JLG 450A Service And Maintenance Manual
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JLG 450A Service And Maintenance Manual

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Service and Maintenance Manual
Model
450A
450AJ
3120869
February 16, 2000

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  • Page 1 Service and Maintenance Manual Model 450A 450AJ 3120869 February 16, 2000...
  • Page 2 We sell worldwide for the brands: Genie, Terex, JLG, MultiQuip, Mikasa, Essick, Whiteman, Mayco, Toro Stone, Diamond Products, Generac Magnum, Airman, Haulotte, Barreto,...

  • Page 3: Bhydraulic System Safety

    Relieve system pressure by cycling the applicable control several times with the engine stopped and ignition on, to direct any line pressure back into the reservoir. Pressure feed lines to system components can then be discon- nected with minimal fluid loss. 3120869 – JLG Lift –...
  • Page 4 August 5, 1999 - Revised 2-54 thru 2-57 - Updated 10-12-99 2-59 - Updated 10-12-99 1-4 thru 1-6 - Updated 11-1-99 2-26 - Updated 11-1-99 1-2 and 1-3 - Updated 2-16-00 2-59 thru 2-62 - Updated 2-16-00 – JLG Lift – 3120869...

  • Page 5: Table Of Contents

    Preventive Maintenance and Inspection Schedule........2-63 3120869 – JLG Lift –...
  • Page 6 Valve Location - Chassis ............2-58 – JLG Lift –...
  • Page 7 Electrical System - Troubleshooting ..........3-18 3120869 – JLG Lift –...
  • Page 8 TABLE OF CONTENTS This Page Left Blank Intentionally. – JLG Lift – 3120869...

  • Page 9: Section 1. Specifications

    NOTE: Torque hubs should be one half full of lubricant. Maximum Capacity - 230 kg Engine Crankcase (Ford LRG425) - 4.5 L Maximum Tire Load (450A) - 3230 kg Engine Crankcase (Deutz F3M1011F) - 6 L Maximum Tire Load (450AJ) - 3357 kg Overall Width - 1.98 m...

  • Page 10: Torque Requirements

    ISO Viscosity Grade mends the use of Mobil DTE11. Specific Gravity .910 Aside from JLG recommendations, it is not advisable to Pour Point, Max -44° F (-44° C) mix oils of different brands or types, as they may not con- Flash Point, Min.

  • Page 11: Pressure Settings - Psi (Bar)

    Rod Dia. 4 ft. Platform Oscillation 2.5 in. 4.125 in. 1.75 in. Extend-A-Reach (63.5 mm) (104.8 mm) (44.45 mm) Upper Boom (450A) Lower Lift 4.5 in. 21.5 in. 2.5 in. Upper Boom (450AJ) 1250 (114.3 mm) (546.1 mm) (63.5 mm)
  • Page 12 SECTION 1 - SPECIFICATIONS Figure 1-1. Lubrication Diagram Updated 11-1-99 – JLG Lift – 3120869...
  • Page 13 Adjust final oil level by mark on dipstick. Fuel Filter - Ford Replaceable Element Fuel Filter - Deutz Replaceable Element Replaceable Fuel Filter - Isuzu Element Air Filter - Ford Replaceable Or as indicated by condition indicator Element Updated 11-1-99 3120869 – JLG Lift –...
  • Page 14 Start engine, allow the engine to run until the thermostat opens (approximately 105 degrees C) cooler will fill up within minutes; shut down and wait for approximately two minutes. Check oil level, fill oil to max marking on dipstick. Updated 11-1-99 – JLG Lift – 3120869...

  • Page 15: Function Speeds (In Seconds)

    Tele Out - 14-30 Swing - 85-110 Rotate (Left & Right) - 16-25 E-A-R Up - 9-24 E-A-R Down - 12-24 xxxxxxx SERIAL NUMBER SERIAL NUMBER STAMPED ON FRAME PLATE Figure 1-2. Serial Number Locations 3120869 – JLG Lift –...
  • Page 16 SECTION 1 - SPECIFICATIONS – JLG Lift – 3120869...
  • Page 17 We sell worldwide for the brands: Genie, Terex, JLG, MultiQuip, Mikasa, Essick, Whiteman, Mayco, Toro Stone, Diamond Products, Generac Magnum, Airman, Haulotte, Barreto,...

