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Clark GEX20 Service Manual
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Clark GEX20 Service Manual

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RATED CAPACITY : 2000~3000kg
GEX20-30
SERVICE MANUAL
Part No. 8051044
Book No. SM-765
Dec. 2006
#40-1,Ungnam-Dong,
changwon-city, Kyungnam,
Korea

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Summary of Contents for Clark GEX20

  • Page 1 GEX20-30 SERVICE MANUAL RATED CAPACITY : 2000~3000kg Part No. 8051044 Book No. SM-765 Dec. 2006 #40-1,Ungnam-Dong, changwon-city, Kyungnam, Korea...
  • Page 3 This manual consists of “base” module that pertains You may, however, purchase specific modules and to all GEX20-30 models and other modules that per- expand your manual to fully cover multiple models. tain only to specific models. Manuals shipped with...
  • Page 4 NOTE : SM765, Nov ’06...
  • Page 5 CONTENTS Contents by Group and Section (Alphabetical listing of contents appears on next page.) Contents are listed here by Group number and name followed by Section number and name: SAFE MAINTENANCE 6. Parking Brake Service 1. Safety STEERING COLUMN AND GEAR 2.
  • Page 6 CONTENTS COUNTERWEIGHT AND CHASSIS 1. Counterweight Specifications and Description 2. Counterweight Removal and Installation 3. Overhead Guard Removal and Installation 4. Floor Plate, Seat, and Seat Deck Removal and Installation SPECIFICATIONS 1. Nameplate and Decals 2. General Specifications 3. Hydraulic Fitting Tightening Procedure CONTENTS -2 SM 765, Nov '06...
  • Page 7 CONTENTS Alphabetical Listing of Topics (Contents are listed by order of Group and Section numbers on previous page.) Contents are listed here by topic followed by the Group#-Section# the topic appears in: Battery Service............12-1 Main Hydraulic System Specifications and Description ...............
  • Page 8 NOTE : SM 765, Dec '04 Alphabetical Listing of Topics...
  • Page 9 REVISION HISTORY Nov. 2006 When new or revised information is published to update this Mark Indication Action required manual the action to be taken with the pages is indicated in the table. ❍ Page to be newly added Pages not marked are not currently revised, but are ●...
  • Page 10 REVISION HISTORY Revision Revision Revision Revision Mark Page number Mark Page number Mark Page number Mark Page number 20-4-1 25-4-2 29-1-5 34-2-3 20-4-2 25-5-1 29-1-6 34-2-4 20-4-3 25-5-2 29-2-1 34-3-1 20-5-1 25-5-3 29-2-2 34-3-2 20-5-2 25-5-4 29-2-3 34-3-3 20-6-1 25-5-5 29-3-1 34-3-4 20-6-2...
  • Page 11 REVISION HISTORY Revision Revision Revision Revision Mark Page number Mark Page number Mark Page number Mark Page number 38-1-1 38-1-2 38-2-1 38-2-2 38-2-3 38-3-1 38-3-2 38-4-1 38-4-2 38-4-3 40-1-1 40-1-2 40-1-3 40-1-4 40-1-5 40-1-6 40-2-1 40-2-2 40-2-3 40-2-4 40-3-1 SM 765, Nov ’06 REVISION HISTORY - 3...
  • Page 12 NOTE : REVISION HISTORY SM 765, Nov ’06...

  • Page 13: Safe Maintenance

    GROUP SA SAFE MAINTENANCE GROUP SA SAFE MAINTENANCE Safety ..............Section 1 Lifting, Jacking, and Blocking the Truck..Section 2 Towing ............... Section 3 SM 765, Nov ’06 Group SA SAFE MAINTENANCE...
  • Page 14 NOTE : Group SA SAFE MAINTENANCE SM 765, Nov ’06...
  • Page 15 Group SA, Safe Maintenance Section 1 Safety Safety Signs and Messages ........2 Safe Maintenance Practices ........2 General Shop Precautions ........4 SM 765, Nov ’06 Safety • SA-1-1...

  • Page 16: Safety Signs And Messages

    Raise drive wheels off of floor or disconnect power source. Use blocks or other positive truck The above terms have been adopted by Clark Material positioning devices Handling Company. The same terms may be used in dif- c. Disconnect battery before working on the electri- ferent context in service literature supplied directly or cal system.
  • Page 17 Put directional control in neutral. tires, are to be installed per the manufacturer’s proce- c. Apply the parking brake. dures. Always use genuine CLARK or CLARK d. Turn key switch OFF. approved parts. e. Put blocks at the wheels if truck is on an incline.
  • Page 18 However, if a degreaser is used, we recommend • Service electric truck batteries in a well-ventilated Clark #1801146 Degreaser, or the equivalent to MS-180 area to avoid the danger of lighting explosive Freon TF Degreaser and Cleaner. Only approved solvents gases.
  • Page 19 Group SA, Safe Maintenance There are numerous variations in procedures, techniques, Improper or careless techniques cause accidents. Don’t tools and parts used for servicing industrial trucks, as well take chances with incorrect or damaged equipment. Read as in the skill of the person doing the work. and understand the procedures for safe operation and maintenance outlined in this manual.
  • Page 20 NOTE : Group SA, Safe Maintenance SM 765, Nov ’06...
  • Page 21 Group SA, Safe Maintenance Section 2 Lifting, Jacking, and Blocking Raising Drive Wheels ..........2 Chaning the Upright in Raised Position ....3 Raised Rear of Truck ..........3 Raised Entire Truck ..........4 Shipping Tie-Down Instructions ......5 WARNING Lifting or jacking any large piece of equipment such as a fork truck presents obvious hazards.
  • Page 22 Group SA, Safe Maintenance 5. Block the truck under the frame behind the drive CAUTION wheels with solid blocking. To perform these service procedures, first: 6. Turn key switch OFF. • Park truck on a level surface. 7. Check for safe clearance between drive wheels, •...
  • Page 23 Group SA, Safe Maintenance Chaining the Upright in Raised Position Raising Rear of Truck This procedure is used to safely provide clearance for The truck may be raised at the rear by jacking and block- access from the front of truck to components on or near ing under the center of the frame member at either the the drive axle.
  • Page 24 Group SA, Safe Maintenance Raising Entire Truck 4. Raise the truck only as high as necessary to perform the maintenance work. Refer to truck data plate for truck weights. 5. Put blocks at both sides of the truck, fully under the 1.
  • Page 25 Group SA, Safe Maintenance Shipping Tie-Down Instructions 5. Put blocks under the side frame, at each side of the jack. Spread the blocks close to the steer and drive 1. Front of Truck wheels for maximum stability. a. With Upright and Carriage Installed 6.
  • Page 26 NOTE : Group SA, Safe Maintenance SM 765, Nov ’06...
  • Page 27 Group SA, Safe Maintenance Section 3 Towing SM 765, Nov ’06 Towing • SA-3-1...
  • Page 28 280 ft-lb). These bolts are made of special, high-ten- sile steel and are not commercially available. When necessary, replace these bolt only with genuine Clark WARNING replacement parts. For your safety and the care of your truck, 5.
  • Page 29 Group SA, Safe Maintenance IMPORTANT WARNING Do not lift the disabled truck or any wheels Always engage the parking brake when park- off the floor while the truck is being towed. ing a lift truck. The truck can roll and cause injury or death to personnel near it.
  • Page 30 NOTE : Group SA, Safe Maintenance SM 765, Nov ’06...

