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Oshkosh Corporation JLG 150HAX Service And Maintenance Manual

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Service and Maintenance Manual
Model
150HAX
P/N - 3120679
February 15, 2012
Courtesy of Crane.Market

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  • Page 1 Service and Maintenance Manual Model 150HAX P/N - 3120679 February 15, 2012 Courtesy of Crane.Market...
  • Page 2 Courtesy of Crane.Market...

  • Page 3: Bhydraulic System Safety

    INTRODUCTION SECTION A. INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS GENERAL MAINTENANCE This section contains the general safety precautions which must be observed during maintenance of the aerial FAILURE TO COMPLY WITH SAFETY PRECAUTIONS LISTED IN platform. It is of utmost importance that maintenance per- THIS SECTION COULD RESULT IN MACHINE DAMAGE, PERSON- sonnel pay strict attention to these warnings and precau- NEL INJURY OR DEATH AND IS A SAFETY VIOLATION.
  • Page 4 INTRODUCTION REVISON LOG Original Issue - May 15, 1992 Revised - January 2, 2001 Revised - February 4, 2010 Revised - February 15, 2012 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 5: Table Of Contents

    TABLE OF CONTENTS TABLE OF CONTENTS SUBJECT - SECTION, PARAGRAPH PAGE NO. SECTION A - INTRODUCTION - MAINTENANCE SAFETY PRECAUTIONS General ..............A-1 Hydraulic System Safety .
  • Page 6 TABLE OF CONTENTS (Continued) Cylinder Drift Test ............. .2-4 Platform Drift .
  • Page 7 TABLE OF CONTENTS 3.10 Swing Brake - Machines Built 1992 To Present ........3-33 Disassembly.
  • Page 8 TABLE OF CONTENTS (Continued) Cylinder Checking Procedures ........... .5-2 Cylinders w/o Counterbalance Valves - Front and Rear Steer Cylinders, Front and Rear Frame Lift Cylinders, Upper Master Cylinder, Lower Master Cylinder, Front and Rear Axle Extension Cylinders .
  • Page 9 LIST OF FIGURES LIST OF FIGURES FIGURE NO. TITLE PAGE NO. 1-1. Operator Maintenance & Lubrication Diagram ........1-5 1-2.
  • Page 10 LIST OF TABLES LIST OF TABLES TABLE NO. TITLE PAGE NO. Capacities ..............1-1 Engine Datas .

  • Page 11: Section 1 - Specifications

    SECTION 1 - SPECIFICATIONS SECTION 1. SPECIFICATIONS CAPACITIES PERFORMANCE DATA Table 1-1. Capacities Table 1-4. Performance Data Fuel Tank 68 gallons (257 liters) Maximum Drive Speed 2.7 mph (4.3 kph) @ Max RPM Hydraulic Oil Tank Approx. 124 gallons (469 liters) Maximum Travel Grade (Grade- ability) Hydraulic System...
  • Page 12 SECTION 1 - SPECIFICATIONS LUBRICATION Table 1-8. Mobil EAL 224 H Specs Table 1-6.Hydraulic Oil Type Biodegradable Vegetable Oil Hydraulic System Operating SAE Viscosity ISO Viscosity Grade 32/46 Temperature Range Grade Specific Gravity .922 0° to +23° F(-18° to -5° C) -25°F (-32°C) Pour Point, Max 0°...
  • Page 13 SECTION 1 - SPECIFICATIONS TORQUE REQUIREMENTS PRESSURE SETTINGS - PSI (BAR) Table 1-11. Torque Requirements Table 1-12. Pressure Settings - 5 Spool Proportional Valve Torque Value Interval Description (Dry) Hours Bearing To Chassis 545 ft. lbs. 50/600* 5 Spool Proportional Valve (740 Nm) Main Relief 3800...
  • Page 14 SECTION 1 - SPECIFICATIONS MAJOR COMPONENT WEIGHTS 1.10 CRITICAL STABILITY WEIGHTS Table 1-13. Major Component Weights Table 1-14. Critical Stability Weights 36 x 96 Platform Counterweight 3285 1490 Platform Level Cylinder Tire & Wheel Assembly 1020 Main Boom 6350 2880 Engine Main Lift Cylinder 8 ft.