  • Page 18: Section 2. Procedures

    2. At any time when air, fuel, or oil lines are discon- nected, clear adjacent areas as well as the openings and fittings themselves. As soon as a line or compo- 3120869 – JLG Lift –...

  • Page 19: Lubrication And Information

    Hydraulic system filters should checked, cleaned, and/or replaced as necessary, at the speci- fied intervals required in the Lubrication Chart in Section 1. Always examine filters for evidence of metal particles. – JLG Lift – 3120869...

  • Page 20: Cylinders - Theory Of Operation

    1. Refer to Section 1 for recommendations for viscosity key designations appearing in the Lubrication Chart. ranges. 2. JLG recommends Mobilfluid 424 hydraulic oil, which has an SAE viscosity of 10W-30 and a viscosity 2.4 CYLINDERS - THEORY OF OPERATION index of 152.

  • Page 21: Valves - Theory Of Operation

    BOOM PIVOT LEVEL LINK PIVOT Figure 2-1. Location of Components - Boom Removal – JLG Lift – 3120869...
  • Page 22 Using a suitable brass drift and ham- POWERTRACK. mer, remove pin from the turntable. FLY BOOM RETAINING RING RETAINING RING BASE BOOM TELESCOPE CYLINDER Figure 2-2. Location of Components - Removal of Telescope Cylinder 3120869 – JLG Lift –...
  • Page 23 Insert pin and secure with retaining ring. bushings as necessary. 12. Align bolt holes at aft end of base boom section with 5. Inspect wear pads for wear. telescope cylinder port block. Secure telescope cyl- inder with hardware. – JLG Lift – 3120869...

  • Page 24: Drift Test

    9. Shut down machine systems and check for leakage. leakage by cylinder piston. 7. Leave boom elevated in test position for approxi- mately one hour. BEFORE LOWERING BOOM, ENSURE THAT AREAS BELOW BOOM AND PLATFORM ARE CLEAR OF ALL PERSONNEL AND OBSTRUCTIONS. 3120869 – JLG Lift –...

  • Page 25: Cylinder Checking Procedure

    If boom has lowered and oil is leaking from the counterbalance valve, the valve is either improperly adjusted or defective and requires replacement. – JLG Lift – 3120869...

  • Page 26: Cylinder Repair

    6. If used, remove lifting device from upright or remove prop from below main boom, activate hydraulic sys- tem and run cylinder through one complete cycle to check for leaks. 3120869 – JLG Lift –...
  • Page 27 SECTION 2 - PROCEDURES Figure 2-4. Boom Prop Configuration 2-10 – JLG Lift – 3120869...
  • Page 28 Figure 2-6. Capscrew Removal on the piston. NOTE: Steps 6 applies only to the lower lift and telescope cylinders. 6. Using a spanner wrench, loosen the end cap or head retainer, and remove from cylinder barrel. 3120869 – JLG Lift – 2-11...
  • Page 29 6. Inspect piston surface for damage and scoring and 14. Inspect travel limiting collar or spacer for burrs and for distortion. Dress piston surface or replace piston sharp edges. If necessary, dress inside diameter as necessary. surface with Scotch Brite or equivalent. 2-12 – JLG Lift – 3120869...
  • Page 30 Replace as necessary. Assembly NOTE: Prior to cylinder assembly, ensure that the proper cylinder seal kit is used. See your JLG Parts Manual. Apply a light film of hydraulic oil to all components prior to assembly. 1. A special tool is used to install a new rod seal into the applicable cylinder head gland groove.
  • Page 31 11. Assemble the tapered bushing loosely into the pis- alignment with each other. ton and insert JLG capscrews (not vendor cap- screws) through the drilled holes in the bushing and into the tapped holes in the piston.
  • Page 32 17. Position the cylinder barrel in a suitable holding fix- ture. EXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THE CYLINDER ROD, HEAD, AND PISTON. AVOID PULLING THE ROD OFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE PISTON AND CYLINDER BARREL SURFACES. 3120869 – JLG Lift – 2-15...