  • Page 31: Periodic Service

    GROUP PS PERIODIC SERVICE GROUP PS PERIODIC SERVICE Maintenance Schedule ........Section 1 Planned Maintenance Program ...... Section 2 The PM Inspection Form ......... Section 3 SM 765, Nov ’06 Group PS PERIODIC SERVICE...
  • Page 32 NOTE : Group PS PERIODIC SERVICE SM 765, Nov ’06...

  • Page 33: Maintenance Schedule

    Group PS, Periodic Service Section 1. Maintenance Schedule “Periodic Service” and “Planned Maintenance” ......2 Determining Maintenance Intervals ..........2 GEX Service Chart/Lubrication Points ......... 3 Recommended Periodic Service Schedule ........4 SM 765, Nov ’06 Maintenance Schedule • PS-1-1...

  • Page 34: Periodic Service" And "Planned Maintenance

    The term “periodic service” includes all maintenance recorded on the hourmeter, and are based on experience tasks that should be performed on a regularly scheduled Clark has found to be convenient and suitable under nor- basis. mal operation. Standard operating condition classifica- tions are: The term “Planned Maintenance”...

  • Page 35: Gex Service Chart/Lubrication Points

    Group PS, Periodic Service GEX Service Chart/Lubrication Points SM 765, Nov ’06 Maintenance Schedule • PS-1-3...

  • Page 36: Recommended Periodic Service Schedule

    Group PS, Periodic Service Recommended Periodic Service Schedule This chart lists maintenance tasks that should be done periodically, the suggested time intervals, and the service manual Group in which the task is covered. Refer to Operator’s Manual for Daily Checks. Every Every Every...
  • Page 37 Group PS, Periodic Service TASKS Every Every Every 1st 50 Every 450- 500 Hours 900- 1000 Hours 2000 Hours Hours 50-250 Hours (or 3 months) (or 6 months) (or 1 year) Group 25/26 - Steer Axle and Lines Operation - check Power steering relief pressure - check Steer axle mounting - inspect Steer wheel and trunnion bearings -...
  • Page 38 NOTE : Group PS, Periodic Service SM 765, Nov ’06...

  • Page 39: Table Of Contents

    Group PS, Periodic Service Section 2 Planned Maintenance Use PM Report Form ............... 2 How to Perform the PM Periodic Inspections and Maintenance ..... 2 Visual Inspection ................2 Operational Checks ................ 5 Test Drive Truck with Load ............6 Lift Mechanism and Controls ............

  • Page 40: Use Pm Report Form

    As an aid in performing and documenting your PM inspections, Clark has prepared an Electric Truck Planned Maintenance Report form. Copies of this form may be obtained from your authorized Clark dealer. We recom- mend that you use this form as a checklist, to make a record of your inspection and truck condition.
  • Page 41 Group PS, Periodic Service tires, check the ground strap or chain for DANGER wear and secure attachment. Uprights can drop suddenly if not properly Check all of the critical components that handle or carry blocked. Look at the upright, but keep hands, the load.
  • Page 42 Check the fork stop pins (or bolt and washer) for secure condition. Wheels and Tires NOTE Your Clark dealer has special tools for mea- suring fork wear. WARNING If the fork blade at the heel is worn down by more than l0%, the load capacity is reduced and the fork must be replaced.

  • Page 43: Operational Checks

    Group PS, Periodic Service 2. Using the Display Seat Belt: At start up this symbol displays along with an audio alarm for 4 seconds. This display reminds you to fasten your seat belt. Parking Brake: The symbol is displayed and "- 255"...
  • Page 44 Group PS, Periodic Service Slow-speed indicator (Turtle shaped) • Release the control lever. It should return to neutral without binding. The pump motor should turn off. The traveling speed of truck is limited to The control lever should not bind when moving it set speed.

  • Page 45: Test Drive Truck With Load

    Group PS, Periodic Service • Drive the truck forward in a straight line at a high 2. Operaten the truck at a slow speed in a forward direc- tion of travel. Reverse direction of travel. The truck rate of speed. Listen for unusual drive train noise. should slow down to a smooth controlled stop, and Stop truck.

  • Page 46: Lift Mechanism And Controls

    Group PS, Periodic Service Test the service brake (drive motor cut-off) switch. Drive shifting from NEUTRAL to REVERSE, then back to the truck FORWARD (or in REVERSE) at creep speed. NEUTRAL. Check for positive control action when While holding the accelerator pedal steady in creep speed changing directions.
  • Page 47 Group PS, Periodic Service Test for correct tilt cylinder rod adjustment. Raise the car- WARNING riage to an intermediate position. Tilt the upright fully for- ward without a load on the forks. Check for upright FALLING FORKS. Do not walk or stand racking (twisting) as the tilt cylinders reach the end of under raised forks.

  • Page 48: Battery Compartment Inspection

    Look for cracks or worn areas in the wiring insulation. Check for loose con- nections at the control terminals. Air-clean as necessary. Treat the control panel plugs with Clark 1801145”Lectric- Like” Spray or Clark 1803827-brush on cleaner. Hydraulic Compartment Inspection Inspect condition of the battery connector and truck bat- tery receptacle.

  • Page 49: Cleaning

    Group PS, Periodic Service CLEANING Cleaning Summary * Battery Compartment. * Hydraulic Compartment * Drive Motor and Steer Motor. * Pump Motor. * Axle Mounting * Control Compartment * Upright. IMPORTANT Do not clean electrical components with steam. Only approved solvents should be used to clean Solid State components.

  • Page 50: Air-Cleaning

    Group PS, Periodic Service Air-Cleaning ponents which directly support, handle or control the load, or protect the operator. Always maintain a lift truck in a clean condition. Do not Check torque of critical items, including: overhead guard, allow dirt, dust, lint, or other contaminants to accumulate drive axle mounting, drive and steering wheel mounting, on the truck.

  • Page 51: Sump Tank Breather Maintenance

    Inspect the fill plug for damage. Replace as needed. Install Lift Chains and tighten the plug. Lubricate the entire length of the rail lift and carriage chains with Clark Chain and Cable Lube. SM 765, Nov ’06 Planned Maintenance • PS-2-13...
  • Page 52 Group PS, Periodic Service Air Cleaning of Motors tors by using a 10W~100W resistance connected from the +Batt(pos.) to the - Batt(neg.). WARNING Before inserting metal air cleaning wand, dis- connect the battery and discharge the capaci- PS-2-14 • Planned Maintenance SM 765, Nov ’06...
  • Page 53 As an aid to service technicians performing and • Use this form as a checklist, and make a record of documenting PM inspections, Clark has prepared your inspection and truck condition. Note the spe- an Electric Truck Planned Maintenance Report cial coding system for indicating the importance of form.
  • Page 54 Group PS, Periodic Service PS-3-2 • The PM Inspection Form SM 765, Oct ’06...
  • Page 55 GROUP 12 BATTERY GROUP 12 BATTERY Battery Service ..........Section 1 SM 765, Nov ’06 Group 12 BATTERY...
  • Page 56 NOTE : Group 12 BATTERY SM 765, Nov ’06...

