbs. Never back off to align cotter pin. 4. Install new cotter pin. 5. Install lube fitting and lube new joint. 6. Install brake caliper assembly if removed (see section 5).
Page 203 FRONT SUSPENSION 3-25 caliper assembly and wire it to the frame to 7. Install Tools J-9519-10 and J-9519-7 as shown in Fig. 36. gain clearance for tool J-23742. See section 5 for proper procedure. NOTE: It will be necessary to alter Tool J-9519-10 as illustrated in Fig.
Page 204 3-26 FRONT SUSPENSION remains compressed, yet the wheel and steering knuckle assembly remain accessible. If a frame hoist is used, support lower control arm with an adjustable jackstand to safely retain spring in its curb height position. Removal 1. Raise vehicle on hoist and support lower control arm as noted above.
Page 205 FRONT SUSPENSION 3-27 FRONT SUSPENSION D IA G N O SIS HARD STEERING Probable Cause Probable Remedy a. Ball joints and steering linkage need lubrication a. Lubricate ball joints and linkage b. Low or uneven front tire pressure b. Inflate tires to the proper recommended pressure c.
Page 206 3-28 FRONT SUSPENSION NOISE IN FRONT END Probable Remedy Probable Cause a. Ball joints and steering linkage need lubrication a. Lubricate at recommended intervals b. Tighten bolts and/or replace bushings b. Shock absorber loose or bushings worn Worn control arm bushings c.
Page 207 FRONT SUSPENSION 3-29 “ DOG' ' TRACKING Probable Cause Probable Remedy LEAF TYPE REAR SPRING a. Rear leaf spring broken a. Replace spring b. Bent rear axle housing b. Replace housing c. Frame or underbody out of alignment c. Align frame COIL TYPE REAR SPRING a.
Page 208 3-30 FRONT SUSPENSION B A L L JO IN T DIAG NO STIC PROCEDURE Fig. 43— Ball Joint Diagnostic Procedure except K Series LIGHT DUTY TRUCK SERVICE MANUAL...
Page 209 FRONT SUSPENSION 3-31 the up and down motion stops very quickly. If up and SHOCK ABSORBER down motion continues longer at one corner when DIAGNO SIS compared to opposite corner (example, both front shocks), the one having the longer up and down motion ON VEHICLE CHECKS may be suspect.
Page 210 3-32 FRONT SUSPENSION movement of the front shocks during the compression stroke. Compare the rebound resistance between both front shocks, then compare the compression resistance. If a noticeable difference can be felt during either stroke, usually the shock having the least resistance is at fault.
Page 211 FRONT SUSPENSION 3-33 AIR ADJUSTABLE SHOCKS This type of shock contains an air chamber like the spiral groove reservoir type, and must have the air purged from the working chamber. See Section 1, Spiral Groove Reservoir. After air has been purged from shock, proceed as follows: (a) Clamp lower shock mounting ring in vise in vertical position with larger diameter tube at the...
Page 212: Diagnosis
3 -3 4 FRONT SUSPENSION DIAGNOSIS FRONT WHEEL, PINION, DIFFERENTIAL SIDE A N D REAR WHEEL ROLLER BEARINGS EXCESS NOISE COMPLAINT DIAGNOSTIC PROCEDURE Check tires for irregular wear Check tire pressure Road Test Check lubricant level Drive to warm-up rear axle Test at various speeds in drive, float, coast and cornering Change tire pressure to minimize noises Drive over different road surfaces...
Page 213: Front Suspension
FRONT SUSPENSION 3-35 FRONT WHEEL BEARING DIAGNOSIS CONSIDER THE FOLLOWING FACTORS WHEN DIAGNOSING BEARING CONDITION: 1. GENERAL CONDITION OF A LL PARTS DURING DISASSEMBLY AND INSPECTION. 2. CLASSIFY THE FAILURE WITH THE AID OF THE ILLUSTRATIONS. 3. DETERMINE THE CAUSE. 4.
Page 214 3-36 FRONT SUSPENSION FRONT WHEEL BEARING DIAGNOSIS (CONT’D) C R A C K E D I N N E R R ACE FATI GUE S P A L L I N G BR I NE L LI NG RACE CRACKED DUE TO IMPROPER FIT. FLAKING OF SURFACE METAL RESULTING FROM SURFACE INDENTATIO NS IN RACEWAY CAUSED BY COCKING, OR POOR BEARING SEATS.
Page 215 FRONT SUSPENSION 3-37 J-8457 Bearing Race Installer Driver Handle J-8092 J-8458 Bearing Race Installer J-9519-9 Ball Joint Installer J-8849 Bearing Race Installer J-9519-7 Ball Joint Remover J-9276-2 Bearing Race Installer J-9519-10 " C " Clamp Bushing Replacement Spring Remover J-24435-1 J-23028-01 thru 7 C 10, G 10-20...
Page 216 3-38 FRONT SUSPENSION FOUR WHEEL DRIVE (SERIES K10 AND K20) INDEX Removal................. 341 General Description............3-38 Installation..............343 Front Axle...............3-38 Disassembly..............343 Transfer Case..............3-38 Adapter Assembly............3-38 Wheel Hub..............344 Free Wheeling Hubs.............3-38 Spindle................. 344 Maintenance and Adjustments........3-39 Axle Joint..............344 Ball Joint Adjustment...........3-39 Ball Joint Service............
Page 217 FRONT SUSPENSION 3-39 MAINTENANCE AND ADJUSTMENTS 3. At top of knuckle, apply torque wrench to one of BALL JOINT ADJUSTMENT the steering arms attaching stud nuts, then check Front axle ball joint adjustment is generally necessary torque necessary to turn the steering knuckle. only when there is excessive play in steering, irregular Maximum torque should be: 20 ft.
Page 218 3-40 FRONT SUSPENSION COMPONENT PARTS REPLACEMENT 2. Slide inner clutch ring and bushing assembly from FREE-WHEELING HUB axle sleeve and clutch ring assembly. The free wheeling hub assemblies used on the front wheels are serviceable. Inspection 1. Wash all parts in solvent and air dry. 2.
Page 219 FRONT SUSPENSION 3-41 3. Place inner clutch ring and bushing assembly into of the bushing, to the splines and teeth of the axle shaft sleeve and clutch ring assembly and inner and outer clutch gears, and to the install as an assembly onto the axle shaft. Press in actuating cam.
Page 220 3-42 FRONT SUSPENSION SPRING RETAINER PLATE INNER CLUTCH RING ASSEMBLY AXLE SHAFT SNAP RING OUTER CLUTCH RETAINING RING AXLE SHAFT SLEEVE AND RING O " RING ACTUATING ACTUATOR KNOB CAM BODY " O " RING WASHER INTERNAL SNAP RING BUSHING HUB RING RETAINING KNOB AXLE SHAFT...
Page 221 FRONT SUSPENSION 3-43 Fig. 55— Front Drive Axle Assembly all fitting ends or cover with a rag to prevent 5. Connect brake hoses to frame fittings bleed the contamination. brake system (see Section 5). 5. Disconnect shock absorbers from axle brackets. 6.
Page 222 3-44 FRONT SUSPENSION 4. Remove the wheel bearing outer lock nut, lock ring, and wheel bearing inner adjusting nut using Tool J-6893 and Adapter J-23446 or tool J-6893-01. (See fig. 58). 5. Remove the disc assembly, outer wheel bearing and the spring retainer plate.
Page 223 FRONT SUSPENSION 3-45 Fig. 58— Removing Wheel Bearings Fig. 61— Removing Steering Arm Nuts 10. To remove the tie rod: a. Remove cotter pins. b. Loosen tie rod nuts and tap on nut with a soft hammer to break the studs loose from the knuckle arm.
Page 224 3-46 FRONT SUSPENSION J-6382-3 BALL JOINT fj- 2 3 4 5 4 - 2 Fig. 63— Removing Lower Ball Joint Fig. 65— Installing Lower Ball Joint before any service can be performed on the lower ball stud and the yoke and tapping on the tool to release the knuckle assembly.
Page 225 FRONT SUSPENSION 3-47 cotter pin hole in the stud end) is straight. Press the 6. Torque the upper ball socket nut to 100 ft. lbs. as stud into the knuckle until properly seated using shown in Figure 68. After torquing the nut, do not tools J-9519-10, J-23454-2, and J-6382-3 or equiva...
Page 226 3-48 FRONT SUSPENSION lbs. (while rotating hub) to seat the bearings using Assemble Spindle Components: Tool J-6893 and Adapter J-23446 or J-6893-01. Back a. Place the spindle in a vise on the high step and off the inner adjusting nut and retorque to 35 ft. install needle roller bearing using Installer lbs.
Page 227 FRONT SUSPENSION 3-49 SPECIAL TOOLS Bearing Race Installer 6. J-6382-3 1. J-6368 Sleeve 2. J-6893-01 Bearing Installer 7. J-23447 Adjusting Sleeve Spanner 8. J-23448 Cup and Seal Installer Driver Handle 3. J-8092 9. J-23454-1 Ball Joint Remover/Installer 4. J-9519 " C " Clamp Bearing Installer J-23454-2 Ball Joint Remover/Installer...
Page 229 REAR SUSPENSION AND DRIVELINE SECTION 4 REAR SUSPENSION AND DRIVELINE The following caution applies to one or more steps in the assembly procedure of components in this portion of the manual as indicated at appropriate locations by the terminology "See Caution on page 1 of this Section".
Page 230 4-2 REAR SUSPENSION AND DRIVELINE COMPONENT PARTS REPLACEMENT 5. Remove shock absorber from vehicle. SHOCK ABSORBERS 6. To install shock absorber, place into position and Replacement reattach at upper mounting location. Be sure to Refer to figures 4, 5, 6, 7 and 8 for specific vehicle install nuts and washers as shown.
Page 231 REAR SUSPENSION AND DRIVELINE Fig. 8— Shock Absorber— P30 4. Remove brackets from anchor plates by removing STABILIZER SHAFTS attaching screws. Refer to figures 9, 10 and 11 for specific rear stabilizer 5. Remove stabilizer shafts. shaft mounting on C and P models. 6.
Page 232 4-4 REAR SUSPENSION AND DRIVELINE *NOTE: Torque nut by running nut to unthreaded portion o f link bolt. Fig. 11— Rear Stabilizer Shaft— P-30 Fig. 10— Rear Stabilizer Shaft— C-20(63), C-30 2. Loosen, but do not remove, spring-to-shackle LEAF SPRING ASSEMBLY retaining nut.
Page 233 REAR SUSPENSION AND DRIVELINE Fig. 13— Rear Spring I nstallation— C-K Models LIGHT DUTY TRUCK SERVICE MANUAL...
Page 234 4-6 REAR SUSPENSION AND DRIVELINE Fig. 15— Rear Spring Installation— P30 Bushing Replacement Spring Leaf Replacement 1. Place spring on press and press out bushing using a 1. Place spring assembly in a bench mounted vise and suitable rod, pipe or tool as shown in figure 16. remove spring clips.
Page 235 REAR SUSPENSION AND DRIVELINE Leaf Spring Installation SHACKLE REPLACEMENT 1. Raise vehicle on hoist. Place adjustable lifting 1. Position spring assembly to axle. Make sure spring device under axle. is in position at both spring hangers. 2. Remove load from spring by jacking frame. NOTE: The shackle assembly must be attached to the rear spring eye before 3.
Page 236 4-8 REAR SUSPENSION AND DRIVELINE PROPELLER SHAFT INDEX ........... 4-8 Theory of Operation....Component Parts Replacement ........... 4-9 the alternate deceleration and acceleration of the second THEORY OF OPERATION joint. When the two joints do not run at approximately Universal Joints the same angle, operation can be rough and an objectionable vibration can be produced.