  • Page 15: Operator Maintenance

    SECTION 1 - SPECIFICATIONS Figure 1-1. Operator Maintenance & Lubrication Diagram 1.12 OPERATOR MAINTENANCE Table 1-15. Lubrication Specifications NOTE: The following numbers correspond to those in Fig- SPECIFICATIONS ure 1-1., Operator Maintenance & Lubrication Dia- Multipurpose Grease having a minimum dripping point of 350° gram.
  • Page 16 SECTION 1 - SPECIFICATIONS 1. Torque Hubs 3. Tie Rod Center Pivot Links Lube Point(s) - 1 Fill Plug per hub Lube Point(s) - 2 Grease Fittings Capacity - Capacity - A/R Lube - EPGL Lube - MPG Interval - Check oil level at side plug on hub weekly. Interval - Every 3 months or 150 hrs of operation Change after first 3 months or 150 hours then 4.
  • Page 17 SECTION 1 - SPECIFICATIONS 6. Extending Axles Interval - Every 3 months or 150 hrs of operation Comments - Remote Fitting on Left Rear of Turnta- 9. Tower Boom Lift Cylinder Barrel End Lube Point(s) - N/A Capacity - A/R Lube - MPG Interval - Every 3 months or 150 hrs of operation Lube Point(s) - 1 Grease Fitting...
  • Page 18 SECTION 1 - SPECIFICATIONS 12. Platform Hinges 15. Platform Level Links Lube Point(s) - 3 Grease Fittings Capacity - A/R Lube - MPG Interval - Every 3 months or 150 hrs of operation 16. Level Cylinder Rod End Lube Point(s) - 2 Grease Fittings Capacity - A/R Lube - MPG Interval - Every 3 months or 150 hrs of operation...
  • Page 19 SECTION 1 - SPECIFICATIONS 19. Engine Oil Filter 24. Main Boom Pivot Pin Lube Point(s) - N/A Lube Point(s) - 1 Grease Fitting Lube - EO Capacity - A/R Comments - Refer to Engine Manual for Change Lube - MPG interval.
  • Page 20 SECTION 1 - SPECIFICATIONS 27. Upper Master Cylinder Rod End 31. Hydraulic Filter Interval - Replace filter after first 50 hours of opera- tion, then every 6 months or 300 hours thereaf- ter. 32. Air Filter Lube Point(s) - 1 Grease Fitting Capacity - A/R Lube - MPG Interval - Every 3 months or 150 hrs of operation...
  • Page 21 SECTION 1 - SPECIFICATIONS Values for Zinc Yellow Chromate Fasteners (Ref 4150707) SAE GRADE 5 BOLTS & GRADE 2 NUTS Torque Torque Torque Torque (Loctite® 242 or 271 Tensile (Loctite® 262 or Vibra- Size Bolt Dia Clamp Load Stress Area (Dry) Lubricated OR Vibra-TITE...
  • Page 22 SECTION 1 - SPECIFICATIONS SAE GRADE 8 (HEX HD) BOLTS & GRADE 8 NUTS* Torque Torque Torque (Loctite® 242 or 271 (Loctite® 262 or Vibra- Tensile Size Bolt Dia Clamp Load (Dry or Loctite® 263) Stress Area OR Vibra-TITE 111 or TITE 131) K= 0.20...
  • Page 23 SECTION 1 - SPECIFICATIONS SOCKET HEAD CAP SCREWS Magni Coating (Ref 4150701)* Torque Torque (Loctite® 242 or 271 (Loctite® 262 Tensile Clamp Load Torque Size Bolt Dia OR Vibra-TITE 111 or (Dry) K = .17 or Vibra-TITE 131) Stress Area See Note 4 140 OR Precoat 85®...
  • Page 24 SECTION 1 - SPECIFICATIONS SOCKET HEAD CAP SCREWS Zinc Yellow Chromate Fasteners (Ref 4150707)* Torque Torque Torque (Loctite® 242 or 271 (Loctite® 262 Tensile Clamp Load Size Bolt Dia (Dry) OR Vibra-TITE 111 or or Vibra-TITE 131) Stress Area See Note 4 K = .20 140 OR Precoat 85®...
  • Page 25 SECTION 1 - SPECIFICATIONS CLASS 8.8 METRIC BOLTS CLASS 8 METRIC NUTS Torque Torque (Loctite® Torque Tensile Clamp Torque (Loctite® 262 or 271 (Dry or Loctite® Size PITCH Stress Load (Lub) OR Vibra- OR Vibra- Area TITE 131) TITE 111 or 140) Sq mm [N.m]...
  • Page 26 SECTION 1 - SPECIFICATIONS CLASS 10.9 METRIC BOLTS CLASS 10 METRIC NUTS CLASS 12.9 SOCKET HEAD CAP SCREWS M3 - M5* Torque (Lub OR Loctite® Torque Torque Tensile (Dry or Loctite® Clamp or 271 (Loctite® 262 Size PITCH Stress Load Vibra-TITE 111 or Vibra-TITE...
  • Page 27 SECTION 1 - SPECIFICATIONS Magni Coating (Ref 4150701)* CLASS 12.9 SOCKET HEAD CAP SCREWS M6 AND ABOVE* Torque Torque (Lub OR Loctite® Torque Tensile (Loctite® 262 (Dry or Loctite® Clamp Load or 271 Size PITCH Stress OR Vibra-TITE See Note 4 OR Vibra-TITE Area 131)
  • Page 28 SECTION 1 - SPECIFICATIONS NOTES: 1-18 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 29: Section 2. General

    SECTION 2 - GENERAL SECTION 2. GENERAL 2.1 MACHINE PREPARATION, INSPECTION, Reference the JLG Pre-Delivery and Frequent Inspection Form and the Inspection and Preventative Maintenance AND MAINTENANCE Schedule for items requiring inspection during the perfor- mance of these inspections. Reference the appropriate General areas of this manual for servicing and maintenance proce- dures.

  • Page 30: Service And Guidelines

    SECTION 2 - GENERAL Table 2-1. Inspection and Maintenance Primary Service Type Frequency Reference Responsibility Qualification Pre-Start Inspection Prior to use each day; or User or Operator User or Operator Operator and Safety Manual At each Operator change. Pre-Delivery Prior to each sale, lease, or Owner, Dealer, or User Qualified JLG Service and Maintenance...

  • Page 31: Component Disassembly And Reassembly

    SECTION 2 - GENERAL Component Disassembly and Reassembly Hydraulic Lines and Electrical Wiring When disassembling or reassembling a component, com- Clearly mark or tag hydraulic lines and electrical wiring, as plete the procedural steps in sequence. Do not partially well as their receptacles, when disconnecting or removing disassemble or assemble one part, then start on another.

  • Page 32: Hydraulic Oil

    SECTION 2 - GENERAL Changing Hydraulic Oil fied intervals required in the Lubrication Chart in Section 1. Always examine filters for evidence of metal particles. 1. Filter elements must be changed after the first 50 hours of operation and every 300 hours (unless 3.

  • Page 33: Cylinder Drift

    SECTION 2 - GENERAL Cylinder Drift b. Flaking, pealing, scoring, or scratches on the pin surface. Table 2-2. Cylinder Drift c. Rusting of the pin in the bearing area. 4. Re-assembly of pinned joints using filament wound Max. Acceptable Drift Cylinder Bore Diameter bearings.
  • Page 34 SECTION 2 - GENERAL Table 2-3. Inspection and Preventive Maintenance Schedule INTERVAL Weekly Monthly Pre-Delivery Annual AREA Every 2 Pre-Start Preventive Preventive (Yearly) or Frequent Years Inspection Maintenance Maintenance Inspection Inspection Boom Assembly Boom Weldments 1,2,4 1,2,4 Hose/Cable Carrier Installations 1,2,9,12 1,2,9,12 Pivot Pins and Pin Retainers...
  • Page 35 SECTION 2 - GENERAL Table 2-3. Inspection and Preventive Maintenance Schedule INTERVAL Weekly Monthly Pre-Delivery Annual AREA Every 2 Pre-Start Preventive Preventive (Yearly) or Frequent Years Inspection Maintenance Maintenance Inspection Inspection Ground Controls Function Control Locks, Guards, or Detents Footswitch Emergency Stop Switches (Ground &...
  • Page 36 SECTION 2 - GENERAL Table 2-3. Inspection and Preventive Maintenance Schedule INTERVAL Weekly Monthly Pre-Delivery Annual AREA Every 2 Pre-Start Preventive Preventive (Yearly) or Frequent Years Inspection Maintenance Maintenance Inspection Inspection Walk-Around Inspection Performed Annual Machine Inspection Due No Unauthorized Modifications or Additions All Relevant Safety Publications Incorporated General Structural Condition and Welds All Fasteners, Pins, Shields, and Covers...
  • Page 37 SECTION 2 - GENERAL AMBIENT AIR TEMPERATURE 120° F(49° C) NO OPERATION ABOVE THIS AMBIENT TEMPERATURE 110° F(43° C) 100° F(38° C) 90° F(32° C) 80° F(27° C) SUMMER GRADE 70° F(21° C) FUEL ENGINE 60° F(16° C) SPECIFICATIONS 50° F(10° C) 40°...
  • Page 38 SECTION 2 - GENERAL NOTES: 2-10 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 39: Section 3 - Chassis & Turntable

    SECTION 3 - CHASSIS & TURNTABLE SECTION 3. CHASSIS & TURNTABLE 3.1 TIRES & WHEELS ment tire, ensure that all tires are inflated to the pressure recommended by JLG. Due to size variations between tire brands, both tires on the same axle should be the same. Tire Inflation The air pressure for pneumatic tires must be equal to the Wheel Replacement...