  • Page 57: Battery Service

    Group 12, Battery Section 1 Battery Service Battery Handling ......................... 2 Battery Removal ........................... 3 Battery Maintenance ........................4 Maximum Battery Life ........................4 Battery Vents ..........................4 Battery Cleaning ..........................5 Battery Charging ..........................5 Battery Electrolyte.......................... 5 CleanBattery Compartment ......................

  • Page 58: Battery Handling

    Group 12, Battery Battery Handling DANGER Explosive gas is always present around bat- CAUTION teries, especially when they are being Remove all jewelry (watch, rings, bracelets, charged. etc.) before working on electrical systems. Severe burns can result from contact with •...

  • Page 59: Battery Removal

    Group 12, Battery Be sure the battery service area is equipped with material DANGER handling equipment designed for the purpose of removing and replacing batteries, such as a conveyer or overhead Never lay tools or other metal objects on a hoist equipped with safety hooks.

  • Page 60: Battery Maintenance

    Group 12, Battery 3. Lift and latch seat deck to access battery. age andcould ignite battery fumes, causing the bat- tery to explode. 4. If the battery to be handled is uncovered, cover bat- • Maintain good battery cable connections. tery with a non-conductive material (plywood, heavy cardboard, etc.) prior to removal from truck.

  • Page 61: Battery Cleaning

    Group 12, Battery Battery Cleaning Clean Battery Compartment The easiest and most satisfactory method of cleaning a . Using baking soda and water solution, clean the walls battery is to wash it with a low-pressure cold water spray. and floor of the compartment. Rinse with clear water. The battery top can also be washed with a baking soda .

  • Page 62: Keeping Battery Records

    Group 12, Battery Keeping Battery Records Battery Tests Records should be maintained to get the best service out NOTE of your battery and truck. Use both tests described here. These records should contain: Specific Gravity Test • Test Date. Each test should be dated for future ref- erence and comparison.
  • Page 63 GROUP 13 WIRING, SWITCHES, AND INSTRUMENTS GROUP 13 WIRING, SWITCHES, AND INSTRUMENTS Schematic Electric Circuit Diagrams ..... Section 1 General Electical Service Tips......Section 2 Wiring and Cables ........... Section 3 Switches and Sensors........Section 4 Instrument Panel ..........Section 5 SM 765, Nov ’06 Group 13 WIRING, SWITCHES, AND INSTRUMENTS...
  • Page 64 NOTE : Group 13 WIRING, SWITCHES, AND INSTRUMENTS SM 765, Nov ’06...
  • Page 65 Group 13, Wiring, Switches, and Instruments Section 1 Schematic Electric Circuit Diagrams Standard Truck ..........................IN-28280 ELH Options Truck ........................IN-28294 SM 765, Nov ’06 Schematic Electric Circuit Diagrams • 13-1-1...
  • Page 66 Group 13, Wiring, Switches, and Instruments Standard Truck 13-1-2 • Schematic Electric Circuit Diagrams SM 765, Nov ’06...
  • Page 67 Group 13, Wiring, Switches, and Instruments ELH Options Truck SM 765, Nov ’06 Schematic Electric Circuit Diagrams • 13-1-3...
  • Page 68 NOTE : Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06...
  • Page 69 Group 13, Wiring, Switches, and Instruments Section 2 General Electrical Service Tips General Electrical Service Tips • Make sure battery is disconnected. 3. Discharging Controller Capacitors CAUTION It is necessary to discharge the capacitors before you work Always wear safety glasses. on the controller.
  • Page 70 Group 13, Wiring, Switches, and Instruments Checking Power Cables Torquing Fasteners Every cable and wiring harness on this truck is manufac- Improperly torqued fasteners can cause damage tured to an exact specification. A shorter cable or harness Use an appropriate wrench and tighten all fasteners to the will not fit.
  • Page 71 Group 13, Wiring, Switches, and Instruments There is a moisture-resistant seal at each wireend of Multiple cable and wire connections must be con- the connector and between the plug and socket. nected as illustrated or electrical shorts and control damage may result. Check seals for damage that would make them unfit for furtherservice (cuts, etc.).
  • Page 72 NOTE : Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06...

  • Page 73: Wiring And Cables

    Group 13, Wiring, Switches, and Instruments Section 3 Wiring and Cables The following illustrations depict wiring and cable routing and connections for standard trucks and main accessory harness. Electrical Components ........................ SI-47116 Main Harness ..........................SI-47202 Cables............................. SI-47193 Accessory Harness and Components..................SI-47115 SM 765, Nov ’06 Wiring and Cables •...
  • Page 74 Group 13, Wiring, Switches, and Instruments Electrical Components 13-3-2 • Wiring and Cables SM 765, Nov ’06...
  • Page 75 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-3...
  • Page 76 Group 13, Wiring, Switches, and Instruments 13-3-4 • Wiring and Cables SM 765, Nov ’06...
  • Page 77 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-5...
  • Page 78 Group 13, Wiring, Switches, and Instruments 13-3-6 • Wiring and Cables SM 765, Nov ’06...
  • Page 79 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-7...
  • Page 80 Group 13, Wiring, Switches, and Instruments 13-3-8 • Wiring and Cables SM 765, Nov ’06...
  • Page 81 Group 13, Wiring, Switches, and Instruments Main Harness SM 765, Nov ’06 Wiring and Cables • 13-3-9...
  • Page 82 Group 13, Wiring, Switches, and Instruments 13-3-10 • Wiring and Cables SM 765, Nov ’06...
  • Page 83 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-11...
  • Page 84 Group 13, Wiring, Switches, and Instruments 13-3-12 • Wiring and Cables SM 765, Nov ’06...
  • Page 85 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-13...
  • Page 86 Group 13, Wiring, Switches, and Instruments Cables 13-3-14 • Wiring and Cables SM 765, Nov ’06...
  • Page 87 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-15...
  • Page 88 Group 13, Wiring, Switches, and Instruments 13-3-16 • Wiring and Cables SM 765, Nov ’06...
  • Page 89 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-17...
  • Page 90 Group 13, Wiring, Switches, and Instruments Accessory Harness and Components 13-3-18 • Wiring and Cables SM 765, Nov ’06...
  • Page 91 Group 13, Wiring, Switches, and Instruments SM 765, Nov ’06 Wiring and Cables • 13-3-19...
  • Page 92 Group 13, Wiring, Switches, and Instruments 13-3-20 • Wiring and Cables SM 765, Nov ’06...

  • Page 93: Switches And Sensors

    Group 13, Wiring, Switches, and Instruments Section 4 Switches and Sensors Accelerator Control Switch ....................2 Description ........................2 Adjustment........................2 Program Adjustment .....................3 Brake Switches........................3 Service Brake Switch Description ................3 Service Brake Switch Adjustment .................3 Parking Brake Switch Description ................4 Parking Brake Switch Adjustment ................4 Parking Brake Operation ....................4 Seat Switch ........................5 Lift and Tilt Pump Switches ....................5...