  • Page 33: Mid And Lower Lift Cylinder Bleeding Procedure

    THE MACHINE, EXTREME CARE SHOULD BE USED TO INSURE THAT THE OUTER END OF THE ROD IS SUPPORTED. USE EITHER A TRAVELING OVERHEAD HOIST, FORK-LIFT, OR OTHER MEANS TO SUPPORT THE OVERHANGING WEIGHT OF THE EXTENDING ROD. 2-16 – JLG Lift – 3120869...
  • Page 34 6. Loosen the four metric hex head bolts. 7. Remove pump from vise and place on clean work bench, remove the four hex head bolts and spacers if applicable. 3120869 – JLG Lift – 2-17...
  • Page 35 16. Remove the dowel pins from the gear housing. Do not lose pins. 13. Remove the front bearing block. 17. Remove seals from both bearing blocks and dis- card. 2-18 – JLG Lift – 3120869...
  • Page 36 "wipe" on the inside surface on the intake side. shafts at the bearing points and seal area for rough There should not be excessive wear or deep surfaces and excessive wear. scratches and gouges. 3120869 – JLG Lift – 2-19...
  • Page 37 E-seal there is a notch make sure that these notches line up so the backup ring will set flush with the E-seal). The backup ring in the W1500 pump is symmetrical. 2-20 – JLG Lift – 3120869...
  • Page 38 10. Pick up the rear bearing block, with seal side up and with open end of the E-seal facing the intake side of the pump, place over the drive and idler gear shafts. 3120869 – JLG Lift – 2-21...
  • Page 39 17. Place mounting flange of the pump back in the pro- tected jawed vise and alternately torque the bolts to the torque specifications in the torque chart. All torque figures are for "dry torque” bolts. 18. Remove pump from vise. 2-22 – JLG Lift – 3120869...

  • Page 40: Swing Bearing

    NOTE: This check is designed to replace the existing bear- insert the 0.0015" feeler gauge between the bolt ing bolt torque checks on JLG Lifts in service. This head and hardened washer at the arrow indicated check must be performed after the first 50 hours of position.
  • Page 41 SECTION 2 - PROCEDURES REMOTE Figure 2-18. Swing Bearing Installation 2-24 – JLG Lift – 3120869...
  • Page 42 2. Line up high spot (blue) of bearing with center tooth of worm gear. Set backlash to 0.20 - 0.25 mm (0.008 - 0.010 inch). Tighten capscrews as shown in Figure 2-21., Swing Bearing Torquing Sequence. 3120869 – JLG Lift – 2-25...
  • Page 43 14. Route hydraulic lines through center of turntable and frame and connect as tagged prior to removal. JLG INDUSTRIES RECOMMENDS THAT ALL REMOVED GRADE 8 BEARING NUTS AND BOLTS BE DISCARDED AND REPLACED 15. Using all applicable safety precautions, activate the WITH NEW NUTS AND BOLTS.

  • Page 44: Worm Gear

    2.13 WORM GEAR Fig 2 Adjusting End Play. Checking Worm Gear End Play NOTE: JLG Industries requires that a annual inspection be performed on the worm gear end play. 1. Using a dial indicator, measure end play of worm Parts Required gear, by applying side to side movement by hand to 7016682 Shim Kit Includes;...

  • Page 45: Extend-A-Reach

    Use a suitable lifting device and remove the extend a reach. TOP TUBE GUARD E.A.R. CYLINDER PIVOT SHAFT ROTATE CYLINDER BOTTOM TUBE CHECK VALVE PLATFORM SUPPORT Figure 2-23. Extend-A-Reach 2-28 – JLG Lift – 3120869...

  • Page 46: Torque Hub (Prior To S/N 39594)

    (10) out of the card the roll pin (9). carrier (8). 4. Remove the planet gear (11) and the flat tanged washers (12) from the carrier. 3120869 – JLG Lift – 2-29...
  • Page 47 NOTE: The outboard bearing and seal will have to be removed from the spindle. You will have to scrap out the seal and bearing to remove them from the spin- dle. 6. Remove the inboard bearing (23) from the inboard cup (24). 2-30 – JLG Lift – 3120869...
  • Page 48 SECTION 2 - PROCEDURES Figure 2-27. Torque Hub (Prior to S/N 39594) - Exploded View 3120869 – JLG Lift – 2-31...
  • Page 49 SECTION 2 - PROCEDURES Figure 2-28. Torque Hub (Prior to S/N 39594) - Cutaway View 2-32 – JLG Lift – 3120869...
  • Page 50 3. With the unit still in the fixture, press in the outboard 9. Install the sun gear (28) into the cluster gears (11). cup (24). Be sure that the punch marks remain in their correct location. 4. Place outboard bearing (23) into the outboard cup. 3120869 – JLG Lift – 2-33...