  • Page 40: Drive Torque Hub

    SECTION 3 - CHASSIS & TURNTABLE 3. The tightening of the nuts should be done in stages. b. Remove spacer (26) from planet shaft, then, Following the recommended sequence, tighten nuts using a suitable drift, drive planet shaft from car- per wheel torque chart.
  • Page 41 SECTION 3 - CHASSIS & TURNTABLE Bolt Bolt Lockwasher Cover Pipe Plug Pipe Plug Cover Cap O-ring Disconnect Rod 10. O-ring 11. Disconnect Cap 12. Bolt 13. Ring Gear 14. O-ring 15. Thrustwasher 16. Thrust Bearing 17. Input Gear 18. Thrust Spacer 19.

  • Page 42: Cleaning And Inspection

    SECTION 3 - CHASSIS & TURNTABLE Cleaning and Inspection b. Turn hub over, small diameter up. Install two pipe plugs (37) into hub. 1. Thoroughly clean all parts in an approved cleaning c. Press bearing cup (33) into small diameter end solvent.
  • Page 43 SECTION 3 - CHASSIS & TURNTABLE f. Lower hub onto spindle (30) with large open end i. Secure retaining ring (35) completely into spin- dle groove and against bearing shim. Ensure retaining ring is entirely in groove. g. Place bearing cone (32) over end of spindle and into bearing cup.
  • Page 44 SECTION 3 - CHASSIS & TURNTABLE l. Place spring (43) into spindle counterbore. 2. Position hub/spindle assembly (36 and 30) with large open end up. m. Set second spacer washer (42) on top of spring. 3. Lower internal gear (21) onto spindle. 4.
  • Page 45 SECTION 3 - CHASSIS & TURNTABLE 5. Install retaining ring (19) in groove of input shaft 8. Place o-ring (14) into counterbore of hub/spindle (20). assembly. Use grease or petroleum jelly to hold o- ring in place. 6. Place input shaft into spindle counterbore of hub/ spindle assembly.
  • Page 46 SECTION 3 - CHASSIS & TURNTABLE c. Place cluster gear over planet shaft and onto f. Bearings in cluster gear must be seated by bearing cone, with large gear on top. applying 25-50 lbs. (11-23 kg) against them and rotating cluster gear at the same time. This can be done by sliding a second spacer (26) over planet shaft and pushing downward while rotat- ing the gear.
  • Page 47 SECTION 3 - CHASSIS & TURNTABLE i. Place bearing cones (29) into cluster gear. l. While holding planet shaft in position, slide cor- rect spacer onto planet shaft. j. Place cluster gear into carrier with large gear up. EYE PROTECTION SHOULD BE WORN DURING RETAINING RING INSTALLATION.
  • Page 48 SECTION 3 - CHASSIS & TURNTABLE o. Repeat steps (a) through (n) for remaining two 12. While holding ring gear in mesh with carrier assem- cluster gears. bly, lower into internal gear (21). Small diameter cluster gear will mesh with internal gear. Slight rota- 10.
  • Page 49 SECTION 3 - CHASSIS & TURNTABLE 15. Place one thrust bearing (16) between two thrust c. Install o-ring (10) into bore of cover cap 7. Dis- washers (15) and place into carrier counterbore. connect rod (9) may be used to push o-ring down to groove in cover cap bore.
  • Page 50 SECTION 3 - CHASSIS & TURNTABLE f. Install disconnect cap (11) to cover cap with two 18. Secure cover assembly and ring gear to hub with remaining bolts (12) torqued to 70 to 80 in.lbs. four shoulder bolts (2) and lockwashers 3. Shoulder (81-92 kgcm).
  • Page 51 SECTION 3 - CHASSIS & TURNTABLE Figure 3-2. Torque Hub Carrier Timing 3120679 – JLG Lift – 3-13 Courtesy of Crane.Market...

  • Page 52: Drive Brake - Mico - Machines Built March 1992 To S/N 33476

    SECTION 3 - CHASSIS & TURNTABLE 3.3 DRIVE BRAKE - MICO - MACHINES Cleaning and Inspection BUILT MARCH 1992 TO S/N 33476 1. Clean all parts thoroughly. 2. Closely inspect all parts for excessive wear, cracks, Disassembly and chips. Replace parts as necessary. 1.
  • Page 53 SECTION 3 - CHASSIS & TURNTABLE Figure 3-3. Drive Brake - Mico (March 1992 to S/N 33746) 3120679 – JLG Lift – 3-15 Courtesy of Crane.Market...

  • Page 54: Drive Brake - Mico - Machines Built S/N 33476 To Present

    SECTION 3 - CHASSIS & TURNTABLE 3.4 DRIVE BRAKE - MICO - MACHINES 6. Position new large diameter return plate (14) in housing with tabs guided by dowel pins (20) until BUILT S/N 33476 TO PRESENT disc rests on springs (15 & 16). Disassembly DISCS (11, 14) AND FRICTION DISCS (12) SHOULD REMAIN DRY 1.

  • Page 55: Inspection

    SECTION 3 - CHASSIS & TURNTABLE Assembly 5. Remove separators (10) from housing (7). 6. Remove stack assembly, consisting of discs (23), NOTE: Lubricate all seals and o-rings with clean hydraulic return plate (8) and friction discs (22) from housing oil prior to assembly.
  • Page 56 SECTION 3 - CHASSIS & TURNTABLE Capscrew 10. Shaft 19. Bearing End Cover 11. Disc 20. Dowel Pin Bleeder Screw 12. Friction Disc 21. Housing Case Seal 13. Separators 22. Retaining Ring O-ring 14. Return Plate 23. Rotary Oil Seal Back-Up Ring 15.