Page 237 REAR SUSPENSION AND DRIVELINE length, diameter and the type of splined yoke. On some models the drive shaft is made up of concentric steel tubes with rubber elements between. Each shaft is installed in the same manner. A universal joint and splined slip yoke are located at the transmission end of the shaft, where they are held in alignment by a bushing in the transmission rear extension.
Page 238 4-10 REAR SUSPENSION AND DRIVELINE Removal 1. Raise vehicle on hoist. Mark relationship of shaft to companion flange and disconnect the rear universal joint by removing trunnion bearing "U" bolts or straps. Tape bearing cups to trunnion to prevent dropping and loss of bearing rollers. 2.
Page 239 REAR SUSPENSION AND DRIVELINE 4-11 CENTER SUPPORT BEARING— FIG. 27 CAUTION: See CAUTION on page 1 of this section regarding Center Support Bearing fasteners. 1. Remove dust shield. 2. Remove strap retaining rubber cushion from bearing support. 3. Pull support bracket from rubber cushion and pull cushion from bearing.
Page 240 4-12 REAR SUSPENSION AND DRIVELINE c. Start bearing and slinger assembly straight on shaft journal. Support propeller shaft and, using ALIGNMENT suitable length of pipe over splined end of shaft, press bearing and inner slinger against shoulder on shaft. d. Install dust shield over shaft, small diameter first and press into position against outer slinger.
Page 241 REAR SUSPENSION AND DRIVELINE 4-13 8. Remove front trunnion from center and front yoke in same manner as described in Steps 2, 3 and 4. NOTE: Before front trunnion can be removed all four (4) bearing caps must be removed. Assembly 1.
Page 242 4 -1 4 REAR SUSPENSION AND DRIVELINE PROPELLER SHAFT AND UNIVERSAL JOINT D IAG N O SIS 4. Stop engine and check for any mud or undercoat Checking and Correcting ing on the propeller shaft. If any is found, remove Propeller Shaft Unbalance—...
Page 243 REAR SUSPENSION AND DRIVELINE 4-15 C O M P L A IN T P O S S IB L E C A U S E C O R R E C T IO N Roughness, Vibration or a. Bent or dented drive shaft. a.
Page 244 Five distinct axles compromise the truck line-up. These five, categorized by ring gear diameter, are a) 8-7/8" Ring Gear, b) Chevrolet 10-1/2" Ring Gear, c) Dana 10-1/2" Ring Gear, d) Dana 9-3/4" Ring Gear and e)Chevrolet 12- 1/4" Ring Gear.
Page 245 Pinion depth is Chevrolet 10 -1/2 " Ring Gear Axle The axle shown in figure 35 is of the full floating type controlled by a shim located between the pinion bearing with hypoid ring gear and drive pinion.
Page 246 4-1 8 REAR SUSPENSION AND DRIVELINE P inion Rear Bearing P inion N u t D iffe re n tia l Spider Washer Drive P inion D iffe re n tia l Side Geai Ring Gear Washer C om panion Flange P in ion Gear O il Seal D iffe re n tia l Case...
Page 247 REAR SUSPENSION AND DRIVELINE 4-19 1. Nut 11. Shims (Inner Pinion 24. Bolt (Differential 17. Cover and Plug Bearing) Bearing Cap) 2. Washer Lock Pin (Pinion 12. Cup (Inner Pinion 3. Companion Flange Shaft) 25. Bolt (Ring Gear) 4. Pinion Oil Seal Bearing) 26.
Page 248 4-20 REAR SUSPENSION AND DRIVELINE Fig. 37— 12-1/4" Ring Gear Axle— 11,000# Capacity and also between differential pinions and the differential 12 -1/4 " Ring Gear Axle case. (11,000 Pound Capacity) A thrust pad mounted on the end of an adjusting screw The 11,000 lb.
Page 249 REAR SUSPENSION AND DRIVELINE 4-21 THEORY OF OPERATION- STANDARD DIFFERENTIAL The differential has two basic functions. First, it transmits torque from the propeller shaft, through a 90° turn, to the rear wheels. Second, it takes the torque provided by the propeller shaft and divides this torque as necessary to allow each wheel enough torque to rotate as conditions require.
Page 250 4-22 REAR SUSPENSION AND D R IV E L IN E Differential Operation A differential is an arrangement of gears that divides the torque between the axle shafts and allows them to rotate at different speeds. A basic differential consists of a set of four gears.
Page 251 REAR SUSPENSION AND D R IV E L IN E 4-23 mishandling in storage and installation. They are portion of the outer race can be exposed. In cases where adversely affected by dirt and they should be protected the entire face of the outer race is exposed, a section of from rust and corrosion.
Page 252 4 -2 4 REAR SUSPENSION AND DRIVELINE Installation Procedures Before pressing a bearing back on the shaft, the bearing seat should be thoroughly cleaned of all dirt, carbonized lubricant or any other foreign matter present. Not only may such things cause scoring of the shaft and the bearing bore, but an improper bearing installation may result.
Page 253 REAR SUSPENSION AND DRIVELINE 4-25 PRESS RAM STEEL "* BLOCK PIPE OR TUBE Fig. 48— Bearing Installation Using Arbor Press Fig. 46— Applying Pressure on the Correct Race action is rapid and pressure can be applied continuously. Special precaution should be taken when using the arbor press to align the race squarely on the shaft, as the great pressures which can be exerted by the press could easily cause race cracking or severe scoring of the shaft, if the...
Page 254 4 -26 REAR SUSPENSION AND DRIVELINE 6. Never hammer directly on races or rollers, and never use a wooden or soft metal mallet, as chips or splinters may enter the bearing. 7. Use many smart quick taps rather than a few heavy ones.
Page 255 REAR SUSPENSION AND DRIVELINE 4-27 Fig. 51— Differential Pinion Shaft Removal Fig. 53— Wheel Bearing Removal Oil Seal/Bearing— Replacement 1. Remove oil seal by using button end of axle shaft. Insert button end behind the steel case of the oil seal, then pry seal out of bore being careful not to damage seal.
Page 256 4-2 8 REAR SUSPENSION AND DRIVELINE Fig. 55— Seal Installation Fig. 56— Pressing Out Wheel Stud Axle Shaft— Installation 6. Remove lug nut. 1. Slide axle shaft into place. 7. Reinstall brake drum and wheel and tire. Exercise care that splines on end of CAUTION: 8.
Page 257 REAR SUSPENSION AND DRIVELINE 4-29 the number of exposed threads on pinion stem, and record for later reference. See figure 58. 6. Install Tool J-8614-11 on pinion flange and remove pinion flange self-locking washer faced nut as shown in figure 59. (Position J-8614-11 on flange so that the four notches are toward flange.) Save scribed nut for reinstallation.
Page 258 7. 7. Test operation of brakes and rear axle. 8. Lower vehicle and remove from hoist. AXLE SHAFT CHEVROLET 10-1/2 RING Replacement GEAR AXLES 1. Remove bolts and lock washers that attach the axle shaft flange to the wheel hub. See figure 63.
Page 259 REAR SUSPENSION AND DRIVELINE 4-31 Fig. 65— Removing Lock Nut— Typical Fig. 63— Removing Flange-to-Hub Bolts 3. Disengage tang of retainer from slot or flat of adjusting nut and remove retainer from housing HUB AND DRUM ASSEMBLY— FIG. 64 tube. Removal 4.
Page 260 4-32 REAR SUSPENSION AND DRIVELINE Inspection and Cleaning o f Bearings 1. Inspect bearing rollers for excessive wear, chipped edges, and other damage. Slowly move rollers around cone to detect any flat or rough spots on rollers or cone. 2. Examine bearing cups in hub for pits, cracks, and other damage.
Page 261 Procedures for service to axle assembly, axle shafts, hub See figure 68, and refer to Specifications Section for and drum components and bearing adjustments are identical to those listed for "Chevrolet 10-1/2 Ring Gear torque values. Axle". 4. Install tanged retainer against the inner adjusting Drive pinion oil seal replacement requires different nut.
Page 262 Torque bolts to specifications. HUB AND DRUM ASSEMBLY— FIG. 71 Removal Use the procedure given for "Chevrolet 10-1/2" Ring Gear Axle", and use J-0870 to remove the adjusting nut. Refer to figure 65. Fig. 70— Removing Axle Shaft— 11,000 # Axle Bearing Cup—...
Page 263 REAR SUSPENSION AND DRIVELINE 4-35 Fig. 75— Installing Hub Inner Bearing Cup NOTE: The bearing cup-to-retainer ring seating procedure is essential to assure that an accurate wheel bearing adjustment will be obtained, and that the adjustment will not loosen during vehicle operation. 5.
Page 264 WHEEL BOLT REPLACEMENT 1. Disconnect propeller shaft. Refer to figure 67 and to procedure listed under "Chevrolet 10-1/2" Ring Gear Axle. 2. Scribe a line down the pinion stem, pinion nut and companion flange. 3. Use J-8614-11 to remove the pinion nut and the companion flange.
Page 265 REAR SUSPENSION AND DRIVELINE 4-37 DIFFERENTIAL D IA G N O SIS STANDARD DIFFERENTIAL Degree of Noise Any gear driven unit, and especially an automotive drive Noise axle where engine torque multiplication occurs at a 90° The most essential part of rear axle service, as with any turn in the drive line, produces a certain amount of mechanical repair, is proper diagnosis of the problem, and, in noise.
Page 266 4 -3 8 REAR SUSPENSION AND DRIVELINE Elimination of External Noises Body Boom Noise or Vibration When a rear axle is suspected of being noisy, it is Objectional "body boom" noise or vibration at 55-65 advisable to make a thorough test to determine whether mph can be caused by an unbalanced propeller shaft.
Page 267 REAR SUSPENSION AND DRIVELINE 4-39 produce a constant rough noise of a lower Side Bearings pitch than pinion bearings. Side bearing noise may also fluctuate in the above wheel bearing test. NOTE: Bearing Diagnosis Charts appear later in this section. Gear Noise There are two basic types of gear noise.
Page 268 4 -4 0 REAR SUSPENSION AND DRIVELINE A G E N E R A L D IA G N O S T IC P R O C E D U R E F O R IS O L A T IN G R E A R A X L E N O IS E P R O B L E M S Cause Problem 1.
Page 269 REAR SUSPENSION AND DRIVELINE 4-41 DIFFERENTIAL AND REAR AXLE BEARING DIAGNOSIS CONSIDER THE FOLLOWING FACTORS WHEN DIAGNOSING BEARING CONDITION GENERAL CONDITION OF A LL PARTS DURING DISASSEMBLY AND INSPECTION. CLASSIFY THE FAILURE WITH THE AID OF THE ILLUSTRATIONS. 3. DETERMINE THE CAUSE. 4 MAKE ALL REPAIRS FOLLOWING RECOMMENDFD PROCEDURES A B R A S I V E ROLLER...
Page 270 4-42 REAR SUSPENSION AND DRIVE LINE DIFFERENTIAL A N D REAR AXLE BEARING DIAGNOSIS (CO NT’D) C R A CK E D IN NER RACE FATIGUE SPALLING BRINELLING RACE CRACKED DUE TO IMPROPER FIT, SURFACE IN D E N TA TIO N S IN RACEWAY CAUSED BY FL A K IN G OF SURFACE M E TA L RESULTING FROM COCKING, OR POOR BEARING SEATS.
Page 271 8. J-6627 Wheel Bolt Remover 23. J-24428 Wheel Hub Oil Seal Installer 9. J-8092 Driver Handle 24. J-24434 Pinion Oil Seal Installer - Chevrolet 10. J-5853 Torque Wrench - Inch/Pound 25. J-870 Wheel Bearing Nut Wrench 11. J-8614-11 Companion Flange Holder 26.