  • Page 51: Torque Hub (S/N 39594 To Present)

    22. Remove o-ring (5) from the counterbore around the hub (1G). edge of cover (6A). Discard the o-ring. NOTE: If o-ring is not in the cover counterbore, it is in the ring gear counterbore. Remove it from the hub and discard it. 2-34 – JLG Lift – 3120869...
  • Page 52 SECTION 2 - PROCEDURES Figure 2-29. Torque Hub (S/N 39594 to Present) - Cutaway View 3120869 – JLG Lift – 2-35...
  • Page 53 6. Pry o-ring (6F) out of the groove inside cover cap (6B). Discard the o-ring. 7. Remove o-ring (6G) from the flange of cover cap (6B). Discard the o-ring. 8. Remove pipe plug (6H) from cover (6A). 2-36 – JLG Lift – 3120869...
  • Page 54 7. Following the cluster gear, place one more thrust housing (3A). washer (3B) onto planet shaft (3E) through the opposite planet shaft hole in carrier housing (3A). 3120869 – JLG Lift – 2-37...
  • Page 55 Assembly of the Cover 1. Using the disconnect rod, push o-ring (6F) into the groove inside the cover cap (6B). 2-38 – JLG Lift – 3120869...
  • Page 56 (6D) onto the cover cap (6B), aligning the pipe plug and tighten it into the pipe plug hole in the cover hole in the disconnect cap over the pipe plug hole in (6A). the cover cap. 3120869 – JLG Lift – 2-39...
  • Page 57 3. Apply a light coat of "Never-Seize" to two pipe plugs (1J) and tighten them into the two pipe plug holes in the side of the hub (1G). NOTE: Make sure the cup sits square with the counterbore before pressing. 2-40 – JLG Lift – 3120869...
  • Page 58 NOTE: O-ring may be stretched or pinched together to make it fit the counterbore exactly. 9. Place spacer (1H) onto spindle (1A) in hub (1G). NOTE: Make sure the retaining ring is securely seated in the groove. 3120869 – JLG Lift – 2-41...
  • Page 59 WEAR SAFETY GLASSES DURING THIS STEP, AND BE AWARE THAT SPRING AND SPACERS, COMPRESSED BY RETAINING RING , MAY P OP SUDDENLY OFF SHAFT I F T HE RING I S RELEASED BEFORE IT IS PROPERLY IN PLACE. 2-42 – JLG Lift – 3120869...
  • Page 60 9. With large splined end down, place input shaft sub- Locate the punch marks on the face of each cluster assembly (7) into spindle (1A). gear (3F) and position them at 12 o’clock. Figure 2-30. Cluster Gear Punch Marks 3120869 – JLG Lift – 2-43...
  • Page 61 16. Set the cover (6A) on table, interior side up. Grease o-ring (5) and place it into the counterbore around the edge of cover (6A). NOTE: The o-ring may be stretched or pinched together to make it fit the counterbore exactly. 2-44 – JLG Lift – 3120869...

  • Page 62: Drive Brake (Ausco)

    21. Place the 12 bolts into the remaining bolt holes in cover (6) and tighten. 22. Torque the shoulder bolts (13) 25 to 34 Nm (18 to 25 ft.lbs.). Torque bolts (12) 25 to 34 Nm (18 to 25 ft.lbs.). 3120869 – JLG Lift – 2-45...
  • Page 63 Retaining Ring 14. Stationary Disc 23. Washer Seal 15. Piston 24. Bolt Spring Retainer 16. Back-up Ring 25. Gasket Small Compression Spring 17. O-ring Large Compression Spring 18. Back-up Ring Figure 2-31. Drive Brake (Ausco) 2-46 – JLG Lift – 3120869...
  • Page 64 Teflon back-up rings. Visually align the center of the cutouts in the piston with the torque pin (3) holes in the power plate (21). 3120869 – JLG Lift – 2-47...

  • Page 65: Boom Limit Switches

    3. Adjust the proximity switch so there is 0.030 inch (0.8 mm) clearance between the end of the switch and the contact plate or until the light comes on. 2-48 – JLG Lift – 3120869...

  • Page 66: Throttle Checks And Adjustments - Deutz Engine

    Procedure NOTE: Never run fuel tank dry. Diesel engines cannot be restarted after running out of fuel until fuel system has been air-vented or bled of air. See Deutz Instruc- tion Manual for procedure. 3120869 – JLG Lift – 2-49...
  • Page 67 4. Reconnect linkage and reset each potentiometer for 3. Check wiring for any damage and correct. correct operation. 4. Disconnect engine harness and actuator connnec- 5. If failure continues to occur, replace unit. tions. 5. If problem reoccurs return unit. 2-50 – JLG Lift – 3120869...