  • Page 57: Free Wheeling Option

    SECTION 3 - CHASSIS & TURNTABLE 3.5 FREE WHEELING OPTION 3.6 SWING BEARING To Disengage Drive Motors and Brakes Turntable Bearing Mounting Bolt Condition (Free Wheel) for Towing, etc. Check 1. Chock wheels securely if not on a flat level surface. NOTE: This check is designed to replace the existing bear- ing bolt torque checks on JLG Lifts in service.
  • Page 58 SECTION 3 - CHASSIS & TURNTABLE Figure 3-19. Swing Bearing Tolerance Boom Placement 3-20 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 59: Wear Tolerance

    SECTION 3 - CHASSIS & TURNTABLE Check the turntable to bearing attach bolts as follows: c. Noise. d. Rough rotation. 1. Elevate the fully retracted boom to 70 degrees (full elevation). 5. If bearing inspection shows no defects, reassemble bearing and return to service. 2.
  • Page 60 SECTION 3 - CHASSIS & TURNTABLE 9. Using a suitable tool, scribe a line on outer race of underside of bearing mounting area of turntable swing bearing and frame. This line will aid in aligning base plate. bearing upon installation. Remove bolts and wash- b.
  • Page 61 SECTION 3 - CHASSIS & TURNTABLE k. Use suitable lifting equipment to carefully posi- 410 ft. lb. (555 Nm). Then, following the same tion turntable assembly above machine frame. sequence, tighten bolts to a final torque of 545 ft. lb. (740 Nm). l.

  • Page 62: Swing Bearing Torque Values

    SECTION 3 - CHASSIS & TURNTABLE Figure 3-20. Swing Bearing Torquing Sequence Swing Bearing Torque Values 3.7 SWING TORQUE HUB 1. Outer Race - 545 ft. lb. (740 Nm) JLG Threadlocker. Disassembly 2. Inner Race - 545 ft. lb. (740 Nm) JLG Threadlocker. 1.
  • Page 63 SECTION 3 - CHASSIS & TURNTABLE 1. Output Shield 8. Bearing Nut 15. Thrust Washer 21. Ring Gear 27. Thrust Washer 2. Outer Bearing Cup 9. Housing 16. Carrier 22. Thrust Washer 28. Input Cover 3. Outer Bearing Cone 10. Lip Seal 17.

  • Page 64: Cleaning And Inspection

    SECTION 3 - CHASSIS & TURNTABLE 7. Remove o-ring (6) from counterbore around rim of e. Remove tanged washer (7) from around shaft. cover. Discard o-ring. f. Set hub on something wide enough to allow shaft to fall out of hub, and hammer or press 8.

  • Page 65: Assembly

    SECTION 3 - CHASSIS & TURNTABLE Assembly l. Using torquing tool and locknut wrench, torque locknut to 175 ft. lb. (237 Nm). One tab of lock- 1. Assemble hub/shaft assembly as follows: washer should be aligned with slot in locknut when torquing is done.
  • Page 66 SECTION 3 - CHASSIS & TURNTABLE c. Apply a light coating of petroleum or multi-pur- 6. Place carrier assembly on work surface so one pose grease to inside of small end of cluster and planet shaft hole faces you and other two planet line inside of small end of cluster gear with nine- shaft holes are opposite you.

  • Page 67: Swing Brake - Ausco - Machines Built To 1992

    SECTION 3 - CHASSIS & TURNTABLE 16. Place twenty lockwashers (24) over bolt holes in 8. Remove springs (6) and spring retainer (5) from cover. housing. 17. Place twenty bolts (31) into bolt holes in cover and 9. Remove piston (13) from power plate by introducing tighten.
  • Page 68 SECTION 3 - CHASSIS & TURNTABLE Figure 3-22. Swing Brake - Ausco - Machines Built to 1992 3-30 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 69: Swing Brake - Mico - Machines Built To 1992

    SECTION 3 - CHASSIS & TURNTABLE 5. Before installing seal (4), lubricate lip of seal with 4. Remove piston (40) from end cover by inserting two system hydraulic fluid or other suitable lubricant. 1/4-20 UNC bolts into threaded holes in piston. By Face lip of seal toward outside of brake in order to turning and pulling, piston can be removed from keep gear box oil or other external contaminants out...
  • Page 70 SECTION 3 - CHASSIS & TURNTABLE Figure 3-23. Swing Brake - Mico - Machines Built to 1992 3-32 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 71: Swing Brake - Machines Built 1992 To Present

    SECTION 3 - CHASSIS & TURNTABLE Assembly 11. Install capscrews (31) and lockwashers (32). Tighten evenly to draw end cover (34) to housing and bear- ing (37) onto shaft (45). Torque capscrews to 68 Nm. NOTE: Lubricate all seals and o-rings with clean hydraulic oil prior to assembly.
  • Page 72 SECTION 3 - CHASSIS & TURNTABLE 26 13 Capscrew 10. Shaft 19. Bearing End Cover 11. Disc 20. Dowel Pin Bleeder Screw 12. Friction Disc 21. Housing Case Seal 13. Separators 22. Retaining Ring O-ring 14. Return Plate 23. Rotary Oil Seal Back-Up Ring 15.

  • Page 73: Cleaning And Inspection

    SECTION 3 - CHASSIS & TURNTABLE 5. Remove separators (13) from housing (21). 5. Insert dowel pins (20), spring retainer (17) and springs (15 & 16) in housing (21). 6. Remove stack assembly, consisting of discs (11), return plate (14) and friction discs (12) from housing 6.

  • Page 74: Swing Motor

    SECTION 3 - CHASSIS & TURNTABLE 3.11 SWING MOTOR Assembly NOTE: Prior to motor assembly, lightly oil all seals, rollers Disassembly and threaded bolt ends. NOTE: Prior to any motor disassembly, plug open ports and 1. Install new back-up ring (2) first, pushing it sealing clean all dirt from outside of motor.
  • Page 75 SECTION 3 - CHASSIS & TURNTABLE 1. Dust Seal 8. Ring Seal 2. Backup Ring 9. Vent Plug (Includes O-ring) 3. Quad Ring Seal 10. Bolt 4. Rotary Valve 11. Spline Shaft 5. Check Valve Ball 12. Body/Bearing Assembly 6. IGR Assembly 13.

  • Page 76: Pq Controllers

    SECTION 3 - CHASSIS & TURNTABLE 3.12 PQ CONTROLLERS 14. Using all applicable safety precautions, start machine and allow hydraulic oil to reach a tempera- ture of 100 to 140 degrees (38 to 60 degrees C). TRIM Adjustment 15. Depress footswitch and operate controller until trail- 1.

