M O D I F I C A T I O N O F T H E M A C H I N E W I T H O U T APPROVAL BY JLG INDUSTRIES INC., IS A SAFETY • No smoking is mandatory. never refuel during electrical VIOLATION.
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Revised - May 11, 2006 Revised - October 31, 2006 Revised - April 3, 2007 Revised - October 12, 2007 Revised - January 23, 2008 Revised - March 17, 2008 Revised - October 6, 2008 – JLG Lift – 3121133...
Foam Filled - Sand 50 psi (3.4 bar) (238 Nm) 31 x 15.50-15 170 ft lbs 60 psi (4 bar) SERIAL NUMBER Grass Master (238 Nm) PLATE SERIAL NUMBER STAMPED Figure 1-1. Serial Number Location – JLG Sizzor – 3121133...
9080 lbs (4119 kg) 3° to full height 3° to full height (CSA) Chassis with Foam Filled Tires 3394RT/4394RT 3394RT 7788 lbs (3533 kg) 5° to full height 3° to full height (CE) 4394RT 9086 lbs (4121 kg) 3121133 – JLG Sizzor –...
NOTE: Hydraulic oils must have anti-wear qualities at least to API Service Classification GL-3, and sufficient chemical stability for mobile hydraulic system ser- vice. JLG Industries recommends Mobilfluid 424 DO NOT REPLACE ITEMS CRITICAL TO STABILITY WITH ITEMS hydraulic oil, which has an SAE viscosity index of 152 .
ADD and FULL sight windows on tank. Do not • Capacity - 31.5 gal (119 l) overfill tank. Any time the pump coupling is removed, coat splines of coupling with Texaco Code 1912 grease prior to assembly. 3121133 – JLG Sizzor –...
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• Interval - Every Year or 600 hours of operation • Interval - 3 Months or 150 hours of operation • Comments - Drain oil build up. Refer to Draining Oil Build Up From The Propane Regulator 3121133 – JLG Sizzor –...
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4. Push in the Emergency Switch once the engine 9. Start the engine and verify all connections are stops. secure. 10. Dispose of any drained oil per local regulations in a safe and proper fashion. – JLG Sizzor – 3121133...
8. Remove and discard the retaining bolt seal. RESIDUAL VAPOR PRESSURE WILL BE PRESENT IN THE FUEL 9. Remove and discard mounting plate to lock off O- SYSTEM. ENSURE THE WORK AREA IS WELL VENTILATED ring seal. BEFORE DISCONNECTING ANY FUEL LINE. 3121133 – JLG Sizzor –...
Annual Machine Inspection. JLG Indus- tries, Inc. recognizes a Factory-Certified Service Techni- Preparation, Inspection, and Maintenance cian as a person who has successfully completed the JLG Service Training School for the subject JLG product It is important to establish and conform to a comprehen- model.
At each Operator change. Service and Maintenance Pre-Delivery Prior to each sale, lease, or Qualified JLG Owner, Dealer, or User Manual and applicable JLG Inspection rental delivery. Mechanic inspection form. In service for 3 months or 150 hours, whichever comes first; or...
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If a bolt is too short, there will not be enough thread area to engage and hold the part properly. When replacing bolts, use only those having the same specifications of the original, or one which is equivalent. 3121133 – JLG Lift –...
Lubrication Chart. 1. Refer to Section 1 for recommendations for viscosity ranges. 2. JLG recommends Mobilfluid 424 hydraulic oil, which has an SAE viscosity of 10W-30 and a viscosity index of 152. NOTE: Start-up of hydraulic system with oil temperatures below -15°F (-26°C) is not recommended.
Pins should be inspected to ensure it is free of burrs, nicks, and scratches which would dam- NOTE: This information is based on 6 drops per minute cyl- age the bearing during installation and opera- inder leakage. tion. 3121133 – JLG Lift –...
NOTE: This machine requires periodic safety and mainte- and the “INTERVAL” at which the inspection is to take nance inspections by a JLG Dealer. A decal located place. Under the “AREA” portion of the table, the various on the frame affords a place to record (stamp) systems along with the components that make up that inspection dates.
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ENGINE WILL START AND OPERATE AT THIS TEMPERATURE GRADE WITH THE RECOMMENDED FLUIDS, A FULLY CHARGED BATTERY FUEL -20°F (-29°C) AND THE AID OF A COMPLETE JLG SPECIFIED COLD WEATHER WITH PACKAGE (IE. ENGINE BLOCK HEATER, ETHER INJECTION OR GLOW KEROSENE -30°F (-34°C)
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ENGINE WILL START AND OPERATE ON GASOLINE AT THIS TEMPERATURE WITH THE RECOMMENDED -20°F (-29°C) FLUIDS, A FULLY CHARGED BATTERY AND THE AID OF A COMPLETE JLG SPECIFIED COLD WEATHER PACKAGE (IE. ENGINE BLOCK HEATER, BATTERY WARMER AND HYDRAULIC OIL TANK HEATER) -30°F (-34°C)
ENGINE WILL START AND OPERATE ON GASOLINE AT THIS TEMPERATURE WITH THE RECOMMENDED -20°F (-29°C) FLUIDS, A FULLY CHARGED BATTERY AND THE AID OF A COMPLETE JLG SPECIFIED COLD WEATHER PACKAGE (IE. ENGINE BLOCK HEATER, BATTERY WARMER AND HYDRAULIC OIL TANK HEATER) -30°F (-34°C)
The jacks are operational (extend or retract) if the machine is in the stowed position. The proximity sensor and rotary sensor together must sense that the machine is stowed. A failure of either sensor will prevent the jacks from being activated. 3121133 – JLG Sizzor –...