  • Page 68: Drive And Steer Controller

    2 seconds is measured between the Threshold and Hi or to off time of the PWM signal is called the Duty Cycle, if it LO range setting. is on for 80% we call that an 80% duty cycle. 3120869 – JLG Lift – 2-51...
  • Page 69 Have the machine fully operational in an area where obstacles are not present. Use your meter to monitor the current output, and record that number once you have set the function to the proper speed. 2-52 – JLG Lift – 3120869...

  • Page 70: Lift And Swing Controller

    The percentage of on time to off time of the tion in both directions. PWM signal is called the Duty Cycle, if it is on for 80% we call that an 80% duty cycle. 3120869 – JLG Lift – 2-53...
  • Page 71 5. With the function speed switch turned to the fully CW position, activate the Platform Rotate switch and adjust Lo Range to 800 mA. 6. Set Ramp about 10 turns CW from the fully CCW position. Updated 10-12-99 2-54 – JLG Lift – 3120869...

  • Page 72: Tilt Alarm Switch

    1. Install the pressure gauge at port G2 on the Main Valve. 2. Activate Tower Lift Down and hold. 3. The pressure gauge should read 3200 +200, -50 psi (220 +14, -3.5 bar). Figure 2-38. Tilt Switch Adjustment Updated 10-12-99 3120869 – JLG Lift – 2-55...
  • Page 73 SECTION 2 - PROCEDURES Figure 2-39. Main Valve (Proportional Controls) - Sheet 1 Updated 10-12-99 2-56 – JLG Lift – 3120869...
  • Page 74 SECTION 2 - PROCEDURES Figure 2-40. Main Valve (Proportional Controls) - Sheet 2 Updated 10-12-99 3120869 – JLG Lift – 2-57...
  • Page 75 SECTION 2 - PROCEDURES REAR FLOW DIVIDER HIGH SPEED VALVE BYPASS VALVE FRONT FLOW DIVIDER TWO WHEEL/FOUR WHEEL VALVE Figure 2-41. Valve Location - Chassis 2-58 – JLG Lift – 3120869...

  • Page 76: Hydraulic Component Start-Up Procedures And Recommendations

    Make certain that all system com- ponents (reservoir, hoses, valves, fittings, heat exchanger, etc.) are clean prior to filling with fluid. Updated 2-16-00 3120869 – JLG Lift – 2-59...
  • Page 77 Install a 60 bar (or 1000 psi) pressure gauge in the charge pressure gauge port in order to monitor the charge pres- sure during start-up. Updated 2-16-00 2-60 – JLG Lift – 3120869...

  • Page 78: Semi-Track

    It is normal for the bushing to wear down to the bolt and put the loose hardware in the end of the track. for the link hole to wear oblong till it is ready to break out the end. Updated 2-16-00 3120869 – JLG Lift – 2-61...
  • Page 79 7.31 in 8.12 in 8.93 in 9.75 in (20.5 mm) (41 mm) (62 mm) (82.5 mm) (103 mm) (124 mm) (144 mm) (165 mm) (186 mm) (206 mm) (227 mm) (248 mm) Updated 2-16-00 2-62 – JLG Lift – 3120869...