Page 273 SECTION 5 BRAKES The following caution applies to one or more steps in the assembly procedure of components in this portion of the manual as indicated at appropriate locations by the terminology "See Caution on page 1 of this section.". CAUTION: THIS FASTENER IS AN IMPORTANT ATTACHING PART IN THAT IT COULD AFFECT THE PERFORMANCE OF VITAL COMPONENTS AND SYSTEMS, AND/OR COULD RESULT...
Page 274 5-2 BRAKES GENERAL DESCRIPTION All vehicles are equipped with a dual hydraulic brake valve is located below the master cylinder on P models (without Hydro-boost), on the crossmember on C-K system. models and P models (with Hydro-boost) or on the frame The split system consists basically of two separate brake rail on G models.
Page 275 BRAKES Fig. 1 -Master Cylinder Mountings-Typical LIGHT DUTY TRUCK SERVICE MANUAL...
Page 276 5-4 BRAKES PRIMARY SHOE PULL BACK SPRINGS FWD"*v DOWN SECONDARY SPRING SHOE AND PIN ACTUATING LEVER Fig. 3-Rear Drum Brake (Typicai Duo-Servo) Fig. 2--Front Disc Brake (Typical) THEORY OF OPERATION Brakes are simply a means of applying friction to either The basic hydraulic brake system consists of (1) a master cylinder, in which the hydraulic pressure is developed, stop, slow down or hold an element.
Page 277 BRAKES is pushed forward. The fluid in the master cylinder, and This is the principle that enables us to incorporate a very the entire system, being incompressible, transmits the desirable feature in the brake system - we can vary the force exerted by the master cylinder piston to all the braking power to the wheels by changing the wheel inner surfaces of the system.
Page 278 5-6 BRAKES COVER RETAINING BAIL RUBBER DIAPHRAM RESERVOIR COVER Fig. 6-Master Cylinder (Typical) Fig. 8-Front Line Failure (Typical) Fig. 7-Rear Line Failure (Typical) sufficient hydraulic pressure will be generated to operate Front Line Failure (Fig. 8) the rear brakes. It should be noted that if either the front or rear brakes If there is a malfunction in the front brake line, both become inoperative, one brake system will remain pistons will move forward when the brakes are applied,...
Page 279 BRAKES incorporated into the brake system. The dash-mounted Brakes Not Applied (Fig. 11) warning light will come on when the brakes are applied under a condition of partial failure. This is a signal to The metering valve allows free flow of brake fluid the driver to have the brakes serviced.
Page 280 5-8 BRAKES SWITCH TERMINAL SWITCH PIN ,REAR ,NLET PORT PROPORTIONER PISTON FRONT INLET PORT — . SWITCH PISTON FRONT OUTLET STOP PLATE PORT BOOT PROPORTIONING N UT' DIAPHRAGM REAR OUTLET PORT 'METERING VALVE SEAL FRONT OUTLET PORT METERING VALVE STEM Fig.
Page 281 BRAKES FROM MASTER CYLINDER REAR OUTLET multiplied several times over the force applied at the brake pedal (fig. 18). Proper service of the brake pedal is vital to good brake Fig. 14--Rear System Failure performance, and pedal operation should be checked each time brakes are inspected.
Page 282 5-10 BRAKES CONTACT IS MADE Fig. 18-Brake Pedal (Typical) Fig. 17~Stoplamp Switch (Typical) through the bleeder holes in piston heads and past the pistons are held against the push rod retainer, and the primary seals are held just clear of the compensating primary seals to keep the pressure chamber filled.
Page 283 BRAKES 5-11 M O U N T IN G PLATE CALIPER SLIDES INBOARD W HEN BRAKES ARE APPLIED PISTON FRONT CALIPER ■ BRAKE LINE ASSEMBLY PISTON SEAL OUTBOARD SHOE FIXED TO CALIPER INBOARD SHOE REACTED O N BY PISTON BRAKE DISC Fig.
Page 284 5-12 BRAKES sleeve and groove in the housing, and an outer caliper rubber bushing is installed between each bolt and groove in the housing. On Hydro-boost vehicles, the caliper is mounted between machined surfaces of the steering knuckle and held in place by a spring and support key. Shoe and lining assemblies are positioned on the caliper so they straddle the disc.
Page 285 BRAKES 5-13 When the brakes are applied with the vehicle moving in reverse, the rear shoe becomes, in effect, the primary shoe. The self-energizing action now would be applied to the front shoe, and the rear shoe would move away from the anchor pin.
Page 286 5 -1 4 BRAKES rotation of the secondary or rear shoe is toward the Over-Ride Mechanism (Fig. 26) anchor pin, the effective distance from the pin to the All of the standard equipment self-adjusting mechanisms actuating lever is not increased; thus, no adjustment contain a built-in safety device known as the "over-ride occurs.
Page 287 BRAKES 5-15 The adjuster assembly is similar to that used on the duo- servo brake described previously. STOP TANG SEATED ON SHOE Self Energizing Action The brakes are self-energizing. This means that the brake unit is designed to assist the driver in forcing the shoes against the drum.
Page 288 5-16 BRAKES If brake fluid becomes contaminated, it may lose some (drums, rotors, wheel cylinders, etc.). For convenience, it of its original qualities. It is good practice to bleed the is recommended that disc brake pads be checked brake system until all old fluid is removed when whenever tires are rotated (at 6000 mile intervals).
Page 289 BRAKES 5-17 master cylinder may enter a line farther away after it until all valves have been bled and there is has been bled. no evidence of air in the system. 4. Pour a sufficient amount of brake fluid into a CAUTION: Do not perform bleeding operation transparent container to ensure that end of bleeder while any brake drum is removed or with a...
Page 290 5-18 BRAKES position while bleeding. This can be accom cover, the retaining bail should be slipped over plished by installing Tool J-23709 with the the lower cover bosses (fig. 31). Incorrect open slot under the mounting bolt and installation could result in bail tension loss and pushing in on the pin in the end of the valve fluid leakage.
Page 291 BRAKES 5-19 hose replacement has not caused the support bracket to loosen; retorque bracket attachment if required. See Caution on Page 1 of this CAUTION: section. 5. Bleed brakes as outlined in this section. Hydraulic Brake Tubing (Figs. 34 thru 38) Hydraulic brake tubing used on all trucks is a double wall steel tubing which resists corrosion and has the physical strength to stand up under the pressures which...
Page 292 5-20 BRAKES edges with reamer tool provided on the tube cutter. 2. Install compression couplings on tubing and dip end of tubing to be flared in hydraulic brake fluid. This lubrication results in better formation of the flare. 3. Place one-half of the die blocks in the tool body with the counterbored ends toward the ram guide.
Page 293 BRAKES 5-21 Fig. 3 5 -Single and Double Lap Flare Recommended Method of Adjustment (Fig. 39) a. Use Drum to Brake Shoe Clearance Gauge J-21177 or J-22364 to check the diameter of the drum clearance surface (fig. 39). b. Turn the tool to the opposite side and fit over the brake shoes by turning the star wheel until the gauge just slides over the linings (fig.
Page 294 5-22 BRAKES INITIAL PEDAL HEIGHT (Brakes Not Applied) POWER " X " MODEL SYSTEM DIM. VACUUM 4.60 VACUUM 4.88 HYDRO-BOOST 6.18 P ( 42) VACUUM 4.16 P ( 42) HYDRO-BOOST 5.80 WITH COVER O N REMOVE MAT AND CARPET Fig. 41-Brake Pedal Adjustment-Typical Fig.
Page 295 BRAKES 5-23 6. Fully release parking brake and rotate rear wheels. PARKING BRAKE-REAR WHEEL No drag should be present. The rear brake assemblies (except RPO H22--where 7. Remove vehicle from hoist. parking brake is mounted on the propeller shaft) serve a dual purpose in that they are utilized both as a hydraulically operated service brake and also as a PARKING BRAKE (PROPELLER S H A F T)-...
Page 296 5 -2 4 BRAKES COMPONENT REPLACEMENT AND REPAIRS 1. Raise the vehicle on hoist. SHOES AND LININGS— REAR DRUM 2. Loosen the parking brake equalizer nut sufficiently BRAKES (Fig. 43) to remove all tension from brake cable. NOTE: If brake drums are worn severely, it may be necessary to retract the adjusting 3.
Page 297 BRAKES 5-25 wet with brake fluid. Excessive fluid at this point indicates leakage past piston cups requiring overhaul of wheel cylinder. NOTE: A slight amount of fluid is nearly always present and acts as lubricant for the piston. 3. Inspect flange plate for oil leakage past axle shaft oil seals.
Page 298 5-26 BRAKES 4. Before installation, make certain the adjusting screw is clean and lubricated properly. CAUTION: Loose adjustment may occur from an adjusting screw that is not properly operating. I f the lubricant in the adjusting screw assembly is contaminated or destroyed, the adjusting screw should be thoroughly cleaned and lubricated with Delco Brake Lube #5450032 (or equivalent).
Page 299 BRAKES 5-27 rivets out will distort shoe rim. Thoroughly clean leaking fluid. Wheel cylinders having torn, cut, or heat- surface of shoe rim and file off any burrs or high cracked boots should be completely overhauled. spots. 2. Use released brake lining (or equivalent) and the Wheel Cylinder Repair rivets included in lining package which are of the Wheel cylinders should not be disassembled unless they...
Page 300 5-28 BRAKES A cracked drum is unsafe for WARNING: further service and must be replaced. Do not PUSH ROD AND BOOT attempt to weld a cracked drum. PISTON CUP RETURN SPRING WITH EXPANDERS Smooth up any slight scores by polishing with fine emery cloth.
Page 301 BRAKES 5-29 difference between these 4 readings must not exceed wheels are removed. Check both ends of the outboard .006. shoe by looking in at each end of the caliper. This is the point at which the highest rate of wear normally occurs. At the same time, check the lining thickness on the Cleaning inboard shoe by looking down through the inspection...
Page 302 5-30 BRAKES 2. Examine the inside of the caliper for evidence of fluid leakage. If leakage is noted, the caliper should be overhauled. 3. Wipe the inside of the caliper clean, including the exterior of the dust boot. Check the boot for cuts, "C”...
Page 303 BRAKES 5-31 Fig. 58—Fitting Shoe to Caliper 5. Push down until the shoe lays flat against the the mounting bracket, making sure that the ends of caliper (fig. 57). the bolts pass under the retaining ears on the inboard shoe. 6.
Page 304 5-32 BRAKES Fig. 59-Caliper Explode 3. Push the piston back into its bore. This can be CALIPER OVERHAUL accomplished by using a "C" clamp as shown in Always use clean brake fluid to Figure 53. CAUTION: clean any caliper parts. Never use mineral-base cleaning solvents such as gasoline, kerosene, 4.
Page 305 BRAKES 5-33 Do not place the fingers in front The use of lubricated shop air will WARNING: CAUTION: of the piston in an attempt to catch or protect leave a film of mineral oil on the metal parts. it when applying compressed air. This may damage rubber parts when they come in contact after reassembly.
Page 306 5 -3 4 BRAKES Brake discs can be refinished if precision equipment is 4. Position the dust boot in the caliper counterbore available and a few simple rules are followed. The first and seat using Boot Installer Tool J-22904 as shown in Figure 62.
Page 307 BRAKES 5-35 Fig. 66--Checking Surface Parallelism 5. WHEN MOUNTED ON BEARING CUPS, LATERAL RUN-OUT MUST NOT EXCEED .005 T.I.R. AND MAXIMUM RATE OF CHANGE MUST NOT EXCEED .001 IN 30°. Proper lateral runout will prevent disc "wobble" that could knock the piston back into the caliper bore causing increased pedal travel.