  • Page 94: Accelerator Control Switch

    Group 13, Wiring, Switches, and Instruments Accelerator Control Switch Description trical pulses to the motor, which in turn will supply more power to the drive train. The accelerator control is operated by the accelerator foot An internal spring returns the control to start position. The pedal to send a signal for power demand to the control.

  • Page 95: Program Adjustment

    Group 13, Wiring, Switches, and Instruments Program Adjustment • Display will show software version • Turn the key switch Off and remove the tester cord from the control CAUTION • Plug the dash display harness into the "B" plug of Before any adjustments are done, safely jack the control up the truck, block the drive wheels off the...

  • Page 96: Parking Brake Switch Description

    Group 13, Wiring, Switches, and Instruments Parking Brake Switch Description Parking Brake Operation The parking brake switch is mounted to the hood under of The operator applies the parking brake by pull up on a parking brake assembly. The brake handle center pin parking brake, which is then held by a ratchet.

  • Page 97: Seat Switch

    Group 13, Wiring, Switches, and Instruments Seat Switch Lift and Tilt Pump Switches The GEX trucks are equipped with a seat switch that sig- Description nals the control to cut the power when the operator leaves the seat. The pump control switches are mounted on brackets at the When the seat switch is open, a -01 fault code will be dis- valve spools and they are normally open.

  • Page 98: Lift Pot Adjustment

    Group 13, Wiring, Switches, and Instruments Lift Pot Adjustment • Display will read "CONFIG MENU' "SET MODEL" 1. Insure that the flag of the actuator is properly posi- • Press "ENTER" button tioned on the flat of the large nut. •...

  • Page 99: Instrument Panel

    Group 13, Wiring, Switches, and Instruments Section 5 Instrument Panel Dash Display SM 765, Sep ’06 Instrument Panel • 13-5-1...

  • Page 100: Dash Display

    Group 13, Wiring, Switches, and Instruments Dash Display The Dash Display provides the operator with an easily understandable, visual feedback of the status of the truck and its system components.. 05/8/10 [WED] 1. Fuel level Indication 8. Error LED 2. Slow-speed icon (Turtle shaped) 9.
  • Page 101 Group 13, Wiring, Switches, and Instruments max. speed. (In upper example, the limited max. Seat Belt: At start up this symbol displays speed is 2km/h) along with an audio alarm for 4 seconds. This display reminds you to fasten your seat belt. Hourmeter &...

  • Page 102: Mode Selection But- Ton

    Group 13, Wiring, Switches, and Instruments MODE SELECTION BUT- Right arrow button (Power selection button) • 6 mode selection buttons are 1.Pressing this button, it will move to right located on right side of LCD. menu. • Each button has specific function, 2.In normal operating condition, it will select/ and some have multiple functions.

  • Page 103: Electrical Motors

    GROUP 16 ELECTRICAL MOTORS GROUP 16 ELECTRICAL MOTORS Motor Specifications And Descriptions ..Section 1 Drive Motor Overhaul ........Section 2 Pump Motor Overhaul ........Section 3 SM 765, Nov ’06 Group 16 ELECTRICAL MOTORS...
  • Page 104 NOTE : Group 16 ELECTRICAL MOTORS SM 765, Nov ’06...

  • Page 105: Specifications

    Group 16, Electrical Motors Section 1 Motor Specifications and Descriptions Specifications Drive Motors Pump Motor Frame Size: 240 mm (9.449in) diameter Frame Size: 200 mm (7.874 in) diameter Internal Bearings: Sealed and lubricated with high tem- Internal Bearings: Sealed and lubricated with high tem- perature grease for the life of the bearing.

  • Page 106: Description And Location

    Group 16, Electrical Motors Description and Location The pump motor also has a built-in thermistor which con- stantly monitors the winding temperature and reports this The truck has three electric AC motors: information to the control (this sensor is not serviceable). Should it sense that the motor is approaching the tempera- •...

  • Page 107: Inspection Procedure

    Group 16, Electrical Motors Section 2 Drive Motor Overhaul Inspection Procedure 6. Remove the bolts securing the lower battery plate and tilt the plate back against the rear battery plate. Before performing these service procedures: 7. Remove all electrical cables from the motor. Tag •...

  • Page 108: Ball Bearings

    Group 16, Electrical Motors Terminal Block Terminal Block Mounting Bracket Screw Non-Drive End Frame O-Ring Stator Rotor Drive End Frame Wave washer Encoder Bearing Ball Bearing O-Ring Shaft Seal Ball Bearings Encoder Bearing Both ball bearings are maintenance free. If it becomes The encoder bearing is used to communicate the motor necessary to remove the bearings to repair the motor, they speed to the controller.
  • Page 109 Group 16, Electrical Motors Replacing Encoder Bearing • Insure that the encoder cables are installed cor- rectly and do not get pinched or touch the rotor. • Install the end housing carefully onto the encoder bearing and press it on with a steady pressure. The lead from the bearing must located in the notch in the housing frame.
  • Page 110 NOTE : Group 16, Electrical Motors SM 765, Nov ’06...
  • Page 111 Group 16, Electrical Motors Section 3 Pump Motor Overhaul Inspection Procedure 3. Have drain pan in place to catch axle oil. Remove the hydraulic pump from the motor (see group 29 for Before performing these service procedures: instructions). • Park truck safely. IMPORTANT •...
  • Page 112 Group 16, Electrical Motors Terminal Block Terminal Block Mounting Bracket Screw Non-Drive End Frame Stator O-Ring Rotor Wave Washer Encoder Drive End Frame Bearing Snap Ring Snap Ring Ball Bearing Shaft Seal Pump Motor Exploded View Ball Bearings Encoder Bearing The encoder bearing is used to communicate the motor speed to the controller.
  • Page 113 Group 16, Electrical Motors Replacing Encoder Bearing Motor Reassembly In general the encoder bearing should be replaced every • Press new encoder bearing on to rotor at the inner time the motor is disassembled. ring with a steady pressure. The inner ring of the bearing must to be pressed against the shaft shoul- der.
  • Page 114 NOTE : Group 16, Electrical Motors SM 765, Nov ’06...
  • Page 115 GROUP 17 ELECTRICAL CONTACTORS GROUP 17 ELECTRICAL CONTACTORS Contactors Specifications and Overhaul... Section 1 SM 765, Nov ’06 Group 17 ELECTRICAL CONTACTORS...
  • Page 116 NOTE : Group 17 ELECTRICAL CONTACTORS SM 765, Nov ’06...

  • Page 117: Removal And Replacement

    Group 17, Electrical Contactors Section 1 Contactors Specifications and Overhaul Specifications Removal and Replacement Standard Truck: One Drive Line Contactor, one Pump 1. Disconnect power cables from contactors. Move Line Contactor. Mounting Fastener Torque: 8-10 N.m (71- power cables out of the way. 88 in-lb).