  • Page 80: Preventive Maintenance And Inspection Schedule

    This machine requires periodic safety and maintenance * To be performed quarterly. inspections by a JLG Dealer. A decal located on the turn- ** Inspection and Maintenance Code 10, 12, 16 to per- table affords a place to record (stamp) inspection dates.
  • Page 81 Footswitch Controllers 1,11 Switches 1,11 Lift Up/Platform Down Disable 1,7,9 Switch* Placards and Decals Control Tags 1,11 Valves Carrier (Hoses and Cables) Lockout Cylinders (If equipped) Pins Bushings Wear Pads 1,5,6,13 Cylinders Drift Test* 2-64 – JLG Lift – 3120869...
  • Page 82 Hydraulic Hoses Hydraulic Oil Tank** 6,14 Breather Hydraulic Tank Fuel Tank 1,5,6,13 Cylinders Hood Doors Turntable Locking Pin Horizontal Limit Switch Oil Coupling Placards and Decals Swing Bearing 9, 12 Swing Brake 1,5,6 Swing Hub 3120869 – JLG Lift – 2-65...
  • Page 83 Wheel and Tire Assembly 1,5,6 Drive Motors 1,5,6 Drive Torque Hubs** Drive Brakes 1,5,6 Steer Cylinders 1,5,6,13 Steer Components Lockout Cylinders (if 5,13 equipped)* Hydraulic Hoses Placards and Decals Wheel Bearings Swing Bearing/Worm Gear 9,12 2-66 – JLG Lift – 3120869...
  • Page 84 We sell worldwide for the brands: Genie, Terex, JLG, MultiQuip, Mikasa, Essick, Whiteman, Mayco, Toro Stone, Diamond Products, Generac Magnum, Airman, Haulotte, Barreto,...
  • Page 85 For aid in troubleshooting, refer to arising in the machine will be centered in the hydraulic the Illustrated Parts Manual for hydraulic diagrams of the and electrical systems. For this reason, every effort has various circuits 3120869 – JLG Lift –...
  • Page 86 Repair or replace pump. Restricted or broken hydraulic line or fitting. Clean, repair, or replace line or fitting. Slave cylinder not functioning properly. Repair or replace cylinder. Electrical failure. See proper wiring diagram. Orifice plugged. Clean orifice. – JLG Lift – 3120869...
  • Page 87 Determine cause and repair or replace valve. Electrical malfunction. See wiring diagram. Hydraulic system oil low. Replenish oil as necessary. Restricted or broken supply line on valve bank or Clean or replace line. hydraulic pump. 3120869 – JLG Lift –...
  • Page 88 Control valve not functioning properly. Repair or replace valve. Worn seals in lift cylinder. Replace seals. Cylinder not functioning properly. Repair or replace cylinder. Boom drifts down. Worn seals in lift cylinder. Replace seals. – JLG Lift – 3120869...
  • Page 89 Repair or replace control valve. Restricted or broken hydraulic line or fitting. Clean, repair, or replace line or fitting. Pressure setting incorrect. Check pressure/re-adjust as necessary. Telescope cylinder not functioning properly. Repair or replace cylinder. 3120869 – JLG Lift –...
  • Page 90 Repair or replace valve. Foreign object(s) wedged between swing motor Remove object(s), check for damage and repair pinion and swing gear. or replace component(s) as required. Swing control switch not functioning properly. Repair or replace swing control switch. – JLG Lift – 3120869...
  • Page 91 Swing motor not functioning properly. Repair or replace swing control switch. Worn or broken teeth on swing gear or swing Replace gear(s) as required. motor pinion. Restrictor valves(s) plugged. Clean or replace restrictor valve. 3120869 – JLG Lift –...
  • Page 92 Valve spool scored. Repair or replace valve. Excessive back pressure caused by restricted Remove line and clear obstruction or replace line return line to reservoir. as necessary. Damaged valve seals. Repair or replace valve as necessary. – JLG Lift – 3120869...
  • Page 93 Damaged wiring on speed control switch or high Repair or replace wiring. engine solenoid. Drive controller not functioning properly. Replace controller. Actuator not functioning properly. Repair or replace solenoid. Excessive load on engine. Reduce load. 3120869 – JLG Lift –...
  • Page 94 Machine being moved up too steep a grade. Remove machine from grade and check that drive system operates correctly. Grade too steep. See WARNING Placard on platform for specified grades and sideslopes. Towing valve not closed. Close towing valve. 3-10 – JLG Lift – 3120869...
  • Page 95 Repair or replace motor(s). Circuit breaker open. Determine and correct cause; reset circuit breaker. Counterbalance valve sticking on return side. Adjust return counterbalance out 3 turns - cycle drive - return to original position. 3120869 – JLG Lift – 3-11...