  • Page 77: Pump Coupling Conversion Procedures

    SECTION 3 - CHASSIS & TURNTABLE 3.13 PUMP COUPLING CONVERSION e. Release footswitch and stop machine. f. Seal ramp pot adjustment screw with a drop of PROCEDURES enamel paint to prevent maladjustment due to vibration. The following procedures are provided to assist in the con- g.

  • Page 78: Hayes Coupling

    SECTION 3 - CHASSIS & TURNTABLE Hayes Coupling PERFORM TILT ALARM SWITCH LEVELING PROCEDURE A MINI- MUM OF EVERY SIX MONTHS TO ENSURE PROPER OPERATION AND ADJUSTMENT OF SWITCH. Manual Adjustment 1. Park the machine on a flat, level surface. Ensure machine is level.

  • Page 79: Voltmeter Adjustment

    SECTION 3 - CHASSIS & TURNTABLE Voltmeter Adjustment 1800 RPM. Shut down engine. Reattach actuator cable to throttle lever, making sure that low (mid) 8. Park machine on a flat, level surface. Ensure engine setting remains the same. If necessary, machine is level and tires are filled to rated pressure.
  • Page 80 SECTION 3 - CHASSIS & TURNTABLE Figure 3-28. Throttle Checks and Adjustments - Deutz Engine 3-42 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 81: Section 4 - Boom & Platform

    SECTION 4 - BOOM & PLATFORM SECTION 4. BOOM & PLATFORM 4.1 BOOM MAINTENANCE Main Boom Removal 1. Shut down machine systems. Boom Mounted Limit Switches and Valves NOTE: Main Boom Assembly weighs approximately 6,350 NOTE: The numbers on the following descriptions corre- lb.
  • Page 82 SECTION 4 - BOOM & PLATFORM Figure 4-1. Boom Mounted Limit Switches and Valves Installation – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 83: Tower Boom Removal

    SECTION 4 - BOOM & PLATFORM Tower Boom Removal 12. Shut down machine systems. 13. Tag and disconnect all wiring to ground control box. 1. Remove main boom as outlined in Main Boom Removal. 14. Remove the bolts and lockwashers securing the lower master cylinder rod end to the tower boom.
  • Page 84 SECTION 4 - BOOM & PLATFORM Figure 4-2. Main Boom Assembly - Sheet 1 of 2 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 85 SECTION 4 - BOOM & PLATFORM 1. Base Boom 2. Mid Boom 3. Fly Boom 4. Telescope Cylinder 5. Extend Sheave 6. Fly Extend Chain 7. Fly Retract Chain 8. Chain Adjustment Assembly 9. Chain Adjustment Assembly 10. Retract Sheave 11.
  • Page 86 SECTION 4 - BOOM & PLATFORM 6. Using a suitable brass drift, carefully drive telescope 19. Remove two bolts, washers, and lockwashers secur- cylinder pin from base section. ing each trunnion pin cover to mid section. 7. Remove three locknuts and flatwashers from studs 20.

  • Page 87: Tower Boom Disassembly

    SECTION 4 - BOOM & PLATFORM 29. Remove bolts and lockwashers which attach bottom 3. Remove bolts and lockwashers securing telescope wear pads at front of outer mid section and remove cylinder mounting plate to telescope cylinder. pads and any shims. NOTE: Note and record the number and thickness of any 30.
  • Page 88 SECTION 4 - BOOM & PLATFORM 1. Base Boom 2. Mid Boom 3. Fly Boom 4. Telescope Cylinder 5. Upper Rear Wear Pads 6. Cylinder Mounting Plate Figure 4-4. Tower Boom – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 89: Inspection

    SECTION 4 - BOOM & PLATFORM Inspection 13. Using suitable lifting equipment, carefully slide tele- scope cylinder out of fly and mid sections and lower to ground or suitably supported work area. 1. Inspect all sheaves (extend chains, retract chains and telescope cylinder) for excessive groove wear, NOTE: Note and record number and thickness of any wear burrs or other damage.

  • Page 90: Main Boom Assembly

    SECTION 4 - BOOM & PLATFORM Main Boom Assembly 12. Attach loose end of extend chain to chain clevis at lower aft end of fly section. Install chain attach pins and flatwashers and secure with cotter pins. NOTE: When installing fly section wear pads, install same number and thickness of shims as were removed 13.

  • Page 91: Tower Boom Assembly

    SECTION 4 - BOOM & PLATFORM Tower Boom Assembly 24. Install trunnion pins, tapping pins into place with a soft headed mallet if necessary. Install cover plate over trunnion pins and secure to mid section with 1. If removed, align barrel end of upper master cylinder bolts, washers, and lockwashers.

  • Page 92: Tower Boom Installation

    SECTION 4 - BOOM & PLATFORM Tower Boom Installation NOTE: When installing mid section wear pads, install same number and thickness of shims as were removed during disassembly. 1. Using suitable lifting equipment, position assembled tower boom on turntable so that boom pivot holes in 10.

  • Page 93: Main Boom Installation

    SECTION 4 - BOOM & PLATFORM Main Boom Installation 4.2 BOOM CHAINS 1. Using suitable lifting equipment, position assembled Adjusting Procedures - Main Boom main boom on tower boom so that boom pivot holes in main boom and tower boom are aligned. 2.

  • Page 94: Inspection Procedure

    SECTION 4 - BOOM & PLATFORM Inspection Procedure 3. Rust and Corrosion: Rust and corrosion will cause a major reduction in the load carrying capacity of the chain, because these are primary reasons for side plate cracking. The initial lubrication at the factory is BOOM CHAINS ARE TO BE INSPECTED AT TIME OF NEXT BOOM applied in a hot dip tank to assure full penetration OVERHAUL AND WHEN DEEMED NECESSARY BY MACHINE OWNER.
  • Page 95 SECTION 4 - BOOM & PLATFORM 5. Tight Joints: All joints in the roller chain should flex 7. Stress Corrosion Cracking: The outside link freely. On roller chain, tight joints are usually caused plates, which are heavily press-fitted to the pins, are by rust/corrosion, or the inside plates “walking”...

  • Page 96: Wear Pads

    SECTION 4 - BOOM & PLATFORM 4.3 WEAR PADS 8. Chain Anchors, Sheaves, and Pins: An inspection of the chain must include a close examination of Shim up wear pads to within 5/16 in. (0.8 mm) tolerance chain anchors and sheaves. Check chain anchors between wear pad and adjacent surface.