  • Page 118: Tip Replacement

    Group 17, Electrical Contactors CONTACTOR INSPECTION AND binding and that tips are in correct orienta- tion and tips contact correct mating parts. TIP REPLACEMENT 1. Check armature and movable contacts for freedom of movement by depressing movable arm with a screw- driver or small rod.
  • Page 119 GROUP 19 MOTOR CONTROLS GROUP 19 MOTOR CONTROLS Description ............Section 1 Control Programming ........Section 2 Control troubleshooting ........Section 3 GEX Factory Control Settings ......Section 4 SM 765, Sep ’06 Group 19 MOTOR CONTROLS,...
  • Page 120 NOTE : Group 19 MOTOR CONTROLS, SM 765, Sep ’06...
  • Page 121 Group 19, Motor Controls Section 1 Description The CLARK GEX uses a Dual AC controller to control both drive motors and a single AC controller to control the single motor/pump combination which supplies flow to all hydraulic functions and steering.

  • Page 122: Operational Features

    Group 19, Motor Controls Operational Features Speed Limit Parameters MAX SPEED FORWARD and MAX SPEED Creep Speed BACKWARD allow for the adjustment maximum speed that the vehicle can travel in each direction. The maxi- Parameters THROTTLE X POINT and THROTTLE Y mum speed is adjustable from 0 Hz to 140 Hz in 1 Hz POINT control how the truck reacts when you first push increments.

  • Page 123: Protection Features

    1V added − Running microswitch is in closed position. This is a multifunctional tool used with the AC controls. The handset (Clark part #8033636) has a display and a key board for data entry. Low Battery Charge: When the battery charge is low, -66 Code, the maximum...
  • Page 124 Communications with CLARK Dash: The traction controller communicates by CANBUS to Steer Angle Transducer CLARK dash. The dash shows Battery State of charge, Hourmeter and fault code if a fault occurs. Angular position of steered wheels in transduced to an...
  • Page 125 Group 19, Motor Controls Steering Table The relationship between the two motors speed changes as a function of the steering angle. The steering angle information comes from the transducer (potentiometer). As the steer wheel is turned, the inside motor will slow and than finally reverse direction to help the truck turn sharply.
  • Page 126 Group 19, Motor Controls Description of Connectors - DualAC2(Power) CAN H High level CANBUS CANT H CANBUS termination output, 120 ohm internally connected to CAN_H. Connect to CAN_L_OUT to insert termination. CAN_POS Positive of CAN circuit; to be used in case of optoisolated CANBUS CAN_L_OUT Low level CANBUS: to be used as repetition for CAN_L line or to be connected to CANT_H to insert termination resistance...

  • Page 127: Encoder Installation

    Group 19, Motor Controls ENABLE Traction request input; active high. Pedal brake request input; active high. SR / HB Speed reduction or hand brake input; active low (micro switch open). PENC_L Positive of the left motor encoder power supply (+12V). NENC_L Negative of the left motor encoder power supply PHA_R...
  • Page 128 Group 19, Motor Controls The encoder power supply voltage and output electronic has to be communicated to ZAPI in order to correctly set the selection jumper in the controller. Description of Power Connections Negative of the battery Positive of the battery; if the power fuse is not present,positive cable coming from the Line contactor must be connected to this power connection...
  • Page 129 Group 19, Motor Controls Description of Connections - Hydraulic AC3 CPOT Accelerator potentiometer wiper. PPOT Potentiometer positive: 10V output; keep load > 1KW. NPOT Negative of accelerator unit, tested for wire disconnection diagnosis. Common of LIFT ENABLE / 1st SPEED / 2nd SPEED / 3rd SPEED / 4th SPEED / HYDRO / SR microswitches.
  • Page 130 Group 19, Motor Controls CAN-L-OUT Low level CAN-BUS voltage I/O. CAN-H High level CAN-BUS voltage I/O. CAN-H-OUT High level CAN-BUS voltage I/O. -BATT -Batt. MODE This input allows the customer to select the software for traction or lifting application. Configuration: MODE: Open (not connected) Traction inverter MODE: Close (connected with A5)

  • Page 131: Control Programming

    Description of Handset & Connections Digital Handsets used to communicate with the AC Controllers must be fitted with EPROM CK ULTRA, minimum "Release Number 3.07, CLARK part number 8033636. The Handset “Release Number” will be displayed on the Handset display momentarily when the key switch is first turned ON.
  • Page 132 The last 6 digits of the top line in the example above indicate the current software revision loaded into the Master control. The CK indicates CLARK and the 0.13 is the software revision level. The bottom line on the display indicates the Battery Voltage and the current level that has been set and the current internal hour meter reading of the control.
  • Page 133 Group 19, Motor Controls Gex Handset Master Control Configuration DA2M2BGCPE CK 0.13 DA2M2BGCPE CK 0.13 DISPLAY DISPLAY 80V 280A 00000 80V 280A 00000 KEYBOARD KEYBOARD HEADING Enter Main Menu Set Model Connected to 3 (Master), 4 (Slave), 5 (Pump) Enter Parameter Enter Acceleration Delay...
  • Page 134 Group 19, Motor Controls Master Control - "Dualac2 Power 80V" SUBMENU "SET OPTIONS" 1. HOUR COUNTER RUNNING: the counter registers any motor running. SEAT: the counter registers when the "key" is closed and operator is sitting on the seat. 2. BATTERY CHECK the battery discharge level check is carried out;...
  • Page 135 Group 19, Motor Controls SUBMENU "ADJUSTMENTS" 1. SET POT BRK MIN: Records the minimum value of the braking pedal potentiometer when the braking pedal (Not Used) switch is closed; the procedure is similar to the "Program VACC" function. This proce- dure is only used if the "pedal braking"...
  • Page 136 Group 19, Motor Controls 13. ADJUSTMENT #04: Determines the motor temperature level at which the "Motor Temperature" fault is (Do Not Change) signaled. The default temperature is 130° C. Icon on dash will illuminate at this temperature. 14. MOTOR SHUTDOWN: This parameter determines the motor temperature level at which the "Motor Shut- (Do Not Change) down"...
  • Page 137 Group 19, Motor Controls Parameter Regulation The following parameters can be modified( See Group 19, Section 4 for Clark factory recommended settings) 1. ACC DELAY: Determines the acceleration ramp 2. RELEASE BRAKING: Controls the deceleration ramp when the travel request (accelerator) is released The higher the setting, the more aggressive the braking.
  • Page 138 MAX SPEED REVERSE NOTE Maximum speed for the GEX20/30 can not exceed 140 Hz. Maximum speeds are adjustable from 0 Hz to 140 Hz in 1 Hz increments. Forward speed and reverse speeds can be set independently (Forward speed can be set to 8 MPH and Reverse speed can be set at 5MPH if desired) 19-2-8 •...

  • Page 139: Tester Menu

    Group 19, Motor Controls TESTER MENU The most important input or output signals can be measured in real time using the TESTER function of the handset. The handset acts as a multimeter able to read voltage, current and temperature. The following is a list of measurements for different configurations.
  • Page 140 Group 19, Motor Controls 15) ENABLE SWITCH: The level of the Enable digital input. ON /+BV = input active, switch closed. OFF / GND = input non-active, switch open. 16) SEAT SWITCH: The level of seat microswitch digital input. ON /+BV = input active, switch closed. OFF / GND = input non-active, switch open.
  • Page 141 Group 19, Motor Controls Slave Control - "Dualac2 Power (80V)" Submenu "Adjustments" 1. SET BATTERY TYPE: Selects nominal battery voltage 2. ADJUST BATTERY: Fine adjustment of the battery voltage measured by the controller. GEX Handset Slave Control Configuration DM2S2BGCPE CK 0.13 DISPLAY DM2S2BGCPE CK 0.13 80V 280A 00000...