3. Make sure the deck is fully lowered. Plug in the ana- lyzer and enter the service password (33271). 4. Go to CALIBRATIONS, then SET ELEV SENSOR and hit enter then right arrow. – JLG Sizzor – 3121133...
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SECTION 3 - CHASSIS & SCISSOR ARMS 6. Press the left arrow button and then enter. 2. SET 26FT ELEV (3394RT) or SET 30FT ELEV (4394RT); NOTE: Anytime the ground control board or if the rotary sen- a. Raise platform to a height of 26 feet for the...
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(replace sensor). b. NOT LEVEL - tilt sensor has either developed an 1. Ground Control Box 2. Tilt Sensor offset or it is to unlevel as mounted on the machine. – JLG Sizzor – 3121133...
The unit has a leak if the pressure gauge reading on the air checker starts to fall once the unit has been pres- NOTE: JLG P/N’s: 2780263 (2WD), 2780262 (4WD) surized. Leaks will most likely occur at main seal or wher- ever o-rings or gaskets are located.
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Cover (28) with a torque wrench to 6.3 lb ft (8.5 Nm). The Sun Gear Shaft (25) and Input Shaft (26) are now dis- connected and the machine is ready to be towed. 3-10 – JLG Sizzor – 3121133...
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5. Remove complete 1st planet stage. 2. Remove Snap Ring (24). 6. Remove ring gear fastening Bolts (20), Ring Gear (22), and O-ring (16).. 3. Remove the assembled Cover (8) with Shift Rod (33) and O-ring (23). 3121133 – JLG Sizzor – 3-11...
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DO NOT DAMAGE THE BEARING CAGE OF THE BEARING (11). DO NOT TURN THE SHAFT NUT; POSSIBILITY OF SPINDLE THREAD DAMAGE. NOTICE DO NOT DAMAGE THE BEARING CAGE OF TAPERED ROLLER BEARING. CAREFULLY REMOVE METAL CHIPS. 3-12 – JLG Sizzor – 3121133...
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Fasten theSun Gear (3) with a new Snap Ring (14) to the Planet Carrier (7). b. Mount the Support Disks (15) and the planet gears with Bearing Assembly (2, 10) heated to approximately 189.5°F/70°C onto the planet bolts. 3121133 – JLG Sizzor – 3-13...
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NOTE: Observe correct mounting position of sealing lip prior to installing the seal ring. 4. Coat bore in Supporting Ring (6) with Loctite 573 for Radial Shaft Seal Ring (17). 7. Install preassembled supporting ring onto Spindle (34). 3-14 – JLG Sizzor – 3121133...
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10. Rotate the supporitng ring repeatedly in one direc- tion only when setting the tapered roller bearing. a. Tighten Shaft Nut (4) by using an adequate device with a tightening torque of 627 lb-ft (850 Nm). 3121133 – JLG Sizzor – 3-15...
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15. Install the ring gear hex head bolts. Tighten bolts to a. Determine clearance between contact face of proper torque of 15.5 ft-lbs (21 Nm). Sun Gear (3) and Sun Gear Shaft (25). (Recom- mended clearance 1.0 -1.5mm) 3-16 – JLG Sizzor – 3121133...
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NOTE: Prior to putting into operation fill the drive with new 20. Insert Shift Rod (33) into preassembled Cover (8). oil. 23. Install Plugs (18) with new Seal Rings (19) into Cover (8). 21. Install preassembled Cover (8) into Ring Gear (22). 3121133 – JLG Sizzor – 3-17...
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Motor Disassembly 3. Disassemble guide ring: 1. Seal Ring 1. Mark port plate to the supporting axle. 2. Pressure Springs (quantity = 26) 3. Guide Ring 2. Remove port plate. 4. Disassemble retaining ring. 3121133 – JLG Sizzor – 3-19...
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5. Disassemble bearing with synchronizing plate. 8. Disassemble lamination kit. 9. Disassemble Seeger snap ring. 6. Press off pressure ring with extractor. 7. Remove pressure ring. 10. Disassemble cradle stop with 2 screws M4 x 75mm. 3-20 – JLG Sizzor – 3121133...