  • Page 97: Section 5 - Hydraulics

    SECTION 5 - HYDRAULICS SECTION 5. HYDRAULICS 5.1 VALVES - THEORY OF OPERATION Relief Valves Main relief valves are installed at various points with the Solenoid Control Valves (Bang-Bang) hydraulic system to protect associated systems and com- ponents against excessive pressure. Excessive pressure Control valves used are four-way three-position solenoid can be developed when a cylinder reaches its limit of valves of the sliding spool design.

  • Page 98: Cylinder Checking Procedures

    SECTION 5 - HYDRAULICS 5.3 CYLINDER CHECKING PROCEDURES Cylinders w/Single Counterbalance Valves - Main Lift Cylinder, Tower Telescope NOTE: Cylinder checks must be performed any time a cylin- Cylinder der component is replaced or when improper system operation is suspected. Cylinders w/o Counterbalance Valves - OPERATE ALL FUNCTIONS FROM GROUND CONTROL STATION Front and Rear Steer Cylinders, Front and...

  • Page 99: Cylinders W/Dual Counterbalance Valve - Main Telescope Cylinder, Tower Lift Cylinder, Platform Slave Level Cylinder

    SECTION 5 - HYDRAULICS Cylinders w/Dual Counterbalance Valve - 5.4 CYLINDER REMOVAL AND Main Telescope Cylinder, Tower Lift INSTALLATION Cylinder, Platform Slave Level Cylinder Tower Telescope Cylinder Removal NOTE: The tower boom can be telescoped without elevating OPERATE ALL FUNCTIONS FROM GROUND CONTROL STATION the tower by overriding the plunger valves.

  • Page 100: Tower Telescope Cylinder Installation

    SECTION 5 - HYDRAULICS Tower Lift Cylinder Removal 6. Remove two bolts and lockwashers securing each of two trunnion blocks to base end of mid boom sec- tion. Remove trunnion blocks. 1. Place machine on a flat and level surface. Start engine and raise tower boom.

  • Page 101: Main Telescope Cylinder Removal

    SECTION 5 - HYDRAULICS Main Telescope Cylinder Removal 18. Using another lifting device, support sheave wheel end of cylinder and remove cylinder from boom 1. Place machine on a flat and level surface, with main assembly. boom fully retracted and in the horizontal position. 19.

  • Page 102: Main Lift Cylinder Removal

    SECTION 5 - HYDRAULICS Main Lift Cylinder Removal Lower Master Level Cylinder Removal 1. With tower boom at horizontal, depress plunger on 1. With tower boom partly raised and properly sup- limit switch in main lift circuit, located inside turnta- ported, prepare to remove lower master level cylin- ble.

  • Page 103: Lower Master Level Cylinder Installation

    SECTION 5 - HYDRAULICS Lower Master Level Cylinder Installation 7. Remove bolt and lockwasher securing level cylinder barrel attach pin to lower boom. Using an appropri- 1. With tower boom partly raised and properly sup- ate brass drift, drive out level cylinder barrel attach ported, align level cylinder barrel end bushing with pin and remove cylinder from lower boom.

  • Page 104: Cylinder Repair

    SECTION 5 - HYDRAULICS 5.5 CYLINDER REPAIR 10. Remove the piston rings. 11. Remove and discard the piston o-rings, seal rings, NOTE: The following are general procedures that apply to and backup rings. all of the cylinders on this machine. Procedures that apply to a specific cylinder will be so noted.

  • Page 105: Assembly

    SECTION 5 - HYDRAULICS 14. Inspect travel limiting collar or spacer for burrs and 6. Using suitable protection, clamp the cylinder rod in sharp edges. If necessary, dress inside diameter a vise or similar holding fixture as close to the piston surface with Scotch Brite or equivalent.
  • Page 106 SECTION 5 - HYDRAULICS 10. Place new o-rings and seals in the applicable out- NOTE: Steps (17) through (20) apply to the telescope cylin- side diameter grooves of both the piston and the cyl- der. inder head. 17. Elevate the barrel end of the cylinder to a work 11.

  • Page 107: Pressure Setting Procedures

    SECTION 5 - HYDRAULICS 5.6 PRESSURE SETTING PROCEDURES 1. Test the hydraulic pressures: a. Start the engine and stall each function. Record Cold temperatures have a significant impact on pressure the pressures. readings. JLG Industries, Inc. recommends operating the machine until hydraulic system has warmed to normal b.

  • Page 108: Stack Directional Control Valve (External Relief Adjustment Screws)

    SECTION 5 - HYDRAULICS 5 Stack Directional Control Valve (External d. Turn off the engine and apply a vacuum to the hydraulic tank. Relief Adjustment Screws) e. Remove the main relief cap. f. Remove the springs and relief cartridge. g. Install a new relief cartridge and springs and install the main relief cap.
  • Page 109 SECTION 5 - HYDRAULICS c. Adjust pressure to 3000 psi (207 bar). d. Adjust pressure to 2600 psi (179 bar). d. Bottom out Main Lift Down function. 5. Tower Lift Relief. e. Adjust pressure to 1850 psi (128 bar). a. Bottom out Tower Lift Up function. b.
  • Page 110 SECTION 5 - HYDRAULICS Figure 5-2. Valve Locations - Turntable Mounted Valves 5-14 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 111 SECTION 5 - HYDRAULICS Figure 5-3. Valve Locations - Frame Mounted Valves 3120679 – JLG Lift – 5-15 Courtesy of Crane.Market...

  • Page 112: Two Stack Directional Control Valve

    SECTION 5 - HYDRAULICS c. Bottom out Tower Lift Down function. screw clockwise to increase pressure, counterclock- wise to decrease pressure. Tighten locknut. d. Adjust pressure to 3000 psi (207 bar). 6. Bottom out Rotate Left function. 7. Loosen locknut and turn adjusting screw on oppo- site side of valve section to 2500 psi (172 bar).

  • Page 113: Four Stack Directional Control Valve

    SECTION 5 - HYDRAULICS to increase pressure, counterclockwise to decrease to increase pressure, counterclockwise to decrease pressure. Tighten locknut. pressure. Tighten locknut. 6. Bottom out Rear Steer Right function. Four Stack Directional Control Valve 7. Loosen locknut on rear steer valve section and turn adjusting screw to adjust valve section to 2000 psi 1.
  • Page 114 SECTION 5 - HYDRAULICS to increase pressure, counterclockwise to decrease to increase pressure, counterclockwise to decrease pressure. Tighten locknut. pressure. Tighten locknut. 6. Bottom out Rear Axle Extend function. 10. The two valve sections controlling the front and rear jack cylinders are controlled by system pressure 7.