  • Page 142: Slave Control

    Group 19, Motor Controls TESTER MENU The most important input or output signals can be measured in real time using the TESTER function of the handset. The handset acts as a multimeter able to read voltage, current and temperature. The following is a list of measurements for different configurations.

  • Page 143: Pump Control

    Group 19, Motor Controls PUMP CONTROL Using the configuration menu of the programming console, the user can configure the following functions. GEX Handset Pump Control Configuration AC3P2BIG CK0.09 AC3P2BIG CK0.09 DISPLAY DISPLAY 80V 450A 00000 80V 450A 00000 KEYBOARD KEYBOARD HEADING Enter Main Menu...
  • Page 144 Group 19, Motor Controls SUBMENU "SET OPTIONS" 1 HOUR METER TRUCK RUNNING: The meter registers when the "key" is ON KEY ON: The meter registers travel time only. 2 SET TEMPERATURE DIGITAL: A digital (ON/OFF) motor thermal sensor is connected to F6 input. ANALOG: An analog motor thermal sensor is connected to F6(the curve can be customized on customer request).
  • Page 145 Group 19, Motor Controls SUBMENU "ADJUSTMENTS" 1. SET BATTERY TYPE: Selects nominal battery voltage. 2. ADJUST BATTERY: Fine adjustment of battery voltage measured by the controller. 3. ADJUSTMENT #4: Used to decide the motor temp level on which the motor temp abnormal signal is dis- played.
  • Page 146 Group 19, Motor Controls Parameter Regulation: Pump Configuration The following parameters can be modified: 1. Acceleration Delay Acceleration ramp for lift(See Tables Below). 2. Deceleration Delay Deceleration ramp for lift(See Tables Below). 3. Acceleration Delay Tilt Acceleration ramp for tilt(See Tables Below). 4.
  • Page 147 Group 19, Motor Controls TESTER MENU The most important input or output signals can be measured in real time using the TESTER function of the handset. The handset acts as a multimeter able to read voltage, current and temperature. The following is a list of measurements for different configurations.
  • Page 148 Group 19, Motor Controls 12) AUX2 SPEED SWITCH: ON /+BV = input active, switch closed. OFF / GND = input non-active, switch open. 13) AUX3 SPEED SWITCH: ON /+BV = input active, switch closed. OFF / GND = input non-active, switch open. 14) HRYDRO SPEED REQ.: ON /+BV = input active, switch closed.
  • Page 149 Group 19, Motor Controls 6) Set the maximum steering angles, right and left; use the parameters in "Adjustment" menu. (See Group 13, Sec- tion 4 for programming procedures). 7) Verify “BATTERY VOLTAGE”. Use volt meter to determine voltage between +BT and -B on the controller. 8) Verify the "MAXIMUM CURRENT"...
  • Page 150 NOTE : Group 19, Motor Controls SM 765, Sep ’06...

  • Page 151: Control Troubleshooting

    Group 19, Motor Controls Section 3 CONTROL TROUBLESHOOTING FAULT CODES FOR GEX This is the list of codes that the CLARK dash display may show Fault Fault Name Control Fault Fault Name Control Code Code " HIGH TEMPERATURE" SLAVE "NO SEAT SWITCH"...

  • Page 152: Troubleshooting

    Group 19, Motor Controls Fault Code Charts Fault Action Fault Name Fault Description Control Troubleshooting Code Required "NO SEAT No input from seat MASTER • Controller detects the seat switch is open SWITCH" switch or SLAVE during operation. • Check seat switch wiring and connec- tions Repair seat •...
  • Page 153 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "LOGIC Failure in U,V,W MASTER • Fault in the hardware section of the logic Replace con- FAILURE #2 voltage feedback board that manages the phase 's voltage troller circuit feedback.
  • Page 154 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "VMN Wrong voltage on MASTER • This test is carried out during initial diag- HIGH" motor power out- nosis and in standby. Possible causes: puts; failure in the •...
  • Page 155 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "CAPACI- Power Capacitor • When key is switched on, the controller Voltage does not tries to charge the capacitors through a CHARGE" increase when the power resistor, and check if the capacitor key is turned ON;...
  • Page 156 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "DRIVER Line contactor coil MASTER • When the key is turned ON, the micro- SHORTED" driver is shorted processor checks that the line contactor coil driver is not shorted •...
  • Page 157 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "VACC NOT Warning: Accel- MASTER • This fault indicates that the accelerator OK" erator signal voltage is 1volt greater than the mini- (CPOT) voltage mum value programmed by PROGRAM higher than VACC function.
  • Page 158 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "ENCODER Motor speed sen- MASTER • This fault indicates that the frequency ERROR" sor (encoder) does supplied the motor is greater that 20 Hz, not work properly and the signal feedback from the encoder has a jump higher than 20 Hz in less than ten milliseconds.
  • Page 159 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "WATCH- Watchdog circuit SLAVE • It is a self-diagnosing test within the DOG" has been triggered logic between Master and Slave micro controllers. • This fault could also be caused by a Can- bus malfunction, which blinds Master - Slave communication.
  • Page 160 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "VMN Wrong voltage on SLAVE • This test is carried out during initial diag- Replace con- HIGH" motor power out- nosis and in standby. Possible causes: troller puts;...
  • Page 161 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "WATCH- Watchdog circuit PUMP • It is a self-diagnosing test within the DOG" has been triggered logic between Master and Slave micro controllers. This fault could also be caused by a CAN-BUS malfunction, which blinds Master -Slave communica- tion.
  • Page 162 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "VMN Wrong voltage on • This fault signals that the under voltage / LOW" motor power out- over voltage protection interrupt has puts; failure in the been triggered Two possible reasons: power section or •...
  • Page 163 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required “MOTOR Pump motor PUMP • After 15 seconds of the motor being LOCKED” locked up stalled with maximum current, controller reduces maximum current to 50%. • Check to see that the pump contactor is pulled in •...
  • Page 164 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "VACC NOT Warning: Accel- PUMP • This fault indicates that the accelerator OK" erator siganal voltage is 1volt greater than the mini- (CPOT) voltage mum value programmed by PROGRAM higher than VACC function.
  • Page 165 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "COIL Init: Line contac- PUMP • When the key is turned on, the micropro- SHORTED" tor and EB coil cessor checks that the line contactor coil driver protection driver short circuit protection hardware If circuit is damaged...
  • Page 166 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "MASTER Slave micro pro- SLAVE • Slave and Master microprocessor per- KO" cessor detects form a crosscheck in order to verify Master processor functionality. There are two conditions malfunctioning under which the slave enters this fault condition:...
  • Page 167 Group 19, Motor Controls Fault Action Fault Name Fault Description Control Troubleshooting Code Required "WRONG Battery voltage MASTER • This fault indicates that actual battery BAT- does not corre- voltage is 20% higher or 20% lower than TERY" spond to pro- "SET BATTERY"...
  • Page 168 NOTE : Group 19, Motor Controls SM 765, Dec ’06...
  • Page 169 19, Motor Controls Section 4 GEX Factory Control Settings Parameters in White are customer preference adjustable. Parameters in Orange are factory preset and not adjustable. Refer to Section 2 for Handset Programming Instructions Name Scaled Value Master (DUALAC2) PARAMETER CHANGE Turtle Mode Economic Mode Normal Mode...
  • Page 170 Group 19, Motor Controls PARAMETER CHANGE Turtle Mode Economic Mode Normal Mode Power Mode SET MODEL CONNECTED TO 3 (Master) 3 (Master) 3 (Master) 3 (Master) ADJUSTMENTS SET POT BRK MIN 0.5 V 0.5 V 0.5 V 0.5 V SET POT BRK MAX 4.5 V 4.5 V 4.5 V...
  • Page 171 Group 19, Motor Controls PARAMETER CHANGE Turtle Mode Economic Mode Normal Mode Power Mode ACCELER. DELAY LEVEL = 0 LEVEL = 0 LEVEL = 0 LEVEL = 0 DECELER. DELAY LEVEL = 0 LEVEL = 0 LEVEL = 0 LEVEL = 0 LEVEL = 0 LEVEL = 0 LEVEL = 0...
  • Page 172 Group 19, Motor Controls ** Not used software version CK 1.12 + higher NOTE All motors must be stopped before saving parameters. parameter may not be stored to EEPROM if motor is run- ning. 19-4-4 • GEX Factory Control Settings SM 765, Nov ’06...
  • Page 173 GROUP 20 DRIVE AXLE GROUP 20 DRIVE AXLE Specification and description of drive axle ..Section 1 Troubleshooting of wheel drive axle ....Section 2 General operation of drive axle ......Section 3 Disassembly and Reassembly of drive axle ...Section 4 Disassembly and Reassembly of axle end..Section 5 Adjustment ............Section 6 SM 765, Nov ’06 Group 20 DRIVE AXLE...
  • Page 174 NOTE : Group 20 DRIVE AXLE SM 765, Nov ’06...