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14. Disassemble shaft seal ring. 15. Insert disc. Pull off bearing ring with device. Remove disc. 12. Disassemble control piston with spring. 16. Disassemble bearing ring from port plate. 13. Pull out swivel balls. 3121133 – JLG Sizzor – 3-21...
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21. Check that cylinder track is free of scratches, there are no traces of wear and no embedded foreign par- ticles. Make sure there are no scratches on the valve plate. (Replace ONLY in sets). 3-22 – JLG Sizzor – 3121133...
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(2). 26. Press bearing ring in port plate (with tool). 24. Make sure the seat of the shaft seal in the case has no damage. 27. Press bearing ring in supporting axle (with tool). 3121133 – JLG Sizzor – 3-23...
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0.05 - 0.08) is resulting in thickness of the synchronizing disc]. Grind synchronizing disc to dimension. 29. Install shaft in supporting axle (1). Put in simulation ring (2). Mount bearing with port plate , fix with 2 screws (3) 3-24 – JLG Sizzor – 3121133...
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SECTION 3 - CHASSIS & SCISSOR ARMS Motor Assembly 1. Press in swivel balls (with tool) (1). Insert shaft seal ring (with tool) (2). Insert control piston with spring (3). 3121133 – JLG Sizzor – 3-25...
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3. Mount sleeve and pressure ring in cradle stop. Insert cradle stop. NOTE: Stick with grease. 6. Assemble piston with retaining plate. Oil piston and slipper pad. 3-26 – JLG Sizzor – 3121133...
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9. Mount support ring (1) and quad ring (2) in pressure ring. Be careful not to excessively extend the rings. 10. Grease seal rings, install in supporting axle. 8. Install laminations in correct order. 3121133 – JLG Sizzor – 3-27...
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13. Align the two holes for fixation cylinder pin - port plate (item 2). Item 2 14. Mount synchronizing disc (1) and bearing (2). 12. Mount seal rings (1). Insert and line-up guide ring. 3-28 – JLG Sizzor – 3121133...
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15. Mount bearing ring with device. Mount spool. 17. Fill case with oil. Mount fixation pin. 16. Fix control plate with grease at port plate. 18. Mount and screw port plate on supporting axle. 3121133 – JLG Sizzor – 3-29...
DO NOT USE AN LPG TANK THAT IS DAMAGED. A DAMAGED wise. TANK MUST BE REMOVED FROM SERVICE. FROST ON THE SUR- FACE OF A TANK, VALVES, OR FITTINGS INDICATES LEAKAGE. A STRONG ODOR OF LPG FUEL CAN INDICATE A LEAK. 3-30 – JLG Sizzor – 3121133...
(DTC) is set and will be displayed on the source of the problem. JLG Control System Analyzer. Refer to Section 6 - JLG Control System. If no matching symptom is available, analyze the com-...
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As long as the fault is present, the engine can be restarted. It will run in the previously established injection sequence 3-32 – JLG Sizzor – 3121133...
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Camshaft Position Sensor (CMP) Sensor Illegal Pattern Engine Control Module (ECM) Fault Illegal Operation Engine Control Module (ECM) Fault Illegal Interruption Engine Control Module (ECM) Fault COP (Computer Operating Properly) Failure System Voltage Low System Voltage High 3121133 – JLG Sizzor – 3-33...
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If the ECM is replaced, the new ECM will need to be pro- grammed. An IBM-compatible computer and software containing the correct program and calibration for the application are required to program the ECM. 3-34 – JLG Sizzor – 3121133...
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The MAP sensor is used to determine the following: injectors, electronic governor, etc., by control ling the ground or the power feed circuit through transistors or • Engine vacuum level for engine control purposes. other solid state devices. • Barometric pressure (BARO) 3-36 – JLG Sizzor – 3121133...
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• When testing for opens and shorts, do not ground or apply voltage to any of the ECM's circuits unless age measurements, use only a digital voltmeter with an instructed to do so. input impedance of at least 10 megohms. 3121133 – JLG Sizzor – 3-37...
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The fuel is injected under pressure in a conical spray pat- tern at the opening of the intake valve. Excess fuel not used by the injectors passes through the fuel pressure regulator before being returned to the fuel tank. 3-38 – JLG Sizzor – 3121133...
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14.7 parts of air to 1 part of gasoline by weight, which provides the most effi- cient combustion. Because of the constant measuring and adjusting of the air/fuel ratio, the fuel injection system is called a "closed loop" system. 3121133 – JLG Sizzor – 3-39...
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When the ECM detects a change in engine load, it can adjust idle speed by changing the PWM signal to the governor. 3-40 – JLG Sizzor – 3121133...
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The sensor initiates the reference ECM responds by reducing the "on" time of the fuel injec- pulses which the ECM uses to calculate RPM and crank- tors, thus leaning out the mixture. shaft position. 3121133 – JLG Sizzor – 3-41...