  • Page 115: Hydraulic Gear Pump

    SECTION 5 - HYDRAULICS 5.7 HYDRAULIC GEAR PUMP 3. Lift off the port end cover. If prying is necessary, be careful not to damage the machined surfaces. Dowel pins will remain in either port end cover or Disassembly gear housing. Do not remove the dowel pins. DO NOT GRIP ON OR NEAR ANY MACHINED SURFACES DURING ASSEMBLY OR DISASSEMBLY.
  • Page 116 SECTION 5 - HYDRAULICS Figure 5-4. Recommended Tool List 5-20 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 117 SECTION 5 - HYDRAULICS 1. Lip Seal 2. Mounting End 3. Not Used 4. Plug 5. Dowel Pin 6. Thrust Plate 7. Channel Seal 8. Drive Gear Set 9. Square Seal 10. Gear Housing 11. Bearing Carrier 12. Connector Shaft 13.
  • Page 118 SECTION 5 - HYDRAULICS 5. Carefully remove the drive and driven gears. Avoid 7. Carefully lift of pry off the bearing carrier to prevent tapping the gear teeth together or against other damage to contact face and edges. Dowel pins will hardened surfaces.
  • Page 119 SECTION 5 - HYDRAULICS 9. Lift or pry off the first section gear housing. Be care- 11. If the pump is equipped with an outboard bearing, ful not to damage machined surfaces. Examine and place the shaft end cover in the vise with the mount- replace if necessary.

  • Page 120: Assembly

    SECTION 5 - HYDRAULICS 13. Grip the shaft end cover in a vise with the mounting 2. If bushings have been removed, deburr the bushing face down. Remove the double lip seal by inserting bores with emery cloth. Rinse parts in solvent. Air the special seal removal tool into the notch between blast all parts and wipe with a clean lint less cloth the double lip seal and the shaft end cover.
  • Page 121 SECTION 5 - HYDRAULICS 4. New plugs should be screwed in tightly. Stake plug 6. Bushings should be pressed into the bores, one at a with a prick punch at both ends of screwdriver slot time using the special installation tool and an arbor and around edges.
  • Page 122 SECTION 5 - HYDRAULICS 8. See that dowel pins are in place in any new cast- 10. If the unit is equipped with an outboard bearing, ings. Examine all dowels. Before inserting make guide the bearing into it’s recess in the shaft end sure the hole is clean and free from burrs.
  • Page 123 SECTION 5 - HYDRAULICS 12. Grease the new gasket seals and insert them into 14. Gently slip the thrust plate through the gear housing the grooves in both sides of all gear housings. Posi- and into place on the shaft end cover. The channel tion the first gear housing over the shaft end cover seal from step 13 should face the shaft end cover.
  • Page 124 SECTION 5 - HYDRAULICS 16. Slip the thrust plate with seal over gear journals and 18. Insert the connecting shaft in the spline of the drive into the housing bore. The flat side of the seal gear. Position and place the second gear housing should face up with the relief groove facing the out- on the bearing carrier as outlined in step 12.

  • Page 125: Wear Guide For Replacement

    SECTION 5 - HYDRAULICS 20. Check the plug or plugs in the port end cover to be 22. Thread the studs, washers, and nuts into the shaft sure they are tight. Follow the procedure outlined in end cover and tighten alternately or cross-corner. step 4 for new plugs.

  • Page 126: Recommended Start-Up Procedure For New Or Rebuilt Pump

    SECTION 5 - HYDRAULICS Recommended Start-up Procedure for New DRIVE SHAFTS or Rebuilt Pump Replace if there is any wear detectable by touch in the Before installing a new or rebuilt pump, back off the main seal area or at the drive coupling. 0.002 inches (0.05 mm) relief valve until the spring tension on the adjusting screw wear is the maximum allowable.
  • Page 127 SECTION 5 - HYDRAULICS Run the pump at least two minutes at no load and moder- Many repairmen measure the output at normal operating ate speed (not over 1500 rpm). if the pump becomes speed and at zero pressure, then again at 1000 psi (or the excessively hot, shut down immediately and locate the operating pressure of the equipment) and allow a volume problem source.
  • Page 128 SECTION 5 - HYDRAULICS NOTES: 5-32 – JLG Lift – 3120679 Courtesy of Crane.Market...