  • Page 175: Specification And Description Of Drive Axle

    Group 20, Drive Axle Section 1 Specification and description of drive axle Specifications Torque specification General specification Boss bearing and plate housing socket bolt, tightening Reduction ratio : torque : (330 kgf.cm) 12T Speed Forward/Reverse 1 Brake piston and plate housing socket bolt, tightening Oil capacity 1.0 liter torque : (130 kgf.cm) 8T...
  • Page 176 Group 20, Drive Axle Drive axle As this drive axle is power transmission system that is installed to driving wheel for electric forklift, it includes service brake and parking brake systems. It transmits the rotating force from the driving motor to the drive shaft(01).

  • Page 177: Troubleshooting Of Wheel Drive Axle

    Group 20, Drive Axle Section 2 Troubleshooting of wheel drive axle Troubleshooting for wheel drive axle Maintenance period Following contents help to solve the problem of wheel • Replacement period of wheel drive axle oil: 1,000 drive axle that does not perform right functions. hours •...
  • Page 178 NOTE : Group 20, Drive Axle SM 765, Nov ’06...

  • Page 179: General Operation Of Drive Axle

    Group 20, Drive Axle Section 3 General operation of drive axle General operation Cleaning of part Following procedure shall be applied to disassembly, Do not use gasoline because it is very combustible. It is inspection, washing, repair, installation and assembly pro- also not safe to the working environment.
  • Page 180 Checking: Check the steel part if there is mark, deforma- When it needs to be replaced, use official product of tion or discoloration that is related to inappropriate lubri- CLARK to maintain the unit performance and extend the cating work, notch, and step or scratch. life.

  • Page 181: Disassembly And Reassembly Of Drive Axle

    Group 20, Drive Axle Section 4 Disassembly and Reassembly of drive axle Disassembly of drive axle ass'y Disassembly of service brake D-ring Cautions to disassemble the drive axle D-ring Drive shaft assembly Piston Stopper brake Return spring Mounting plate Socket bolt Spacer Service brake piston Driven gear...
  • Page 182 Group 20, Drive Axle Disassembly of bearing boss Disassembly of parking lever and drive shaft Thrust needle bearing Spacer (shim) Housing plate Bolt Needle roller bearing Bearing boss O-ring Plate housing Pin spring King brake pin O-ring Parking brake lever Disassembly of bearing boss Disassembly of parking brake lever and •...
  • Page 183 Group 20, Drive Axle Disassembly of master hinge, Disassembly of drive shaft ass'y brake fitting and plug Brake air bleeding port Bearing Gea(13T) Brake port Bearing Plug Drive shaft Level plug Bolt Snap ring Snap ring Master hinge • Remove the snap ring from the drive shaft. •...
  • Page 184 NOTE : Group 20, Drive Axle SM 765, Nov ’06...

  • Page 185: Disassembly And Reassembly Of Axle End

    Group 20, Drive Axle Section 5 Disassembly and Reassembly of axle end Disassembly of carrier and hub bear- NOTE Arrange all the parts under the order of dis- assembly. Pay attention to the parts and removal order when disassemble. Plant gear shaft Pin spring Record with irremovable pen if necessary Taper roller bearing...
  • Page 186 Group 20, Drive Axle Disassembly of axle end Disassembly of carrier shaft ass'y Taper roller bearing Spacer Housing final Taper roller bearing Oil seal Stud bolt Adaptor Stud bolt Lock nut O-ring Wheel cap Bolt Disassembly of wheel sub assembly Disassembly of carrier shaft ass'y •...
  • Page 187 Group 20, Drive Axle Section 6 Adjustment Preloading and adjustment of hub • Re-measure the assembly product with dial gauge. • When compare the measured value with gauge, if taper roller bearing the space is plus value based on the gap, insert Lock nut Lock nut spacer with small width and if it is minus value,...
  • Page 188 Group 20, Drive Axle • Tighten the bolt to prevent the looseness. • Install the jig for measurement to contact on the disc and plate housing surfaces. • Measure the preloading value with push-pull gauge as shown in the figure 16. •...

  • Page 189: Adjustment

    Group 20, Drive Axle Adjustment of thrust needle bear- • Record the value that the dial gauge shows. • Calculate the stage differences of drive axle and ing gap wheel, and set the gap of shaft direction. • Set the thrust needle bearing based on gap specifi- cation.
  • Page 190 NOTE : Group 20, Drive Axle SM 765, Nov ’06...

  • Page 191: Wheels And Tires

    GROUP 22 GROUP 22 WHEELS AND TIRES Wheels and Tires Specifications and Description ..........Section 1 Pneumatic Wheels and Tires ....Section 2 SM 765, Nov ’06 Group 22, Wheels and tires...
  • Page 192 NOTE : Group 22, Wheels and tires SM 765, Nov ’06...