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"waste spark." The primary coils in the coil pack are triggered by the "Ignition Coil Feed #1" and "Ignition Coil Feed #2" Signals from the ECM. 3-42 – JLG Sizzor – 3121133...
The EMR2 consists of the sensors, the control unit and the In order to switch the engine off, the EMR2 is switched in a actuator. Engine-side controls as well as the JLG Control de-energized fashion over the ignition switch. A strong...
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SENSOR JLG SYSTEM HANDLES ENGINE START/ STOP; EMR2 TAKES CONTROL OF THE ENGINE AT 700RPM GLOW PLUG JLG SYSTEM USES JLG ANALYZER TO REPORT FAULTS DIAGNOSIS INTERFACE/CAN-BUS; JLG SYS- TEM USES THIS TO CONTROL THE ENGINE & OIL PRESSURE FAULT REPORTING.
When inspecting the electri- cal system use the following: • Check and clean the battery terminal connections and insure the connections are tight 3-58 – JLG Sizzor – 3121133...
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8. Start the engine and check for oil leaks. 9. Stop the engine and check the oil level to insure the oil level is at "FULL". 10. Dispose of the oil and filter in a safe manner. 3121133 – JLG Sizzor – 3-59...
Electronic Throttle Control and the ECM. The ECM contains a dual calibration; one controls the gasoline fuel system during gasoline operation and one controls the LPG fuel system during LPG operation. Figure 3-28. Electric Fuel Lock Off 3121133 – JLG Sizzor – 3-61...
As the AVV increases in the secondary chamber the secondary diaphragm is drawn further down forcing the secondary valve lever to open wider. Figure 3-32. ETC throttle control device Figure 3-31. Air Fuel Mixer 3121133 – JLG Sizzor – 3-63...
The primary components of the Gasoline Multi Point Fuel Injection (MPFI) fuel system are the fuel tank, electric fuel pump, fuel pressure and temperature sensor manifold, Figure 3-34. ECM Assembly fuel filter and fuel rail. 3-64 – JLG Sizzor – 3121133...
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Fuel that enters the bleed circuits mance and emission control. through they bypass valve in the manifold is returned to the fuel tank. Figure 3-36. Gasoline Fuel Pressure and Temperature Manifold Assembly 3121133 – JLG Sizzor – 3-65...
BE SURE TO REINSTALL THE FILTER MAGNET INTO THE HOUS- ING BEFORE INSTALLING NEW SEAL. 1. Install the mounting plate to lock off O-ring seal. 2. Install the retaining bolt seal. 3. Install the housing seal. 3-66 – JLG Sizzor – 3121133...
NOTE: Residual vapor pressure will be present in the fuel tighten into proper location, connect the electrical system. connector. 4. Disconnect the electrical connector to the Electric 7. Connect the fuel supply line and tighten until fully Lock off . seated. 3121133 – JLG Sizzor – 3-67...
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1. Install the regulator to the actuator section using the 3. Start the vehicle and check for proper operation. six (6) retaining screws and tighten 70 in lbs (8 Nm). 2. Install the EPR refer to EPR Installation. 3-68 – JLG Sizzor – 3121133...
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Notice the orientation of the air inlet and throttle body cover. NOTICE LIGHTLY LUBRICATE BOTH THROTTLE CONTROL DEVICE TO ADAPTER O-RINGS. 1. Install the O-ring on throttle body. Press it down to the bottom of the surface. 3121133 – JLG Sizzor – 3-69...
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3. Remove and discard the mixer to adapter gasket. NOTICE INSTALLATION THE VAPOR SUPPLY HOSE IS SPECIFICALLY DESIGNED, DO NOT USE HOSE MATERIAL OR LENGTH OTHER THAN JLG SPEC- IFIED PARTS. NOTICE COVER THROTTLE BODY ADAPTER OPENING TO PREVENT 1. Install hose clamps and set back on each hose.
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4. Verify engine is in closed loop and no warning lights are illuminated. 6. Check for any DTC codes and clear. 7. Verify engine is in closed loop and no warning lights are illuminated. 3121133 – JLG Sizzor – 3-71...
This vacuum signal is most commonly referred to as air valve vacuum. In the mixer, the fuel mixes with the air entering the engine. This air/ fuel mixture is then drawn into the engine for combustion. 3-72 – JLG Sizzor – 3121133...
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1- 3 PSI Go to Step 22 Go to Step 13 (LPR). 2. Crank the engine and observe the pressure reading for the LPR primary pres- sure. Is the fuel pressure ABOVE the specified value? 3121133 – JLG Sizzor – 3-73...
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Is the action complete? Replace the lock-off. Refer to Lock-off Replacement. Go to Step 26 Is the action complete? Replace the mixer assembly. Refer to Fuel Mixer Replacement. Go to Step 26 Is the action complete? 3-74 – JLG Sizzor – 3121133...