Page 308 5-36 BRAKES press it down over the push rod retainer. Slide new mounting gasket into position. Secure the master cylinder to the dash panel with mounting bolts or stud nuts. CAUTION: See " Caution" on Page 1 of this section. 3.
Page 309 BRAKES 5-37 each rubber part for cuts, nicks or other damage. These parts are the key to the control of fluid flow. If the unit is in for overhaul, or if there is any question as to the serviceability of rubber parts, REPLACE them. Badly damaged items, or those which would take extensive work or time to repair, should be replaced.
Page 310 5-38 BRAKES 7. Reposition master cylinder in vise so that the front 4. Coat the bore of the master cylinder with clean brake fluid. Coat the primary and secondary seals end is tilted slightly up. on the secondary piston with clean brake fluid. 8.
Page 311 BRAKES 5-39 Proportioning Valve combination valve must be held in the open The function of this valve is prevent premature rear position (not allowed to close). This can be wheel slide. Line pressure is allowed to increase normally accomplished by installing Tool J-23709 up to a certain point (determined by vehicle weight and under the mounting bolt and depressing the braking distribution).
Page 312 5-42 BRAKES Fig. 73--Parking Brake System (Typical) LIGHT DUTY TRUCK SERVICE MANUAL...
Page 313 BRAKES 5-43 RETURN SPRINGS WAVE WASHER FLANGE LOCK BRAKE LEVER WASHER SHOE ANCHOR HOLD GUIDE DOWN STRUT PLATE SPRING WASHER DRUM HOLD DOWN SPRING WASHER. SPRING , CUP SOCKET ADJUSTING SCREW BACKING BRAKE PLATE CABLE Fig. 7 4 -Internal Expanding Brake Components tang of washer over reinforcement and side of 12.
Page 314 5-44 BRAKES ACTUATING LEVER ANCHOR ADJUSTING CAM SUPPORT ACTUATING FRICTION LEVER LINK SPRING OVER RIDE LEVER OVER RIDE SPRING RETURN SPRING HOLD DOWN ACTUATING STAR LEVER WHEEL Fig. 75-Rear Brake-Used with RPO H-22 lever and hold the lever away from the star wheel. Using a brake adjusting tool, back off the star wheel.
Page 315 BRAKES 5-45 and rust from shoe contact faces on flange plate using emery cloth. 13. Thoroughly clean adjusting screws and threads in the anchor brackets. Installation 1. Put a light film of Delco Brake Lube #5450032 (or equivalent) on shoe bearing surfaces of brake flange plate and on threads of adjusting screw.
Page 316 5-46 BRAKES 10. Locate the adjusting lever .020" to .039" above the outside diameter of the adjusting screw thread by loosening the cap screw and turning the adjusting cam. NOTE: To determine .020" to .039", turn the adjusting screw 2 full turns out from the fully retracted position.
Page 317 BRAKES 5-47 with continuous applications during test. Refer to the General Checks Troubleshooting Chart for causes and remedies for NOTE: If a damaged component or malfunc trouble which may be discovered during testing. tion is discovered while making any of the following brake system checks, repairs must be made before attempting to continue with WARNING: Before driving any vehicle, push...
Page 318 5-48 BRAKES D IA G N O SIS— DRUM BRAKES LOW PEDAL OR PEDAL GOES TO TOE BOARD Remedy Probable Cause 1. Excessive clearance between li n i n g s and drum. Adjust brakes. 2. Automatic adjusters not working. 2.
Page 319 BRAKES 5-49 D IA G N O SIS— DRUM BRAKES EXCESSIVE PEDAL PRESSURE REQUIRED TO STOP (CONT.) Probable Cause Remedy 7. Glazed li n i n g s . 7. Sand surface of li n i n g s . 8.
Page 320 5-50 BRAKES D IA G N O SIS— DRUM BRAKES * BRAKES FADE Probable Cause Remedy 1. Replace with new l in in g or shoe and lin in g assembly, 1. Incorrect 1ining. 2. Replace drums. 2. Thin drum. 3.
Page 321 BRAKES 5-51 D IA G N O SIS— DRUM BRAKES REAR BRAKES DRAG Probable Cause Remedy 1. Maladjustment. 1. Adjust brake shoes and parking brake mechanism. 2. Parking brake cables frozen. 2. Lubricate with Delco Brake Lube #5450032 (or equivalent). PULLS TO ONE SIDE Probable Cause Remedy...
Page 322 5-52 BRAKES D IA G N O SIS— DRUM BRAKES ONE WHEEL LOCKS Remedy Probable Cause 1 . Gummy lin in g . 1. Replace the li n i n g s . 2. Tire tread s li c k . 2.
Page 323 BRAKES 5-53 D IA G N O SIS— DRUM BRAKES BRAKES CHATTER Probable Cause Remedy 1. Incorrect lin in g to drum clearance. 1 . Readjust to recommended clearances. 2. Loose flange plate. 2 . Tighten securely. 3. Grease, flu id , road dust on lin in g . 3 .
Page 324 5 -5 4 BRAKES D IA G N O SIS— DRUM BRAKES GRINDING NOISE Probable Cause Remedy Switch drums or grind drums. 1. Shoe h its drum. 2. Replace shoe and li n i n g assemblies. 2. Bent shoe web. 3.
Page 325 BRAKES 5-55 D IA G N O SIS— DISC BRAKES BRAKE ROUGHNESS, ETC. (CONT.) Probable Cause Remedy 4. Rear drums out-of-round. 4. Check runout and i f not within sp e c ific a t io n s , turn the drums.
Page 326 5-5 6 BRAKES D IA G N O SIS— DISC BRAKES DRAGGING BRAKES (CONT. Remedy Probable Cause 3. Check and readjust to correct specifications. 3. Incorrect parking brake adjustment on rear brakes. 4. Port marked "i n l e t " goes to master cylinder, Port 4.
Page 327 BRAKES 5-57 VACUUM POWER BRAKES INDEX General Description..............5-57 Theory of Operation..............5-57 Maintenance and Adjustments........... 5-63 Inspection..................5-63 Lubrication..................5-64 Bleeding..................5-64 Air Cleaner Service..............5-64 Component Part Replacement............ 5-64 Power Brake Unit................ 5-64 Diagnosis..................5-6 5 GENERAL DESCRIPTION The Power brake Unit is a self-contained hydraulic and less pedal effort than is required with the conventional vacuum unit, utilizing manifold vacuum and atmospheric...
Page 328 5-58 BRAKES Fig. 82-Typical Power Unit ■ Released both sides of the power piston. Any air in the system is RELEASED (Figs. 82 and 83) drawn through a small passage in the power piston, over At the released position the air valve is seated on the the valve seat in the power piston insert, and then floating control valve.
Page 329 BRAKES 5-59 Fig. 83-Typical Circuit - Released In this position there is vacuum on both sides of the piston. The floating control valve assembly is held power piston, and the power piston is held against the against the air valve seat by the floating control valve spring.
Page 330 5 -60 BRAKES VACUUM REACTION PLATE FLOATING CONTROL VALVE AIR VALVE UNSEATED AIR VALVE REACTION LEVERS ATMOSPHERIC PRESSURE Fig. 8 4 -Typical Power Unit - Applying power piston, and air under atmospheric pressure enters APPLYING (Figs. 84 and 85) through the air filter and travels past the seat of the air As the pedal is depressed, the valve operating rod (push valve and through a passage into the housing at the rear rod) carries the air valve away from the floating control...
Page 331 BRAKES 5-61 Fig. 8 5 -Typical Circuit - Applying As the power piston travels forward, the master cylinder the master cylinder piston, the hydraulic reaction plate is piston rod carries the master cylinder primary piston moved off its seat on the power piston and presses further into the bore of the master cylinder.
Page 332 5-62 BRAKES VACUUM REACTION PLATE FLOATING CONTROL VALVE AIR VALVE SEATED AIR VALVE REACTION LEVERS ATMOSPHERIC PRESSURE Fig. 86-Typical Power Unit ■ Holding Since both sides of the power piston are now under HOLDING (Figs. 86 and 87) vacuum, the power piston return spring will return the When the desired pedal pressure is reached, the power piston to its released position against the rear housing.
Page 333 BRAKES 5-63 Fig. 8 7 -Typical Circuit - Holding the hydraulic reaction plate. Since the hydraulic reaction VACUUM FAILURE plate is fastened to the master cylinder piston rod, it In case of vacuum source interruption, the brake unit operates in the following manner: forces the piston rod against the master cylinder primary piston, which builds up the hydraulic line pressure.
Page 334 5 -6 4 BRAKES engine should not be running and the vacuum reserve LUBRICATION should be reduced to zero by applying the brake several The power brake unit is lubricated at assembly and times before starting the bleeding procedure. needs no further lubrication other than maintaining normal reservoir fluid level.
Page 335 BRAKES 5-65 DIAGNO SIS NOTE: The same types of brake troubles are encountered with power brakes as with standard brakes. Before check ing the power brake system for source of trouble, refer to trouble diagnosis of standard hydraulic brakes in this manual.
Page 336 5-66 BRAKES DIAGNOSIS— POWER HYDRAULIC BRAKES SLOW BRAKE PEDAL RETURN Probable Cause Remedy Overhaul un it as outlined in the "Overhaul" Manual. 1. Excessive seal f r i c t io n in power unit. Overhaul unit. 2. Faulty valve action. 3.
Page 337 BRAKES 5-67 HYDRO-BOOST INDEX General Description............5-67 Brake Pedal Adjustment..........5-71 Booster................5-67 Stoplamp Switch Adjustment........5-71 Accumulator..............5-68 Component Part Replacement........5-72 Caliper................5-68 Hydraulic Brake Booster..........5-72 Theory of Operation............5-69 Brake Pedal Rod............5-73 Maintenance and Adjustments........5-70 Accumulator..............
Page 338 5 68 BRAKES Fig. 8 9 -Cross Section of Booster Components in Released Position ACCUMULATOR A spring accumulator (fig. 90) is used in conjunction with the hydraulic brake booster. The accumulator is a sealed hydraulic cylinder with a port at each end. Do not attempt to disassemble or WARNING: cut into the accumulator.
Page 339 BRAKES 5-69 THEORY OF OPERATION A schematic view of a Hydraulic Booster Brake System is from the power steering gear also lead back to the pump shown in Figure 92. Note that the output of the power reservoir. steering pump is routed to the hydraulic booster power section.
Page 340 5-70 BRAKES fluid from the power steering pump is interrupted Applied Position (broken belt, engine failure, power steering pump failure, hose rupture, etc.). When the brake pedal is depressed, the input rod and piston move slightly forward. The lever assembly moves the sleeve forward to close off the four holes leading to the open center of the spool.
Page 341 BRAKES 5-71 7. Turn off the engine and check the fluid level in the reservoir; add fluid if necessary. 8. Lower the vehicle, start the engine and run at approximately 1500 rpm. Again, apply and release the brake pedal several times. Turn the steering wheel to full right and left.
Page 342 5-72 BRAKES bracket. Electrical contact should be made when 3. Tighten switch locknut and connect electrical pedal travel is 3/8 - 5/8". harness. COMPONENT PART REPLACEMENT NOTE: It should not be necessary to HYDRAULIC BRAKE BOOSTER disconnect the hydraulic lines from the Removal (Fig.
Page 343 BRAKES 5-73 support bracket nuts and remove the booster 11. Fasten the boot to the floorpan and compress the assembly. boot to 2.54" installed height; tighten the boot screws to 13-18 in. lbs. Refer to Figure 94. P30(32) Models - 12.
Page 344 5 -7 4 BRAKES LINKAGE BRACKET PEDAL PUSH ROD SUPPORT REAR BOOSTER PEDAL ROD LINKAGE BRACKET FRONT SUPPORT _____ ROD VIEW B LEVER BOOSTER REAR SUPPORT VIEW A Fig. 9 7 -Booster Installation - P30(32) Models the ends of the shoe resting in the steering knuckle. The bolt and bracket;...