  • Page 129: Section 6 - Schematics

    SECTION 6 - SCHEMATICS SECTION 6. SCHEMATICS 6.1 GENERAL It should be recognized that the majority of the problems arising in the machine will be centered in the hydraulic This section contains troubleshooting information to be and electrical systems. For this reason, every effort has used for locating and correcting most of the operating been made to ensure that all likely problems in these problems which may develop.
  • Page 130 SECTION 6 - SCHEMATICS Table 6-1.Platform Assembly - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY PLATFORM LEVELING SYSTEMS Platform will not maintain level attitude. Hydraulic system oil low. Replenish oil as necessary. Dual pilot check valves dirty/ inoperative. Clean or replace as necessary. Restricted or broken hydraulic line or fitting on Clean, repair, or replace line or fitting.
  • Page 131 SECTION 6 - SCHEMATICS Table 6-1.Platform Assembly - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY CONTROL VALVES Valve spool sticking. Dirt in oil causing excessive temperature build- Flush system and change oil using recom- mended viscosity Moisture in oil. Flush system and change oil using recom- mended viscosity Incorrect valve mounting causing warping of the Loosen valve and check mounting.
  • Page 132 SECTION 6 - SCHEMATICS Table 6-2.Boom Assembly - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY BOOM ELEVATION SYSTEM. No response to lift control switch. Lift control inoperative. Repair or replace control lever. Dump valve (bypass) not operating. Determine cause and repair or replace valve. Hydraulic system oil low.
  • Page 133 SECTION 6 - SCHEMATICS Table 6-2.Boom Assembly - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Boom raises and lowers erratically. Hydraulic system oil low. Replenish oil as required. Restricted or broken hydraulic line or fitting. Clean or replace line. Lack of lubricant on cylinder shafts and/or boom Lubricate as required.
  • Page 134 SECTION 6 - SCHEMATICS Table 6-2.Boom Assembly - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Boom will not extend. Damaged wiring on control switch, solenoid Repair or replace wiring. valve or proportional valve. Solenoid valve or proportional valve not function- Repair or replace valve. ing properly.
  • Page 135 SECTION 6 - SCHEMATICS Table 6-2.Boom Assembly - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY BOOM SWING SYSTEM No response to swing control. Hydraulic system oil low. Replenish oil as necessary. Swing control lever not functioning. Repair or replace swing lever. Restricted or broken supply line on valve bank or Clean or replace line.
  • Page 136 SECTION 6 - SCHEMATICS Table 6-3.Turntable - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY POWER PLANT Engine will not start. Station power selector switch not in required Actuate switch as required. position. Circuit breaker open. Determine and correct cause; reset circuit breaker. Defective starter motor.
  • Page 137 SECTION 6 - SCHEMATICS Table 6-3.Turntable - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY CONTROL VALVES Valve Spool Sticking. Dirt in oil causing excessive temperature build- Change oil using recommended viscosity and flush system. Incorrect valve mounting causing Loosen valve and check mounting. warping of the unit.
  • Page 138 SECTION 6 - SCHEMATICS Table 6-4.Chassis - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY FRONT AXLE AREA One or both front wheels will not steer. Steering link or tie rod broken or Replace steering link, tie rod or attaching hardware missing. hardware as necessary. One or both front wheels will not rotate or rotate erratically.
  • Page 139 SECTION 6 - SCHEMATICS Table 6-4.Chassis - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Difficulty encountered when moving machine. Load capacity exceeded. Reduce load. Apply loads only in accordance with load capacity indicator. Machine being moved up too steep a grade. Remove machine from grade and check that drive system operates correctly.
  • Page 140 SECTION 6 - SCHEMATICS Table 6-4.Chassis - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Machine will not travel in forward. Hydraulic system oil low. Replenish oil as necessary. Restricted or broken hydraulic line or Clean, repair or replace line or fitting. fitting. Control valve not functioning properly.
  • Page 141 SECTION 6 - SCHEMATICS Table 6-4.Chassis - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Poor response, function shuts off slowly when command is removed. Low spool spring preload. Check for correct spring and shims in end caps. Restricted tank return line. Check for restrictions in tank return line. Sticking spool due to contamination.
  • Page 142 SECTION 6 - SCHEMATICS Table 6-4.Chassis - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Machine hard to steer or steering is erratic. Hydraulic system oil low. Replenish oil as necessary. Restricted hydraulic line or fitting. Clean, repair or replace line or fitting. Lack of lubrication.
  • Page 143 SECTION 6 - SCHEMATICS Table 6-4.Chassis - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Machine wanders; steering not firm. 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.
  • Page 144 SECTION 6 - SCHEMATICS Table 6-5.Hydraulic System - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY HYDRAULIC SYSTEM - GENERAL Hydraulic pump noisy. Air entering system through broken line or fitting. Repair or replace line or fitting. (Suction Side.) Air bubbles in oil. (Reservoir oil too low.) Replenish oil as required.
  • Page 145 SECTION 6 - SCHEMATICS Table 6-5.Hydraulic System - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY System(s) operate erratically. Sticking or binding valve spools, pistons, rods, Clean, repair, or replace components as etc. required. AUXILIARY HYDRAULIC SYSTEM. Auxiliary hydraulic pump inoperable. Circuit breaker open. Determine and correct cause;...
  • Page 146 SECTION 6 - SCHEMATICS Table 6-6.Electrical System - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY PLATFORM CONTROLS No power to platform controls. 20 Amp self-reset circuit breaker open. Check footswitch to ensure that both switches are making contact when pedal is depressed. Repair or replace footswitch as necessary.
  • Page 147 SECTION 6 - SCHEMATICS Table 6-6.Electrical System - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Travel warning horn inoperative. Damaged wiring in horn circuit. Repair or replace wiring. Damaged horn. Replace horn. Hourmeter inoperative. Damaged wiring in hourmeter circuit. Repair or replace wiring. Defective vacuum switch.
  • Page 148 SECTION 6 - SCHEMATICS Table 6-6.Electrical System - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Function occurs very rapidly when handle is moved in one direction and very slowly when moved in the opposite direction. Improper null of the handle. Check and re-adjust null. Potentiometer off center.
  • Page 149 SECTION 6 - SCHEMATICS Table 6-6.Electrical System - Troubleshooting TROUBLE PROBABLE CAUSE REMEDY Speed not proportional. “High” and “Low” pots not adjusted properly. Adjust pots to factory specifications or refer to PQ Publication 3120304 for proper adjustment. Cylinder drifts or drive motor slowly rotates when controller is returned to neutral. (high null bias) Controller failed resulting in a command at neu- Adjust or replace microswitch.
  • Page 150 SECTION 6 - SCHEMATICS Figure 6-1. Electrical Schematic - Sheet 1 of 5 6-22 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 151 SECTION 6 - SCHEMATICS 1870233 B Figure 6-2. Electrical Schematic - Sheet 2 of 5 3120679 – JLG Lift – 6-23 Courtesy of Crane.Market...
  • Page 152 SECTION 6 - SCHEMATICS Figure 6-3. Electrical Schematic - Sheet 3 of 5 6-24 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 153 SECTION 6 - SCHEMATICS 1870233 B Figure 6-4. Electrical Schematic - Sheet 4 of 5 3120679 – JLG Lift – 6-25 Courtesy of Crane.Market...
  • Page 154 SECTION 6 - SCHEMATICS 1870233 B Figure 6-5. Electrical Schematic - Sheet 5 of 5 6-26 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 155 SECTION 6 - SCHEMATICS This page left blank intentionally. 3120679 – JLG Lift – 6-27 Courtesy of Crane.Market...
  • Page 156 SECTION 6 - SCHEMATICS Figure 6-6. Hydraulic Schematic - Sheet 1 of 2 6-28 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 157 SECTION 6 - SCHEMATICS 1001110253 B Figure 6-7. Hydraulic Schematic - Sheet 2 of 2 3120679 – JLG Lift – 6-29 Courtesy of Crane.Market...
  • Page 158 SECTION 6 - SCHEMATICS NOTES: 6-30 – JLG Lift – 3120679 Courtesy of Crane.Market...
  • Page 159 Courtesy of Crane.Market...
  • Page 160 3120679 Corporate Office JLG Industries, Inc. 1 JLG Drive McConnellsburg PA. 17233-9533 (717) 485-5161 (717) 485-6417 JLG Worldwide Locations JLG Industries (Australia) JLG Latino Americana Ltda. JLG Industries (UK) Ltd JLG France SAS P.O. Box 5119 Rua Eng. Carlos Stevenson, Bentley House Z.I.

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