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1. Disconnect all test equipment System OK 2. Install the primary and secondary test port plugs. 3. Start the engine. 4. Using SNOOP or equivalent, leak check the test port plugs. Is the action complete? 3121133 – JLG Sizzor – 3-75...
SECTION 3 - CHASSIS & SCISSOR ARMS 3.15 JOYSTICK CONTROLLER Figure 3-43. Joystick Controller - (JLG P/N 1600308) Table 3-10. Joystick Specifications Table 3-11. Joystick Plug Loading Chart Input Voltage 4.3V (±0.1V) Terminal Color Function Centered Output Voltage 2.2V (±0.1V)
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SECTION 3 - CHASSIS & SCISSOR ARMS Figure 3-44. Joystick Controller - (JLG P/N 1600403) Table 3-12. Joystick Specifications Table 3-13. Joystick Plug Loading Chart Input Voltage Terminal Color Function Centered Output Voltage 4.25V to 2.60V Yellow Steer Right Reverse Voltage 4.60V to 4.80V...
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If a visual and physical check does not locate the cause of the problem, drive the vehicle with a scan tool. When the prob- lem occurs, an abnormal voltage or scan reading indicates the problem may be in that circuit. 3-78 – JLG Sizzor – 3121133...
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² Check for the following: - Vacuum leaks - Improper valve timing - Low compression - Bent pushrods - Worn rocker arms - Broken or weak valve springs - Worn camshaft lobes. 3121133 – JLG Sizzor – 3-79...
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- Improper valve timing - Low compression - Bent pushrods - Worn rocker arms - Broken or weak valve springs - Worn camshaft lobes. ² Check the intake and exhaust manifolds for casting flash. 3-80 – JLG Sizzor – 3121133...
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² Check the Manifold Absolute Pressure (MAP) sensor response and accuracy. ² Check LPL electrical connection ² Check the mixer air valve for sticking or binding. ² Check the mixer module assembly for proper installation and leakage. ² Check the EPR electrical connections. 3121133 – JLG Sizzor – 3-81...
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LPG to a vehicle operating on gasoline as the fuels do have different drive feel characteristics ² Remove the air filter and check for dirt or restriction. ² Check the vehicle transmission Refer to the OEM transmission diagnostics. 3-82 – JLG Sizzor – 3121133...
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² Check the spark plugs. Remove the plugs and inspect them for the following conditions: - Wet plugs - Cracks - Wear - Improper gap - Burned electrodes - Heavy deposits ² Check the ignition wires for the following items: - Cracking - Hardness - Proper connections 3121133 – JLG Sizzor – 3-83...
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DEFINITION: The engine has a power variation under a steady throttle or cruise. The vehicle feels as if it speeds up and slows down with no change in the accel- erator pedal. Preliminary Checks Refer to Important Preliminary Checks. Sensor Checks ² Check Heated Exhaust Gas Oxygen Sensor (HEGO) performance. 3-84 – JLG Sizzor – 3121133...
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Additional Check ² Check the ECM grounds for being clean, tight, and in their proper locations. ² Check the generator output voltage. ² Check the vacuum hoses for kinks or leaks. ² Check Transmission 3121133 – JLG Sizzor – 3-85...
OPERATE ALL FUNCTIONS FROM GROUND CONTROL STATION ONLY. 4. Raise machine platform approximately 9 ft (2.7 m) on the 3394RT or 10 ft (3.1 m) on the 4394RT. 1. Using all applicable safety precautions, activate hydraulic system. 5. Place DRIVE control switch to REVERSE position and carefully drive the machine off the block and 2.
11. Raise machine platform approximately 9 ft (2.7 m) on the 3394RT or 10 ft (3.1 m) on the 4394RT. 12. Place DRIVE control switch to REVERSE position and carefully drive the machine off the block and ramp.
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Progressively tighten the cap screw(s) until the bushing is loose on the piston. 7. Attach a suitable pulling device to the cylinder rod port block end or cylinder rod end, as applicable. – JLG Lift – 3121133...
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17. If applicable, inspect piston rings for cracks or other Dress threads as necessary. damage. Replace as necessary. 8. Inspect seal and o-ring grooves in piston for burrs and sharp edges. Dress applicable surfaces as nec- essary. 3121133 – JLG Lift –...
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SECTION 4 - HYDRAULICS 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.
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4. Assemble the tapered bushing loosely into the pis- ton and insert JLG capscrews (not vendor cap- Figure 4-13. Seating the Tapered Bearing 7. Retorque the capscrews evenly and progressively in rotation to the specified torque value.
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19. Position the cylinder barrel in a suitable holding fix- ture. NOTICE 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. – JLG Lift – 3121133...
The inlet line leading from the reservoir to the pump should be filled prior to start-up. Check inlet line for prop- erly tightened fittings and make sure it is free of restric- tions and air leaks. 3121133 – JLG Lift –...
When oil begins to flow, should be retightened to their specified torque. the line is full, the air has been purged, and the fitting can be retightened to its specified torque. If the tank 4-10 – JLG Lift – 3121133...