Page 345 BRAKES 5-75 ACCUMULATOR MASTER CYLINDER BOOSTER GEAR GEAR MANUAL STEERING POWER STEERING Fig. 9 8 -Hydraulic Line Routing-C Model Shown as Typical 4. Remove the bolt at the caliper support key. Using a the caliper and spindle assembly that are in contact brass punch, remove the key and spring (fig.
Page 346 5-76 BRAKES Fig. 99-Accumulator Installation SUPPORT BRASS ROD Fig. 101-Removing the Caliper Support Key Clamp LIGHT DUTY TRUCK SERVICE MANUAL...
Page 347 BRAKES 5-77 Removal CAUTION: Clean dirt from hose to caliper connection before proceeding with removal. 1. Remove the hose to caliper bolt and cap or tape the Fig. 102-Removing Caliper from the Disc open connections to prevent dirt from entering the steering knuckle.
Page 348 5-78 BRAKES 3. Carefully examine the outside surface of the piston caliper and remove the piston by directing for scoring, nicks, corrosion and worn or damaged compressed air into the caliper inlet hole (fig. 105). plating. If any surface defects are detected, replace Use just enough air pressure to ease the piston.
Page 349 BRAKES 5-79 Installation NOTE: Installation of the caliper and mounting parts is the same for: "Shoe and Lining-Disc Brake" except for steps given below: 1. Connect the brake hose to the caliper using NEW copper gaskets. Hose must be properly positioned to CAUTION: prevent hose twist or misalignment.
Page 350 5 -8 0 BRAKES D IA G N O S IS - HYDRO - BOOST SYSTEM Before checking the hydraulic pow er booster for the source o f trouble, refer N O T E : to the trouble diagnosis procedures for Standard Brakes. A fter these possible causes have been eliminated, check for the probable cause and remedy as outlined below: NO BOOST - HARD PEDAL Preliminary Check...
Page 351 BRAKES 5-81 D IA G N O S IS - HYDRO - BOOST SYSTEM SLOW BRAKE PEDAL RETURN P robable Cause Remedy Excessive seal f r i c t i o n in booster. Replace a ll booster seals. Faulty spool action. Clean spool and replace a ll booster seals.
Page 352 5-82 BRAKES D IA G N O S IS - HYDRO - BOOST SYSTEM ACCUMULATOR LEAKDOWN - SYSTEM DOES NOT HOLD CHARGE Preliminary Check Start engine and turn the steering wheel u ntil the wheels contact the wheel stops ligh tly. Hold fo ra maximum of five seconds.
Page 353 BRAKES 5-83 SPECIAL TOOLS 1. J-2185 Flaring Tool 6. J-22904 Dust Boot Installer 2. J-8000 Tubing Cutter 7. J-23518 Bleeder Adapter 3. J-8049 or J-22348 Spring Remover 8. J-23709 Combination Valve Pin Retainer 4. J21177 or J-22364 Drum/Shoe Gauge 9. J-24548 Dust Boot Installer 5.
Page 355 SECTION 6 ENGINE CONTENTS OF THIS SECTION Engine Tune-Up.............. 6-1 Engine Mechanical (V8)..........6-45 Theory of Operation............6-15 Diagnosis................6-67 Engine Mechanical (In Line)........6-20 Special Tools..............6-74 ENGINE TUNE-UP INDEX General Description............6-1 Choke Adjustment............6-7 Mechanical Checks and Adjustments......6-1 Instrument Check-Out..........
Page 356 6-2 ENGINE grasp the boot portion of the wire and apply only leak between the cylinders. Engine coolant and/ enough force to remove the boot. Do not pull on plug or oil in cylinders could result from this defect. wire. NOTE: If a weak cylinder cannot be located with the compression check, see “Cylinder Balance Test”...
Page 357 ENGINE points since particles will embed and cause arcing and rapid burning of points. Do not attempt to remove all roughness nor dress the point surfaces down smooth. Merely remove scale or dirt. • Clean cam lobe with cleaning solvent and rotate PORCELAIN cam lubricator wick 180°.
Page 358 6-4 ENGINE CARBON PATH CR ACK C ARB O N PATH ERODED TOWER C LE A N IN G & INSPECTION OF INSPECTION OF DISTRIBUTOR C L E A N IN G & INSPECTION OF OUTSIDE OF DISTRIBUTOR CAP INSIDE OF DISTRIBUTOR CAP C A P TOWERS REPLA CING DISTRIBUTOR ROTOR TIP...
Page 359 ENGINE PROPER LATERAL LATERAL ALIGNMENT MISALIGNMENT WEIGHT ROTOR ASSEMBLY •II ■ll "ll ll" CIRCUIT BREAKER CORRECT LATERAL MISALIGNMENT BY U PLATE ASSEMBLY L-| BENDING FIXED CONTACT SUPPORT NEVER BEND BREAKER LEVER PERMANENT LUBRICATION Fig. 6— Point Alignment RESERVOIR PRIMARY TERMINAL HOLD DO NOT SUCK TUBE...
Page 360 6-6 ENGINE Fig. 9— Manifold Heat Control Valve (L6) Fig. 8— Checking Fan Belt Tension described in “Additional Checks and Adjust ments” in this section, may be performed to detect internal or external leaks within the cooling system. SERVICE CRANKCASE VENTILATION (FIG.
Page 361 ENGINE as specified in Section 0. Perform necessary service designed, particularly, for these engines; therefore, they operations as specified in Section 6T. must not be interchanged with or replaced by a carburetor or distributor designed for different applications. CHOKE ADJUSTMENT Inspect choke valve, choke rod, choke coil and housing SERVICE EXHAUST GAS for proper alignment, bends and binding —...
Page 362 6-8 ENGINE Fig. 12— Crankcase Ventilation Valve Fig. 13— Crankcase Ventilation Filter CHECK-OUT INSTRUMENT distributor shaft, worn distributor shaft bushing or loose INSTRUMENT HOOK-UP breaker plate. Connect vacuum gauge, dwell meter, tachometer and timing light as recommended by the manufacturer of the CHECK AND ADJUST IGNITION equipment being used.
Page 363 ENGINE WINDOW "H EX” TYPE WRENCH ADJUSTING SCREW Fig. 14— Setting Point Dwell (Typical V8) C-P30 Series and all G30 Series (Except Sportvan Models). NOTE: Idle speed will increase as new engines loosen up during the first few hundred miles of operation. Idle speed should Fig.
Page 364 6-10 ENGINE NOTE: All carburetors are equipped with Reconnect “Fuel Tank” line to canister and reconnect distributor spark advance hose. idle mixture limiter caps (fig. 16). These caps permit limited adjustment (1/2 to 3/4 turn clockwise) to lean the idle mixture. Do not •...
Page 365 ENGINE 6-11 Before suspecting the carburetor as the cause of poor 8. Equally lean (turn in) mixture screws until the lower engine performance or rough idle, check ignition system specified idle speed is achieved (example 650/600). including distributor, set ignition timing, check PCV 9.
Page 366 6-12 ENGINE 9. Connect fuel tank vent hose and distributor vacuum advance hose. AND ADJUSTMENTS ADDITIONAL CHECKS each pair. A variation of more than 1 inch of CYLINDER BALANCE TEST vacuum or 40 rpm between pairs of cylinders being tested indicates that the cylinders are off balance. (FIG.
Page 367 ENGINE 6-13 Fig. 20— Cooling System Pressure Check more plugs adjacent in firing order, cross firing is occurring in distributor cap or between spark plug cables concerned. • If meter reads off scale to left, the coil polarity is Fig. 19— Testing Cranking Voltage reversed.
Page 368: Cooling System
6-14 ENGINE The following valves can be adjusted with engine in COOLING SYSTEM number six firing position: The following test may be performed with pressure Number two cylinder-Exhaust testing equipment available commercially for this purpose. This test provides an excellent means of Number three cylinder-Intake detecting internal or external leaks within the cooling Number four cylinder-Exhaust...
Page 369 ENGINE 6-15 hydraulic lifter plunger in the center of its travel. No other adjustment is required. With the engine in the number 1 firing position as determined above, the following valves may be adjusted. Exhaust - 1, 3, 4, 8 Intake - 1, 2, 5, 7 Crank the engine one revolution until the pointer “0”...
Page 370 6-16 ENGINE Fig. ID — Sectional View of Eight-Cylinder Engine completed by the time the piston is about half-way down Combustion so that maximum pressure will be developed in the The power delivered from the piston to the crankshaft is cylinder at the time the piston sends its greatest force to the result of a pressure increase in the gas mixture above the crankshaft.
Page 371 ENGINE 6-17 Fig. 2D— Sectional View of Six-Cylinder Engine high pressure within the cylinder to push the piston flow is slow. Valve timing allows for this lag in starting down smoothly during the power stroke. and stopping in the flow. In order to pack the maximum air-fuel mixture into the cylinder, each valve opens earlier and closes later than would be necessary if the Compression Ratio...
Page 372 6-18 ENGINE Fig. 4D— Piston Compression Stroke Fig. 3D— Piston Intake Stroke close, when the mixture is not moving fast enough to the cylinders most effectively. This is the speed at which take advantage of the time lag. At very high speeds, the the engine puts out its peak torque.
Page 373 ENGINE 6-19 Fig. 6D— Piston Exhaust Stroke Fig. 5D— Piston Power Stroke LIGHT DUTY TRUCK SERVICE MANUAL...
Page 374 6-20 ENGINE Fig. 8D— Valve System Components EN G IN E M E C H A N IC A L IN-LINE ENGINES INDEX Installation and Adjustment........6-27 General Description............6-21 Valve Lifters..............6-27 Component Replacement and Adjustment....6-21 Locating Noisy Lifters..........6-27 Engine Assembly............6-21 Removal................6-28 Removal (C, K and P Series).........
Page 375: General Description
ENGINE 6-21 Installation..............6-29 Measuring Lobe L ift..........6-33 Removal................6-34 Oil Seal (Rear M ain)..........6-30 Installation..............6-34 Replacement..............6-30 Timing Gears..............6-35 Torsional Damper............6-30 Replacement..............6-35 Removal................. 6-30 Flywheel................6-35 Installation..............6-31 Removal................6-35 Crankcase Front Cover..........6-32 Repair................
Page 376 6-22 ENGINE Six-Cylinder Fig. 1 L - • Raise engine and pull forward until disconnected • Remove engine mount bolts. from transmission. ON CS 10-20-30: • Continue to raise engine until removed from • Remove propeller shaft as outlined in Section 4. vehicle.
Page 377: Removal (G Series)
ENGINE 6-23 spring pressure is released. Remove all bolts, linkage and remove cross shaft as outlined in clutch disc and pressure plate assembly. Section 7. • Remove automatic transmission (if so equipped). 11. Remove propeller shaft as outlined in Section 4 - install plug in transmission extension.
Page 378: Installation (C, K And P Series)
6-24 ENGINE TOOL J-24680-2 Fig. 3L— Tool J-24680-2 Installed on Engine a. Remove clutch housing rear cover bolts. Fig. 4L— Lifting Device Installed to J-24680-2 b. Remove bolts attaching the clutch housing to engine block, then remove transmission and clutch housing as a unit. NOTE: Support the transmission as the last mounting bolt is removed and as it is being pulled away from the engine, to prevent...
Page 379: Installation (G Series)
ENGINE 6-25 2. Install engine in vehicle as follows: • Install the battery. ON ALL SERIES EXCEPT CS 10-20-30: • Install the floor panel and engine box as outlined in Section IB. • Install engine, and lower until transmission shaft lines up with clutch.