  • Page 96 Damaged wiring on control switch or solenoid See proper wiring diagram. valve. Control switch not functioning properly. Replace switch. Restricted or broken hydraulic line on valve Clean, repair or replace line. bank, hydraulic pump or rotary coupling. (If equipped.) 3-12 – JLG Lift – 3120869...
  • Page 97 Take pressure reading at steer valve and adjust as necessary. Bent cylinder rod. Repair or replace cylinder. Damaged tie rod. Replace tie rod. Crossover relief valve sticking. Repair crossover relief valve. Cylinder packing defective. Repair or replace cylinder. 3120869 – JLG Lift – 3-13...
  • Page 98 Crossover relief valve set too low or not function- Reset, repair or replace valve as required. ing properly. Steer linkages loose. Tighten linkage. Steer wheel toe-in not set properly. Adjust toe-in for 1/4 inch overall. Spindle bushings badly worn. Replace bushings. 3-14 – JLG Lift – 3120869...
  • Page 99 Main relief valve set too low. Reset valve as required. Hydraulic system oil low. Replenish oil as necessary. Port relief set too high. Reset valve as required. Restricted or blocked return line. Repair or replace line. 3120869 – JLG Lift – 3-15...
  • Page 100 Determine and correct cause; reset circuit breaker. Engine is running. Shut down engine. Check valve in system leaking. Repair or replace check valve. Battery requires charging or will not hold a Charge or replace battery as required. charge. 3-16 – JLG Lift – 3120869...
  • Page 101 Control switch not functioning properly. Replace switch. Restricted or broken hydraulic line or fitting. Clean, repair or replace line or fitting. Pump motor solenoid not functioning properly. Replace solenoid. Pump motor not functioning properly. Repair or replace motor. 3120869 – JLG Lift – 3-17...
  • Page 102 Faulty ignition and/or starter circuit wiring. Check wiring continuity. See proper wiring dia- gram. Malfunctioning starter solenoid or motor. Replace solenoid or motor in accordance with applicable manufacturer’s manual. Faulty start switch. Replace switch. 3-18 – JLG Lift – 3120869...
  • Page 103 Function speed control will not function. Boom above horizontal. Lower boom. Horizontal limit switch malfunctioning. Repair or replace limit switch. Defective pump section. Repair or replace pump section. Electrical malfunction. See correct wiring diagram. 3120869 – JLG Lift – 3-19...
  • Page 104 SECTION 3 - TROUBLESHOOTING Figure 3-1. Electrical Components Installation - Sheet 1 3-20 – JLG Lift – 3120869...
  • Page 105 SECTION 3 - TROUBLESHOOTING Figure 3-2. Electrical Components Installation - Sheet 2 3120869 – JLG Lift – 3-21...
  • Page 106 SECTION 3 - TROUBLESHOOTING Figure 3-3. Electrical Schematic - Boom, Turntable, Chassis - Deutz - Sheet 1 3-22 – JLG Lift – 3120869...
  • Page 107 SECTION 3 - TROUBLESHOOTING 1870085C Figure 3-4. Electrical Schematic - Boom, Turntable, Chassis - Deutz - Sheet 2 3120869 – JLG Lift – 3-23...
  • Page 108 SECTION 3 - TROUBLESHOOTING Figure 3-5. Electrical Schematic - Platform -Deutz - Sheet 1 3-24 – JLG Lift – 3120869...
  • Page 109 SECTION 3 - TROUBLESHOOTING 1870085C Figure 3-6. Electrical Schematic - Platform -Deutz - Sheet 2 3120869 – JLG Lift – 3-25...
  • Page 110 SECTION 3 - TROUBLESHOOTING Figure 3-7. Hydraulic Schematic - Proportional Controls (Sheet 1 of 6) 3-26 – JLG Lift – 3120869...
  • Page 111 SECTION 3 - TROUBLESHOOTING 2792372D Figure 3-14. Hydraulic Shematic - Proportional Controls (Sheet 2 of 6) 3120869 – JLG Lift – 3-27...
  • Page 112 SECTION 3 - TROUBLESHOOTING Figure 3-14. Hydraulic Shematic - Proportional Controls (Sheet 3 of 6) 3-28 – JLG Lift – 3120869...
  • Page 113 SECTION 3 - TROUBLESHOOTING 2792372D Figure 3-14. Hydraulic Shematic - Proportional Controls (Sheet 4 of 6) 3120869 – JLG Lift – 3-29...
  • Page 114 SECTION 3 - TROUBLESHOOTING Figure 3-14. Hydraulic Shematic - Proportional Controls (Sheet 5 of 6) 3-30 – JLG Lift – 3120869...
  • Page 115 SECTION 3 - TROUBLESHOOTING 2792372D Figure 3-14. Hydraulic Shematic - Proportional Controls (Sheet 6 of 6) 3120869 – JLG Lift – 3-31...
  • Page 116 SECTION 3 - TROUBLESHOOTING This page left blank intentionally. 3-32 – JLG Lift – 3120869...

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450aj

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