(1) by prying it out with a large screw- from the factory. If the body or rear cover is replaced dur- driver. ing overhaul, scribe a match mark on the new part in the same location as on the part it replaced. 3121133 – JLG Lift – 4-11...
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6. Inspect body for wear and scoring. If gear contact wear on low pressure side (inlet) exceeds 0.005 in. (.127mm) depth, replace body. If the body is usable, lightly wipe and remove burr’s with suitable de-burr- ing tool. 4-12 – JLG Lift – 3121133...
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6. Set the body (13) onto the front cover (5), matching the scribes marks on the body and front cover. The dowel pins (7) should go into the mating holes on the front cover (5). 7. Install drive gear (12), and driven gear (11). 3121133 – JLG Lift – 4-13...
42 - 49 7. Main Relief 25 - 30 35 - 42 8. Steer Relief 30 - 35 42 - 49 9. MG Port 10. MS Port 11. MP1 Port Figure 4-15. Main Valve Torque Values 4-14 – JLG Lift – 3121133...
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Cold temperatures have a significant impact on pressure 6. Bottom out Steer Right and Steer Left functions and readings. JLG Industries Inc. recommends operating the adjust each Steer Crossover Relief to 2800 psi (193 machine until the hydraulic system has warmed to normal bar).
Pressure Setting Procedure item Torque Cold temperatures have a significant impact on pressure readings. JLG Industries Inc. recommends operating the 40 ft-lbs machine until the hydraulic system has warmed to normal (54 Nm) operating temperatures prior to checking pressures. JLG 23 ft-lbs Industries Inc.
NOTE: Power Deck Manifold Valve is located on the under- EP, ET 24 ft-lbs (32.5 Nm) side of the platform. Dual extension decks are equipped with two Manifold Valves. Single extension EPR, EPB 32 ft-lbs (43.4 Nm) decks have only one Manifold Valve. 3121133 – JLG Lift – 4-19...
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1. Locknut 6. Spacer Tube 11. Seal 2. Piston 7. Head 12. Wiper Ring 3. Seal 8. Rod 13. Retaining Ring 4. O-Ring 9. O-Ring 5. Barrel 10. Back-up Ring Figure 4-33. Deck Extension Cylinder 3121133 – JLG Lift – 4-29...
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5. Oscillate axle fully in the opposite direction and repeat steps 3 and 4. 3. Open the bleeder valve at the top of the retracted cylinder approx. 1/2 turn and open bleeder valve at the bottom of extended cylinder approx. 1/2 turn. 4-30 – JLG Lift – 3121133...
SECTION 5 - JLG CONTROL SYSTEM SECTION 5. JLG CONTROL SYSTEM HAND HELD ANALYZER menu: Analyzer Display HELP: PRESS ENTER Enter Key Escape Key Stores and selects Top Level, Sub To return home or access Level, and item menus previous menu Left &...
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SECTION 5 - JLG CONTROL SYSTEM If you press ENTER, at the HELP:PRESS ENTER display, NOTE: The cable has a four pin connector at each end of the cable; the cable cannot be connected back- and a fault is present during power up, the analyzer dis- wards.
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SECTION 5 - JLG CONTROL SYSTEM Changing the Access Level of the Hand Held Analyzer: When the analyzer is first connected, you will be in access level 2 which enables you to only view most configuration settings which cannot be changed until you enter a pass-...
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SECTION 5 - JLG CONTROL SYSTEM Adjusting Parameters Using the Hand Held Machine Setup Analyzer When a machine digit item is selected, press the UP or DOWN arrow keys to adjust its value, for example: Once you have gained access to level 1, and a personality...
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SECTION 5 - JLG CONTROL SYSTEM NOTE: Refer to the appropriate Machine Personality Set- NOTICE tings Table, and the Machine Setup Table in the JLG IT IS A GOOD PRACTICE TO AVOID PRESSURE-WASHING ELEC- Service Manual for the default settings.
ELEVATION SENSOR DISAGREEMENT Reported when elevation prox switch is closed when the 26 ft (3394RT) or 30 ft (4394RT) voltage is reached on the elevation angle sensor. (prevents further lift up from platform controls) Flash code 2/1 indicates issues at power up.
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code Flash code 2/2 indicates difficultly with the platform controls. TRIGGER SWITCH WIRING SHORTED HIGH IN PLAT-...
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code Flash code 2/3 indicates difficultly with ground controls. FUNCTION LOCKED OUT – GROUND LIFT UP PERMA-...
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code Flash code 2/5 indicates issues that may cutout functions. ELEV ANGLE SENSOR FAULTY – NOT MOUNTED OR...
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code Flash code 2/6 indicates leveling jack or power deck issues. FRONT LEFT LEVELING JACK OPEN CIRCUIT Reported by the I/O module and during system test when the front left leveling jack is open circuit.