Page 380: Manifold Assembly
6-26 ENGINE 8. Separate manifolds by removing one bolt and two 6. Torque engine mount through bolts and crossmem nuts at center of assembly. ber frame bracket. 9. Disconnect exhaust gas recirculation valve hose. 7. Connect clutch linkage and/or transmission linkage and cross shaft as outlined in Section 7.
Page 381: Valve Mechanism
ENGINE 6-27 4. Connect crankcase ventilation hoses. Number five cylinder-Intake 5. Install air injection hose. Number six cylinder-Intake and Exhaust 4. Install distributor cap and spark plug wire Valve Mechanism assembly. Removal 5. Install rocker arm cover as outlined. 1. Remove rocker arm cover as outlined. 6.
Page 382: Removal
6-28 ENGINE a. Excessive varnish or carbon deposit causing Valve Stem Oil Seal and/or Valve Spring abnormal stickiness. Replacement b. Galling or “pickup” between plunger and bore 1. Remove rocker arm cover as outlined. of lifter body, usually caused by an abrasive 2.
Page 383: Installation
ENGINE 6-29 4. Remove fuel and vacuum line from retaining clip at water outlet then disconnect wires from temperature sending units. 5. Disconnect air injection hose at check valve. 6. Disconnect radiator upper hose at water outlet housing and battery ground strap at cylinder head. 7.
Page 384: Oil Seal (Rear Main)
6-30 ENGINE 4. Clean all sealant and foreign material from positioning flange over distributor lower bushing. Use no gasket. cylinder case bearing cap and crankshaft, using a non-abrasive cleaner. NOTE: Oil pump should slide easily into 5. Inspect components for nicks, scratches, burrs and place, if not, remove and reposition slot to machining defects at all sealing surfaces, case align with distributor tang.
Page 385: Installation
ENGINE 6-31 Fig. 13L— Crankshaft Oil Seal (Rear Main) Fig. 11L— Removing Oil Seal (Lower Half) Typical screw to remove damper (fig. 15L). Remove tool from damper. Installation The inertia weight section of the CAUTION: torsional damper is assembled to the hub with a rubber type material.
Page 386: Crankcase Front Cover
6-32 ENGINE Crankcase Front Cover Removal 1. Remove torsional damper as outlined. 2. Remove the two, oil pan-to-front cover attaching screws. 3. Remove the front cover-to-block attaching screws. 4. Pull the cover slightly forward only enough to permit cutting of oil pan front seal. 5.
Page 387: Oil Seal (Front Cover)
ENGINE 6-33 Oil Seal (Front Cover) Replacement With Cover Removed 1. With cover removed, pry seal out of cover from the front with a large screw driver being careful not to distort cover. 2. Install new seal so that open end of the seal is toward the inside of cover, and drive it into position with Tool J-23042 (fig.
Page 388: Removal
6-34 ENGINE J-23042 Fig. 23L— Installing Oil Seal (Cover Installed) Fig. 24L— Measuring Camshaft Lobe Lift (Typical) lobe. At this point, the push rod will be in its lowest position. 4. Set dial indicator on zero, then rotate the crankshaft slowly, or attach an auxiliary starter switch and “bump”...
Page 389: Timing Gears
ENGINE 6-35 a — — Fig. 26L— Checking Camshaft Gear Runout 4. If gear run out is excessive, the gear will have to be Fig. 27L— Checking Timing Gear Backlash removed and any burrs cleaned from the shaft or the gear will have to be replaced. 5.
Page 390: Repair
6-36 ENGINE RING CONVERTER GEAR BOLT AREA DEPRESSED WELDS TRANS. Fig. 30L— Flywheel Installation (Typical) crankshaft as necessary so dowels clear cylinder block. Remove flywheel and discard used dowel pins. Repair Only repair recommended at flywheel used with conventional clutch is replacement of starter gear in event gear is worn or otherwise damaged.
Page 391 ENGINE 6-37 points, lower the engine on the mounts and tighten the Rear Mount Replacement screws or nuts attaching the mount to the engine, frame, or bracket. C, K and Series 1. Raise and support vehicle. Rear M ount 2. Bend mount bolt french lock tabs away from bolt Raise the vehicle on a hoist.
Page 392 6-38 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 393 ENGINE 6-39 Fig. 33L— P Series Engine Front Mount LIGHT DUTY TRUCK SERVICE MANUAL...
Page 394 6 -40 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 395 ENGINE 6-41 LIGHT DUTY TRUCK SERVICE MANUAL...
Page 396 6-42 ENGINE LIGHT DUTY TRUCK SERVICE MANUAL...
Page 397 Fig. 37L— K Series Engine Front Mount...
Page 398 6 -4 4 ENGINE ^ FWD R EA R M O U N T FRO NT M O U N T Fig. 38L— G Series Engine Mounts LIGHT DUTY TRUCK SERVICE MANUAL...
Page 399 ENGINE 6-45 EN G IN E M E C H A N IC A L V-8 ENGINES INDEX General Description............6-45 Installation..............6-54 Component Replacement and Adjustment....Oil Pump................6-54 6-45 Removal................6-54 Engine Assembly............6-45 Removal................. 6-45 Installation..............6-54 Installation..............6-48 Oil Seal (Rear M ain)...........6-54 Intake M anifold............
Page 400 6-46 ENGINE 4. Disconnect wires at: ON KE 10-20 SERIES: • TCS Solenoid (if so equipped) • Raise engine and pull forward until disconnected from tranmission. • Starter Solenoid • Continue to raise engine until removed from • Delcotron vehicle. •...
Page 401 ENGINE 6-47 12. Mount engine in engine stand and remove lifting device and lifting adapter. G Series 1. Remove vehicle grille as outlined in Section 13. 2. Drain cooling system and disconnect heater outlet hose at radiator and inlet hose at heater core tube. 3.
Page 402 6-48 ENGINE f. Remove transmission-to-engine mounting bolts. aid of an assistant inside the vehicle, raise the engine while moving the engine assembly forward g. With the hoist attached, remove blocks from the and out of the vehicle (fig. 4V). engine only and slowly guide the engine away from the transmission.
Page 403 ENGINE 6 4 9 ON ALL SERIES: and transmission assembly and install flywheel • Remove the lifting device from engine lift to converter bolts. brackets. c. Install converter housing underpan and starter. 3. Connect transmission linkage (as required). d. Connect throttle valve linkage and vacuum 4.
Page 404 6-50 ENGINE 23. Install the engine access cover. Intake Manifold Removal 1. Drain radiator and remove air cleaner. 2. Disconnect: • Battery cables at battery. • Radiator upper hose and heater hose at manifold. • Water pump by-pass at water pump. •...
Page 405 ENGINE 6-51 4. On “Mark IV V8” engines, install spark plugs. 3. Adjust valves when lifter is on base circle of Torque plugs to specifications. camshaft lobe as follows: 5. On vehicles so equipped, install carburetor heater. a. Crank engine until mark on torsional damper lines up with center or “O”...
Page 406: Replacement (Front)
6-52 ENGINE 3. Install air line adapter Tool J-23590 to spark plug 1. Hard Rapping Noise—Usually caused by the plunger becoming tight in the bore of the lifter port and apply compressed air to hold the valves in body to such an extent that the return spring can no place.
Page 407 ENGINE 6-53 c. Compress the spring with Tool J-5892 and install sealer that will assure the proper coat is with the the valve locks then release the compressor tool, use of a paint roller. Too much sealer may hold the making sure the locks seat properly in the gasket away from the head or block.
Page 408: Replacement (Rear)
6-54 ENGINE Remove oil dip stick and tube. NOTE: Installed position of oil pump screen is with bottom edge parallel to oil pan rails. 3. On vehicles so equipped remove exhaust crossover pipe. 3. Install oil pan as outlined. 4. On vehicles equipped with automatic transmission remove converter housing under pan.
Page 409 ENGINE 6-55 13. Install the rear main bearing cap (with new seal) and torque to specifications. Torsional Damper Removal 1. Remove fan belt, fan and pulley. 2. Remove the radiator shroud assembly as outlined in Section 13. NOTE: If additional operations (such as camshaft removal) are not being performed, the radiator removal will not be necessary.
Page 410 6-56 ENGINE Crankcase Front Cover Removal Sm all V8 Engine 1. Remove torsional damper as outlined. 2. Remove water pump as outlined in Section 6K. 3. Remove crankcase front cover attaching screws and remove front cover and gasket, then discard gasket. M ark IV V8 Engine 1.
Page 411 ENGINE 6-57 seal with engine oil, and position cover over crankshaft end. 6. Loosely install the cover-to-block, upper attaching screws. 7. Tighten screws alternately and evenly while pressing downward on cover so that dowels in block are aligned with corresponding holes in cover. NOTE: Position cover so that dowels enter holes in cover without binding.
Page 412 6-58 ENGINE being careful not to damage the surface on the crankshaft. 2. Install new seal so that open end of seal is toward the inside of cover and drive it into position with Tool J-23042 on Small V8 engines or Tool J-22102 on Mark IV V8 engines (fig.
Page 413 ENGINE 6-59 Fig. 23V— Installing Crankshaft Sprocket 3. Rotate the crankshaft slowly in the direction of rotation until the lifter is on the heel of the cam lobe. At this point, the push rod will be in its lowest position. 4.
Page 414 6 60 ENGINE 4. Draw the camshaft sprocket onto camshaft using 7. If camshaft readings for all lobes are within the mounting bolts. Torque to specifications. specifications, remove dial indicator assembly. 5. Lubricate timing chain with engine oil. 8. Install and adjust valve mechanism as outlined. 6.
Page 415 ENGINE 6-61 mounts while raising engine. If an engine mount 5. Install retaining bolt and torque all bolts to exhibits: specifications. a. Hard rubber surface covered with heat check cracks; Rear Mount Replacement 1. Support engine weight to relieve rear mounts. b.
Page 416 6-62 ENGINE M A N U A L TRANSMISSION WITH PROPELLER SHAFT PARKING BRAKE ALL TURBO HYDRA-M ATIC 4 0 0 (EXCEPT MOBILE HOME CHASSIS) WITHOUT PROPELLER SHAFT PARKING BRAKE ALL M A N U A L TRANSMISSION ALL TURBO HYDRA-M ATIC 35 0 AUTOM ATIC TRANSMISSION ALL MOBILE HOME CHASSIS WITH PROPELLER SHAFT PARKING BRAKE...
Page 417 ENGINE 6-63 V IEW A CU IN MOTOR HOME CHASSIS 4 5 4 CU. IN. VIEW 4 5 4 CU V IEW ALL EXCEPT MOTOR HOME CHASSIS Fig. 31V— P Series Engine Front Mount LIGHT DUTY TRUCK SERVICE MANUAL...
Page 418 6-64 ENGINE Fig. 32V— G Series Engine Mounts LIGHT DUTY TRUCK SERVICE MANUAL...
Page 419 ENGINE 6-65 Fig. 33V— K Series Engine Mounts LIGHT DUTY TRUCK SERVICE MANUAL...
Page 420 6-66 ENGINE Fig. 34V— C Series Engine Mounts LIGHT DUTY TRUCK SERVICE MANUAL...
Page 421 ENGINE 6-67 DIAGNOSIS ENGINE FAILS TO START CAUSE a. Corroded or loose battery terminal connections and/or weak battery. b. Broken or loose ignition wires and/or faulty ignition switch. c. Excessive moisture on plugs, caps or ignition system. d. Damaged distributor rotor, cracked distributor cap and/or corroded distributor contact points.
Page 422 6-68 ENGINE i. Incorrect carburetor idle adjustment and/or dirty jets or plugged passages in carburetor. j. Foreign matter, such as dirt or water, in gas line or carburetor. k. Air leak at carburetor mounting gasket. 1. Choke inoperative. m. Faulty spark advance mechanism. n.