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code LEVELING JACK EXTEND VALVE SHORT TO GROUND Reported by the I/O module and during system test when the leveling jack extend valve is short to ground.
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code Flash code 4/3 indicates engine issues. FUEL SENSOR SHORT TO BATTERY Reported when the fuel sensor is reading a value that is much too high.
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SECTION 5 - JLG CONTROL SYSTEM Table 5-1. Fault Code Listing - Software P1.X Fault Flash Communicated (Displayed on Analyzer) Fault Description Priority Code Flash codes 8/* indicate load cells issues. LSS CELL #1 ERROR Reported when there is a problem with cell #1 on the LSS.
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SECTION 5 - JLG CONTROL SYSTEM 5-14 – JLG Lift– 3121133...
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SECTION 5 - JLG CONTROL SYSTEM 3121133 – JLG Lift – 5-15...
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SECTION 5 - JLG CONTROL SYSTEM 5-16 – JLG Lift– 3121133...
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SECTION 5 - JLG CONTROL SYSTEM Table 5-2. Machine Model Adjustment Model Default Values Adjustment Adjustment Range 3394RT 2WD 3394RT 4WD 4394RT 2WD 4394RT 4WD DRIVE Accel 0.1 - 5.0 (sec) Decel 0.1 - 3.0 (sec) Min Forward 0 - 35%...
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SECTION 5 - JLG CONTROL SYSTEM NOTE: When configuring an RT, the Machine Configuration must be completed before any Personality settings can be changed. Changing the Personality settings first and then changing the Model of the Machine Configuration will cause the Personality settings to return to default values.
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SECTION 5 - JLG CONTROL SYSTEM Table 5-3. Machine Configuration Programming Information Configuration Digit Setting Description Default Number NOT INSTALLED – Load Sensing System (LSS) is not fitted to the vehicle. CUTOUT PLT – Load Sensing System (LSS) is fitted, and Platform Controls are pre- vented in the event of an Overload.
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SECTION 5 - JLG CONTROL SYSTEM NOTE: Bold Italic Numbers indicate the default setting. Plain text indicates another available selection. Bold, Italic underlined numbers indicate the default when the option is factory installed. 3394RT 2WD ANSI USA ANSI EXPORT AUSTRALIA...
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SECTION 5 - JLG CONTROL SYSTEM NOTE: .Bold Italic Numbers indicate the default setting. Plain text indicates another available selection. Bold, Italic underlined numbers indicate the default when the option is factory installed. 3394RT 4WD ANSI USA ANSI EXPORT AUSTRALIA...
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SECTION 5 - JLG CONTROL SYSTEM NOTE: Bold Italic Numbers indicate the default setting. Plain text indicates another available selection. Bold, Italic underlined numbers indicate the default when the option is factory installed. 4394RT 2WD ANSI USA ANSI EXPORT AUSTRALIA...
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SECTION 5 - JLG CONTROL SYSTEM NOTE: Bold Italic Numbers indicate the default setting. Plain text indicates another available selection. Bold, Italic underlined numbers indicate the default when the option is factory installed. 4394RT 4WD ANSI USA ANSI EXPORT AUSTRALIA...
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SECTION 5 - JLG CONTROL SYSTEM NOTES: 5-24 – JLG Lift– 3121133...
= kilo = 1,000 * (Displayed Number) m = milli = (Displayed Number) / 1,000 µ = micro = (Displayed Number) / 1,000,000 Example: 1.2 kΩ = 1200 Ω Example: 50 mA = 0.05 A 3121133 – JLG Sizzor –...
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• Circuit power must be turned OFF before testing resistance • Disconnect component from circuit before testing • If meter is not auto ranging, set it to the correct range (See multimeter’s operation manual) • Use firm contact with meter leads – JLG Sizzor – 3121133...
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(See multi meter’s operation manual) • Use firm contact with meter leads • Use firm contact with meter leads • First test meter and leads by touching leads together. Meter should produce an audible alarm, indicating continuity 3121133 – JLG Sizzor –...
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One can find the continuity of two wires, here #1 and #2, at once by following steps 1 through 4. If there is a problem the third wire is used to troubleshoot the other wires. To find the problem, start at step 1 and use the entire procedure. – JLG Sizzor – 3121133...
2. Pierce one of the unused wire seals to allow the trapped air inside the housing to escape. 3. Install a hole plug into this and/or any unused wire seal that has silicone dielectric compound escaping from it. Figure 6-5. AMP Connector 3121133 – JLG Sizzor –...
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(See Figure 6-8. Connector Assembly (3 of 4)). 4. Slide the wedge lock into the housing until it is flush with the housing (See Figure 6-9. Connector Assembly (4 of 4)). Figure 6-7. Connector Assembly (2 of 4) – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-8. Connector Assembly (3 of 4) Figure 6-9. Connector Assembly (4 of 4) 3121133 – JLG Sizzor –...