Page 423 ENGINE 6-69 h. Faulty coil or condenser. i. Distributor points burned, pitted, dirty, or incor rectly set. j. Distributor advance inoperative. k. Exhaust system restricted. 1. Leaks in carburetor mounting gasket or intake manifold. m. Incorrect valve lifter clearance. n. Burned, warped, or sticking valves. 0.
Page 424 6-70 ENGINE EXTERNAL ENGINE OIL LEAKAGE CAUSE a. Improperly seated or broken fuel pump gasket. b. Improperly seated or broken push rod cover gasket. c. Improperly seated or broken oil filter gasket. d. Broken or improperly seated oil pan gasket. e.
Page 425 ENGINE 6-71 NO OIL PRESSURE WHILE IDLING CAUSE a. Faulty oil gauge sending unit. b. Oil pump not functioning properly. (Regulator ball stuck in position by foreign material). c. Excessive clearance at main and connecting rod bearings. d. Loose camshaft bearings. e.
Page 426 6-72 ENGINE b. Improper fit of piston pin. c. Excessive accumulation of carbon in heads or piston tops. d. Connecting rods improperly aligned. e. Excessive clearance between rings and grooves. f. Rings broken. BROKEN PISTONS AND/OR RINGS CAUSE a. Undersize pistons installed. b.
Page 427 ENGINE 6-73 e. Faulty valve lifter plunger or push rod seat. f. Plungers excessively worn causing fast leakdown under pressure. g. Excessively worn camshaft lobes. h. Valve lifter oil feed holes plugged causing internal breakdown. i. Faulty valve lifter check ball. (Nicked, flat spot, or out of round).
Page 428 6 -7 4 ENGINE SPECIAL TOOLS J-4536 Engine L if t K it J-5715 (.003” ) Rocker A rm Stud Reamer J-1264 (0-200 F t. Lb.) Torque Wrench J-8058 (0-50 Ft. Lb.) J-6036 (.013” ) J-6880 Rocker A rm Stud Installer J-5853 (0-100 in lb.) J-8087...
Page 429 S E C T IO N 6K ENGINE COOLING INDEX Heater Core.............. 6K-9 General Description............. 6K-1 Fan Belt Adjustment..........6K-9 Theory of Operation............ 6K-2 Radiator Cap............... 6K-9 Maintenance and Adjustments........6K-7 Thermostat..............6K-9 Coolant Level............... 6K-7 Replacement............... 6K-9 Coolant System Checks..........6K-7 Periodic Maintenance..........
Page 430 6K-2 ENGINE COOLING Fig. 3— Water Pump— Typical V-8 THEORY OF OPERATION The engine cooling system is designed to maintain the coolant by-pass in the cylinder head and block. Coolant engine at its most efficient operating temperature at all circulation, after normal operating temperatures are engine speeds and all driving conditions.
Page 431 ENGINE COOLING 6K-3 Fig. 4— Engine Coolant Circulation (Six-Cylinder) combustion to the coolant and then to transfer heat in COMPONENTS the coolant to air flowing passed the radiator. Water Pump Radiators are of the cross-flow type (Fig. 5). The The cooling system water pump is of the centrifugal water flows horizontally from the input (left) tank vane impeller type.
Page 432 6K-4 ENGINE COOLING develops high pressure areas in front of the wipers, thus WARM WATER the fluid is forced back into the reservoir. But as the COLD RADIATOR TRANSMISSION FROM ENGINE FILL LEVEL OIL COOLER temperature rises the arm uncovers more of the large LINES opening and allows more of the silicone fluid to re-enter the working chamber.
Page 433 ENGINE COOLING 6K-5 Fig. 6— Automatic Fan Clutch ENGINE OVERHEATING A. Start with a cool engine to ensure complete fan clutch disengagement. Refer to Item b, paragraph B. If the fan and clutch assembly free-wheels with no drag (revolves over 5 times when spun by hand), the clutch should be replaced.
Page 434 6K-6 ENGINE COOLING between fan blades and thermometer sensor before starting engine. FLANGE PISTO N Position thermometer so that the thermometer sensor is centered in the space between the fan blades and radiator. This can be achieved by inserting the sensor through one of the existing holes in the fan shroud or fan guard, or by placing between the radiator and the shroud.
Page 435 ENGINE COOLING 6K-7 ment for -20°F. protection, coolant boiling point is less System Inhibitor and Sealer or equivalent. In addition, than the temperature indicating light setting. When Cooling System Inhibitor and Sealer should be added adding solution due to loss of coolant for any reason or every fall thereafter.
Page 436 6K-8 ENGINE COOLING 2. Remove thermostat and replace thermostat housing. Periodic Maintenance It is the owner’s responsibility to keep the freeze 3. Add the liquid portion (No. 1) of the cooling system protection at a level commensurate with the area in cleaner.
Page 437 ENGINE COOLING 6K-9 NOTE: Disconnect the heater hose and cap 3. Inspect thermostat valve to make sure it is in good connections at engine when reverse flushing condition. engine. 4. Place thermostat in a 33% glycol solution 25° above the temperature stamped on the thermostat valve. 2.
Page 438 6K-10 ENGINE COOLING Fig. 13 — Checking Run-Out Fig. 12— Securing Fan Blade movement. This represents the total radial run-out. Mark the point on the pulley at which the highest reading is obtained. 4. If the total indicator reading is less than .006 inch, the assembly is within specification.
Page 439 ENGINE COOLING 6K-11 vertical plane to prevent silicone fluid 1. Drain coolant from the radiator and break loose leakage. the fan pulley bolts. 4. Remove pump to cylinder block bolts and remove 2. Disconnect heater hose, radiator lower hose and by pump and old gasket from engine.
Page 440 6K-12 ENGINE COOLING disconnected hoses, loose pressure cap or use of low 2. Remove rocker arm covers and check for cracked boiling point antifreeze. These conditions prevent cylinder head. cooling system from maintaining proper pressure. 3. Remove cylinder heads and check gaskets. While heads are off, check for cracks in heads or block.
Page 441 ENGINE COOLING 6K-13 Fig. 16— Overheating Chart LIGHT DUTY TRUCK SERVICE MANUAL...
Page 442 6K -14 ENGINE COOLING Fig. 17— Coolant Loss Chart LIGHT DUTY TRUCK SERVICE MANUAL...
Page 443 SECTION 6M ENGINE FUEL NOTE: Also refer to "Emission Control Systems Booklet" and "Maintenance Sched ule Folder" for warranty and maintenance information. CONTENTS OF THIS SECTION Description..............6M-1 Service Operations............6.M-24 Theory of Operation..........6M-2 Diagnosis................ 6M-39 Maintenance and Adjustments........ 6M-15 Special Tools..............
Page 444 6M -2 ENGINE FUEL and vapor handling. As there are no external vents, the following: the carburetor is completely internally balanced. 1. All models are calibrated to assist in meeting emission requirements. 3. Plastic main well inserts in the main fuel wells provide improved fuel metering for the main 2.
Page 445 ENGINE FUEL 6M -3 Fuel Metering............6M-5 Float System............6M-9 Venturi Principle..........6M-6 Idle System.............. 6M-10 Distribution............. 6M-7 Main Metering System......... 6M-11 Fuel-Air Requirements.......... 6M-7 Power System............6M-12 Power vs. Economy..........6M-8 Pump System............6M-12 Cold Starts.............. 6M-9 Basic Carburetor Systems........6M-9 Choke System............
Page 446 6 M -4 ENGINE FUEL limits do not provide the two conditions most sought. atmosphere, the boiling point of the gasoline is lowered considerably. At this reduced pressure, latent heat The most desired ratios are a mixture that will produce absorbed from the many air particles surrounding each the most power per pound of gasoline and a mixture that fuel particle causes some vaporization, which is further...
Page 447 ENGINE FUEL 6M -5 conditions, so that the engine operation will neither be too lean for power requirements nor too rich for economy (Fig. 4), while still meeting prime requirements of low emissions. AIR MEASUREMENT Air flow through a pipe will create a pressure drop within the pipe proportional to the speed of the air.
Page 448 6 M -6 ENGINE FUEL sufficiently, at a given air flow, so that the resulting air- Further, if a means were provided to maintain the fluid fuel proportions result in a combustible mixture. level at a desired height in the U-tube, the amount of fluid flow would be proportional to the pressure For example, a carburetor with a 1 1 /2"...
Page 449 ENGINE FUEL 6M -7 venturis may be used for finer control of pressure drop receives a leaner mixture and 6 receives a richer mixture but at high speed they tend to restrict air flow to the than originally entered the manifold. engine.
Page 450 6 M -8 ENGINE FUEL carried along by the mixture of air and evaporated fuel. 11). Here, some slight enrichment is necessary due to the The intake manifold itself does not deliver exactly equal effect of exhaust-gas dilution in the cylinder and the air-fuel mixtures to all cylinders.
Page 451 ENGINE FUEL 6M -9 while maximum power should be available when the • Power System throttle is opened for acceleration or top speed (Fig. 13). • Pump System Through this point, we have covered the engine’s general • Choke System requirements insofar as the need for both a vaporized mixture and the proportions, or ratio, of the air-fuel vapor for efficient combustion.
Page 452 6 M -1 0 ENGINE FUEL systems in the carburetor, as the correct operation of all ports. At this point these ports act as air bleeds to further other systems depends on the proper level of fuel in the break up the mixture. The mixture flows past the mixture float bowl.
Page 453 ENGINE FUEL 6M -11 The point at which fuel flow starts from the main nozzle of the carburetor. It consists of a main jet, main well and is the transfer point (Fig. 16). This means that the main nozzle with air bleeds in it. The main jet is a very carburetor is passing from idle to main metering system.
Page 454 6M -1 2 ENGINE FUEL Under conditions of power, manifold vacuum will be low Power System which means vacuum will decrease on top of the piston allowing the spring to corce the power piston down, (Fig. 18) As discussed previously, richer fuel mixtures are needed opening the valve to increase the fuel flow to the main for high speed operation since maximum engine power nozzle.
Page 455 ENGINE FUEL 6 M -13 earlier design carburetors. It flows past the pump cup valve seats to prevent air from leaking into the discharge seal into the bottom of the pump well. The pump passage. When the throttle valves are opened, the plunger is the floating type of which the cup moves up connecting linkage forces the pump plunger downward.
Page 456 6 M -1 4 ENGINE FUEL warm-up, the corresponding drop in manifold vacuum located on the engine manifold. The coil is connected to the choke valve by a rod. The choke operation is and low air flow against the off-set choke valve, allows controlled by a combination of intake manifold vacuum, the thermostatic coil to momentarily close the choke, the off-set choke valve, thermostatic coil characteristics,...
Page 457 ENGINE FUEL 6M -15 MAINTENANCE AND ADJUSTMENTS NOTE: Also refer to the "Emission Control VACUUM ADVANCE SOLENOID, AND HOSES- Systems" Booklet for required maintenance The vacuum portion of this valve should be checked, and warranty information. with the transmission in neutral, by using a vacuum gauge attached to the valve (or solenoid) distributor Timing Points (Dwell), Idle Speed - These adjustments connector.
Page 458 6 M -1 6 ENGINE FUEL G10, 20 All 3. Disconnect fuel tank vent hose from vapor canister, G30 Sportvan (All Light Duty and on Heavy Duty if equipped) and disconnect and plug distributor vacuum hose at Heavy Duty Vehicles: vacuum advance unit.
Page 459 ENGINE FUEL 6 M -17 IDLE MIXTURE ADJUSTMENT SPECIFICATIONS LIGHT DUTY EMISSION VEHICLES Transmi ss ion GM 102 250 cu. in. - Federal M a n u a 1 Automat i c AIR-EGR CCS-EGR Exhaust Emission Control System Timing (°BTC @ RPM) °...