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The wedge lock has slotted openings in the forward, or mating end. These slots accommodate circuit testing in the field, by using a flat probe such as a pocket knife. DO NOT use a sharp point such as an ice pick. – JLG Sizzor – 3121133...
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This nullifies the effectiveness of the connector seals and could result in system failure. Figure 6-11. Connector Installation 3121133 – JLG Sizzor –...
7. Hold the rear seal in place, as removing the contact may displace the seal. HD30/HDP20 Series Assembly Figure 6-14. HD/HDP Contact Installation 8. Grasp contact about 25mm behind the contact crimp barrel. 9. Hold connector with rear grommet facing you. 6-10 – JLG Sizzor – 3121133...
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12. Slide tool along into the insert cavity until it engages contact and resistance is felt. 13. Pull contact-wire assembly out of connector. Figure 6-17. HD/HDP Unlocking Contacts NOTE: Do Not twist or insert tool at an angle. 3121133 – JLG Sizzor – 6-11...
Another type of limit switch used by JLG is the inductive proximity switch, also referred to as a "prox switch". Inductive proximity switches are actuated only by ferrous metal (metal that contains Iron, such as steel) near the switch. They do not require contact, and must be energized to actuate.
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Also, the technician can mea- sure the voltage at both power terminals with respect to battery ground. The difference between those two measure- ments is the voltage applied to the load. 3121133 – JLG Sizzor – 6-13...
SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS SCHEMATICS Figure 6-18. Electrical Schematic - Dual Fuel - Sheet 1 of 3 6-14 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-19. Electrical Schematic - Dual Fuel - Sheet 2 of 3 3121133 – JLG Sizzor – 6-15...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS 1870143 H Figure 6-20. Electrical Schematic - Dual Fuel - Sheet 3 of 3 6-16 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS NOTES: 3121133 – JLG Sizzor – 6-17...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-21. Electrical Schematic Diesel (Prior to S/N 138634) - Sheet 1 of 3 6-18 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-22. Electrical Schematic Diesel (Prior to S/N 138634) - Sheet 2 of 3 3121133 – JLG Sizzor – 6-19...
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ALL TRANSDUCERS ARE WIRED USING A 3 CONDUCTOR 1870153 G SHIELDED CABLE. THE SHIELD FOR EACH CABLE SHOULD BE TERMINATED WITH THE RESPECTIVE BLACK WIRE AT J3. Figure 6-23. Electrical Schematic Diesel (Prior to S/N 138634) - Sheet 3 of 3 6-20 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS NOTES: 3121133 – JLG Sizzor – 6-21...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-24. Electrical Schematic - Dual Fuel GM - Sheet 1 of 5 6-22 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-25. Electrical Schematic - Dual Fuel GM - Sheet 2 of 5 3121133 – JLG Sizzor – 6-23...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-26. Electrical Schematic Dual Fuel - GM - Sheet 3 of 5 6-24 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS NOTES: 3121133 – JLG Sizzor – 6-25...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-27. Electrical Schematic Dual Fuel - GM - Sheet 4 of 5 6-26 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS 1870204 E Figure 6-28. Electrical Schematic Dual Fuel - GM - Sheet 5 of 5 3121133 – JLG Sizzor – 6-27...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-29. Electrical Schematic Diesel (S/N 138634 to Present) - Sheet 1 of 3 6-28 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-30. Electrical Schematic Diesel (S/N 138634 to Present) - Sheet 2 of 3 3121133 – JLG Sizzor – 6-29...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS 1870190 D Figure 6-31. Electrical Schematic Diesel (S/N 138634 to Present) - Sheet 3 of 3 6-30 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS NOTES: 3121133 – JLG Sizzor – 6-31...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-32. Hydraulic Schematic 4WD - Sheet 1 of 4 6-32 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-33. Hydraulic Schematic 4WD - Sheet 2 of 4 3121133 – JLG Sizzor – 6-33...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-34. Hydraulic Schematic 4WD - Sheet 3 of 4 6-34 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS 2792543 D Figure 6-35. Hydraulic Schematic 4WD - Sheet 4 of 4 3121133 – JLG Sizzor – 6-35...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-36. Hydraulic Schematic 2WD - Sheet 1 of 4 6-36 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-37. Hydraulic Schematic 2WD - Sheet 2 of 4 3121133 – JLG Sizzor – 6-37...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS Figure 6-38. Hydraulic Schematic 2WD - Sheet 3 of 4 6-38 – JLG Sizzor – 3121133...
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SECTION 6 - GENERAL ELECTRICAL INFORMATION & SCHEMATICS 2792544D Figure 6-39. Hydraulic Schematic 2WD - Sheet 4 of 4 3121133 – JLG Sizzor – 6-39...
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Left Note: “*” on a line indicates a Power Deck Sandwich Valve non-straight hose end Mounted on top of Main Manifold Hydraulic Oil Tank Aux. Pump Figure 6-43. Hydraulic Diagram - Deck Extension (Single) 3121133 – JLG Sizzor – 6-43...
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