Page 460 6 M -1 8 ENGINE FUEL HEAVY DUTY EMISSION VEHICLES LEAN DROP FAMILY ENGINE (ClD) IDLE SPEED (RPM) TIMING (°BTC) SETTINGS (RPM) GM111 700/600 700/600 GM112 350/4bbl 750/600 GM1 13 800/700 G M 1 15 ALTERNATE PROCEDURE IDLE MIXTURE ADJUSTMENT disconnect and plug distributor vacuum hose at TO BE USED ONLY IF RELIABLE CO vacuum advance unit.
Page 461 ENGINE FUEL 6M -19 HEAVY DUTY EMISSION VEHICLES If Over Max. Max. Acceptable A cceptable Level CO Level Reset to {% or Less) @ Level F a m i i y GM 111 (250 c u in.) GM 1 12 (292 c u in.) GM 113 (350 c u in.
Page 462 6 M -2 0 ENGINE FUEL RO D IN END OF SLOT HOLD DOWN O N CHOKE VALVE G AUG E BETW EEN CHO KE VALVE AND AIR HORN WALL BEND RO D TO ADJUST CAM FOLLOW ER MUST B E HELD FIRMLY ON SECO ND STEP OF FAST IDLE CAM (4MV)
Page 463 ENGINE FUEL 6M -21 4. With the choke valve held in this position, place specified gauge between the lower edge of the choke in place. The end of vacuum break rod should also valve and air horn wall. be in outer end of slot in vacuum break diaphragm 5.
Page 464 6 M -2 2 ENGINE FUEL ( 7 ) GAUGE BETWEEN UPPER EDGE OF CHOKE VALVE AND AIR HORN CASTING ( T ) THROTTLE VALVES WIDE OPEN BEND TANG TO ADJUST AIR VALVE DASHPOT ADJUSTMENT 4MV Fig. llC -Choke Unloader (2GV) (Fig.
Page 465 ENGINE FUEL 6M -23 A IR VALVE CHOKE VALVE CO M PLETELY CLOSED COMPLETELY CLOSEDf BEND ROD HERE TO O B TA IN SP EC IFIE D CLEAR AN CE BETWEEN ROD A N D END OF SLOT IN LEVER D IA P H R A G M EATED O U T SID E...
Page 466 6 M -2 4 ENGINE FUEL SERVICE OPERATIONS (INCLUDING ADDITIONAL EXTERNAL SETTINGS AND ADJUSTMENTS) INDEX 6M-37 Fuel Pumps... Carburetor Removal...........6M-24 Special Tools 6M-64 Accelerators and Choke Controls......6M-27 Air Cleaners..............6M-30 ALL CARBURETORS TORQUE TO 14 FT. LBS. H 4 NOTE Insulator must be assembled with notch REMOVAL (Figs.
Page 467 ENGINE FUEL 6M -2 5 Fig. K4-Fuel Filter (Paper-Type) (Typical) 8. Remove carburetor attaching nut and/or bolts, gasket or insulator and remove carburetor. TEST BEFORE INSTALLATION It is good shop practice to fill the carburetor bowl before installing the carburetor. This reduces the strain on the starting motor and battery and reduces the possibility of backfiring while attempting to start the engine.
Page 468 6 M -2 6 ENGINE FUEL solenoid adjustment and idle mixture adjustment; WITH ROCHESTER also, "Additional external settings CARBURETORS adjustments".) Remove the choke coil shield by prying with a screw driver on the small tangs at base of shield, then lift shield carefully over rod.
Page 469 ENGINE FUEL 6M -27 a. Turn the solenoid clockwise to increase RPM, a. Disconnect electrical connection at the end of counterclockwise to decrease RPM. Refer to the idle stop solenoid. Specifications, Section 6M, under "Other Ad b. Adjust carburetors low idle (Adjustment screw justments", column No.
Page 470 6M -2 8 ENGINE FUEL SEALER ICable is not to be kinked CAUTION or damaged in any way during assembly operation (e.g. engine i n s t a l l a t i o n ) . ENGINE SUPPORT _______W ith In n e r S p rin g in s id e o f ENGINE O uter S p rin g , anchor both S prin gs .SPRING INNER...
Page 471 ENGINE FUEL 6M -2 9 I SI ip accelerator control cable NOTE ROD ASSEMBLY THROTTLE CONTROL thru s lo t in Rod. In sta ll retainer, DASH & TOE being sure i t is seated. PANEL 1 CAUTlOW~|Care must be used in pressing the retainer into hole in Rod to assure cable is not kinked or damaged in any way.
Page 472 6 M -3 0 ENGINE FUEL RADIO BRACKET INSTRUMENT PANEL REINFORCEMENT TORQUE AT 7 FT. LBS TORQUE AT 20 IN. LBS. 030 Min clearance between I Lever and ac ce le rato r pedal rod at CABLE & 'close d t h r o t t le , (hot i d l e p ositio n BRACKET V / with choke o f f ) , to allow engine to ASSEMBLY...
Page 473 ENGINE FUEL 6M -31 AIR CLEANER VALVE/ TE E ASSEMBLY 50° ±2° ASM /CLAMP ' £ ROCKER ' COVER CLAMP HOSE VALVE BOTTOM ASSEMBLY n grommet HOSE ARRESTOR - —r f ASSEMBLY VVIEW A Fig. 2A-Engine Ventilation, (L-6) ELEMENT COVER The polywrap element air cleaner consists of a paper element in addition to a polyurethane band.
Page 474 6 M -3 2 ENGINE FUEL W IN G N U T ---------- CLEANER TORQUE AT 2 0 IN. LBS CLEANER CHAMFER END RETAINER ^ GASKET STUD TORQUE AT (17 IN. LBS.) EXTENSION GASKET TORQUE AT 25 IN. LBS. SUPPORT STUD OIL LEVEL GAGE TUBE...
Page 475 W IN G NUT TORQUE AT 20 IN. LBS. AIR CLEANER NOTE! GASKET I Colored adhesive surface to carburetor. STUD TORQUE AT 20 IN. LBS. TORQUE AT 75 IN. LBS. TORQUE AT 7 5 IN. LBS. TORQUE AT CARBURETOR 75 IN. LBS. ASSEMBLY TORQUE AT 75 IN.
Page 476 6 M -3 4 ENGINE FUEL A IR TO AIR 17 IN. LBS. TORQUE CLEANER CLEANER 'CHAMFER END CARBURETOR EXTENSION VIEW B SUPPORT STUD V G E 10-15 "GASKET OIL LEVEL AIR CLEANER GAGE TUBE EXTENSION STUD VIEW A GASKET Position red n o t e i TU BE-'-'...
Page 477 ENGINE FUEL 6M -35 AIR CLEANER STUD OIL GAGE TUBE SUPPORT — PSI 00-150(35) EXTENSION COIL ASM UPC 6Y NOTE Position red adhesive surface down when installing gaskets. AIR CLEANER PS100-150^ P S MODELS Fig. 7A~Air Cleaner and Heat Stove, P Series W ING NUT TORQUE AT 20 LBS IN POLYWRAP A IR V...
Page 478 6 M -3 6 ENGINE FUEL AIR BLEED VALVE VIEW B-UNDERHOOD TEMPERATURE CLOSED VIEW A— ENGINE OFF BELOW 85°F DIAPHRAGM SPRING TEMP. SENSING DIAPHRAGM SPRING SPRING VACUUM CHAMBER SNORKEL TUBE VACUUM CHAMBER SNORKEL TUBE DIAPHRAGM —i HOT AIR PIPE CONTROL DAMPER ASSM. 1 | f CONTROL DAMPER ASSM.
Page 479 ENGINE FUEL 6 M -37 Fig. 13A-Checking Vacuum Diaphragm Fig. 15A-Removing Sensor Unit INSTALL REPLACEMENT RETAINING STRAP SENSOR ASSM. IN SAME POSITION AS ORIGINAL ASSM. Fig. 14A-Vacuum Diaphragm Replacement FUEL PUMP INDEX General Description............Test................6M-37 6M-38 Service Procedures............Removal................. 6M-37 6M-39 Inspection..............
Page 480 6 M -3 8 ENGINE FUEL Before removing pump disconnect fuel pipe at gas tank and outlet pipe and blow th ough them with an air hose to make sure they are clear. Reconnect pipes and retest while cranking engine. Whenever the engine is cranked CAUTION: remotely at the starter, with a special jumper...
Page 481 ENGINE FUEL 6M -3 9 certain that pump is operating within specified limits as follows: a. Attach a fuel pump pressure test gauge to disconnect end of pipe. b. Run engine at approximately 450-1,000 rom (on gasoline in carburetor bowl) and note reading on pressure gauge.
Page 482 6 M -4 0 ENGINE FUEL ROCHESTER CARBURETOR D I A G N O S I S M O D ELS M , M V - 2 G , 2 G V — 4M , 4 M V . NOTE: These problems can be caused by many things other than carburetor.
Page 483 ENGINE FUEL 6M -41 ROCHESTER CARBURETO R DIAG NO SIS MODELS M, MV P O S S IB L E C A U S E C O R R E C T I V E A C T IO N Carburetor flo o d ing (continued) 3.
Page 484 6 M -4 2 ENGINE FUEL ROCHESTER CARBURETO R DIAG NO SIS MODELS M, M V C O R R E C T I V E A C T IO N P O S S IB L E C A U S E Carburetor flo o d ing (continued) NOTE: A solid flo a t can be checked fo r fuel absorption...
Page 485 ENGINE FUEL 6M -4 3 MODELS M, M V ROCHESTER CARBURETO R DIAG NO SIS P O S S IB L E C A U S E C O R R E C T I V E A C T IO N D irt in pum p passages or pum p jet.
Page 486 6 M -4 4 ENGINE FUEL ROCHESTER CARBU RETO R D IAG NO SIS MODELS M, M V Problem : e n g i n e r u n s u n e v e n o r s u r g e s C O R R E C TIVE A C TIO N POSSIBLE CAUSE Check all hoses and fuel lines fo r bends, kinks or leaks.
Page 487 ENGINE FUEL 6M -4 5 ROCHESTER CARBURETO R DIAG NO SIS MODELS M, M V P O S S IB L E C A U S E C O R R E C T I V E A C T IO N Run engine at RPM where nozzle is feeding fuel.
Page 488 6 M -4 6 ENGINE FUEL SERVICE PROCEDURES MODELS M, M V (2 ) WITH GASKET REMOVED, GAUGE FROM TOP OF CASTING TO TOP OF INDEX POINT A T TOE OF FLO AT GAUGE BETWEEN LOWER EDGE OF CHOKE V A L V E AND ' INSIDE A IR HORN W ALL HOLD DOWN ON CHOKE...
Page 489: Service Procedures
ENGINE FUEL 6M-47 SERVICE PROCEDURES - MODELS M, MV © © HOLD CHOKE V A L V E TOP EDGE OF ROD © WIDE OPEN SHOULD BE EVEN WITH GAUGE BETWEEN LOWER BOTTOM OF HOLE EDGE OF CHOKE V A LV E <D AND A IR HORN W ALL PUSH DOWN...
Page 490 6M -48 ENGINE FUEL ROCHESTER CARBURETOR D IA G N O S IS MODELS 2G, 2 G V - TWO BARREL ENGINE CRANKS (TURN OVER) WILL NOT START OR STARTS HARD WHEN COLD POSSIBLE CAUSE C O R R E C T IV E A C T IO N Improper starting procedure used.
Page 491 EN G IN E FUEL 6M-49 ROCHESTER CARBURETOR DIAGNOSIS - MODELS 2G, 2GV - TWO BARREL Problem: e n g in e s t a r t s a n d s t a l l s P O S S IB L E C A U S E C O R R E C T I V E A C T IO N Engine does not have enough fast idle speed when cold.

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