  • Page 193: Specifications

    Pneumatic Drive and Steer Tire Inflation Pressure : WARNING Drive GEX20/25/30: 800 kPa (116psi) For your safety and the safety of others, before you do tire or rim maintenance or ser- Steer GEX20/25/30: 1000 kPa (145psi) vice, read the OSHA rules regarding owner responsibility.
  • Page 194 NOTE : Group 22, Wheels and Tires SM 765, Nov ’06...
  • Page 195 CLARK dealer. 3. Never operate a vehicle on only one tire of a dual 12.
  • Page 196 • Drive GEX20/25/30: 800 kPa (116psi) • Steer GEX20/25/30: 1000 kPa (145 psi) 3. Check all wheel lug nuts or bolts to be sure none are loose or missing. Have missing bolts replaced and CAUTION...
  • Page 197 Group 22, Wheels and Tires Inspection and Minor Repair 2. Loosen the five lug nuts on the wheel. Inspect pneumatic tires and wheels carefully for. 1. Low inflation pressure. 2. Damaged tires. Check tires for cuts and breaks. 3. Damaged wheels or loosening of the lock ring on multi-piece rims.
  • Page 198 5. Remove the rubber inner tube protector (flap). GEX20/25/30: 800 kPa (116psi) • Steer wheel pressure is GEX20/25/30: 1000 kPa (145 psi). WARNING If tires are not fully inflated, see “Adding Air Pressure To Mounted Wheel/Tire Assem- blies” and follow the procedures for adding air to the mounted tires.
  • Page 199 11. Clean the wheels. Remove rust and dirt. NOTE Clark dealers can supply the correct lubri- cant, which contains a rust inhibitor. SM 765, Nov ’06 Pneumatic Wheels and Tires • 22-2-5...
  • Page 200 Group 22, Wheels and Tires Tire Replacement and Wheel 5. Install the wheel wedge. Reassembly 1. Put the tube into the tire. 6. Put the side ring over the rim and install the lock ring as shown. IMPORTANT Install washer 22.123 on tube over valve stem before flap is installed, when specified.
  • Page 201 Group 22, Wheels and Tires Directional-Tread Single Drive Tires 9. Disconnect the air chuck. Use a mallet and hit the ring to make sure the ring is fully installed. • Tire arrow to point in the dirction of forward rota- tion.
  • Page 202 4. Continue to fill the tire to the correct air pressure reading of 3. Slowly turn the cylinder valve counterclockwise Drive tire GEX20/25/30: 800 kPa (116 psi). (CCW) to open position. Steer tire GEX20/25/30: 1000 kPa (145 psi) IMPORTANT Put equal pressure in both tires of a dual assembly.
  • Page 203 Group 22, Wheels and Tires Checking and Adjusting Tire Pressure 6. Turn the tank valve clockwise (CW) and close the valve. WARNING Before you add air pressure to the tire, make sure the lock ring is correctly positioned in the rim and wheel wedge. The lock ring can separate from the rim with enough force to cause injury or death.
  • Page 204 NOTE : Group 22, Wheels and Tires SM 765, Nov ’06...

  • Page 205: Brake System

    GROUP 23 GROUP 23 BRAKE SYSTEM Brake System Specifications and Description ..Section 1 Service Brake Troubleshooting ......Section 2 Brake Pedal Linkage & Adjustments ....Section 3 Brake Bleeding ............Section 4 Pedal and Master Cylinder Service ...... Section 5 Parking Brake Service ...........
  • Page 206 NOTE : Group 23, Brake system SM 765, Dec ’06...
  • Page 207 Group 23, Brake System Section 1 Brake System Specifications and Descriptions Specifications ............2 General Description ..........2 Service Brake Operation ........2 Park Brake Operation ........... 2 Service Requirements ..........2 SM 765, Nov ’06 Brake System Specifications and Descriptions • 23-1-1...

  • Page 208: Specifications

    Type: Wet disc brake a wheel cylinder. The wheel cylinder operates a shoe lin- ings to be contacted on drum. Fluid: Hydraulic fluid, RANDO HD32 or NUTO H32 in accordance with CLARK specification MS-68 Parking Brake Operation (CLARK #2776239) Pedal Freeplay: None Operate the brake by pulling the hand brake mounted on the battery hood.
  • Page 209 Group 23, Brake System Brake lever & Pedal Master Cylinder Return spring Brake Line to Master Cylinder SM 765, Nov ’06 Brake System Specifications and Descriptions • 23-1-3...
  • Page 210 NOTE : Group 23, Brake System SM 765, Nov ’06...

  • Page 211: Service Brake Troubleshooting

    Group 23, Brake System Section 2 Service Brake Troubleshooting Service Brake Troubleshooting ......2 SM 765, Sep ’06 Service Brake Troubleshooting • 23-2-1...
  • Page 212 Group 23, Brake System Service Brake Troubleshooting Causes/Corrective Condition Actions Brake pedal drops to floor ........................A C E Brake pedal spongy ..........................A B Brakes stick, drag excessively, make noise, or overheat ..............D E F Excessive effort required to apply brake ....................A E Causes/Corrective Actions A .

  • Page 213: Brake Pedal Linkage & Adjustments

    Group 23, Brake System Section 3 Brake Pedal Linkage & Adjustments Introduction ............2 Adjustment ............. 2 SM 765, Nov ’06 Brake Pedal Linkage & Adjustments • 23-3-1...
  • Page 214 Group 23, Brake System Introduction If you want to adjust the height of brake pedal, adjust the height as 25mm by use of stop bolts of brake pedal and The illustration shows the service brake linkage which then lock the nuts. links the brake pedal to the master cylinder.
  • Page 215 Group 23, Brake System SM 765, Nov ’06 Brake Pedal Linkage & Adjustments • 23-3-3...
  • Page 216 NOTE : Group 23, Brake System SM 765, Nov ’06...

  • Page 217: Brake Bleeding

    Hydraulic fluid, RANDO HD32 or • The brake master cylinder or wheel cylinders-or NUTO H32 lines between-have been leaking and/or have been in accordance with CLARK specification MS-68 repaired or replaced. (CLARK #2776239). • Troubleshooting otherwise indicates that air has 4.
  • Page 218 NOTE : Group 23, Brake System SM 765, Nov ’06...

  • Page 219: Pedal And Master Cylinder Service

    Group 23, Brake System Section 5 Pedal and Master Cylinder Service (Removal, Replacement, and Adjustment) SM 765, Nov ’06 Pedal and Master Cylinder Service (Removal, Replacement, and Adjustment) • 23-5-1...

  • Page 220: Free Play Adjustment

    Group 23, Brake System Components Disassembly Freeplay Adjustment Use Figures 1, 2, and 3 as guide to disassembly and When the brake pedal linkage is properly adjusted, brak- adjustment. ing should begin only after the pedal is depressed a certain distance, This is “Freeplay”...
  • Page 221 Group 23, Brake System Reservoir Brake Lever & Hose to Master Cylinder Pedal Master Cylinder Stop Screw Pedal Spring SM 765, Nov ’06 Pedal and Master Cylinder Service (Removal, Replacement, and Adjustment) • 23-5-3...
  • Page 222 NOTE : Group 23, Brake System SM 765, Nov ’06...

  • Page 223: Operation

    (177-210 lbf⋅in). 1. With the lever fully lower, upstop against tab on • Apply a thin coat of Clark lubricant, part bracket, adjust slack out of brake cables and tighten #1802155, to ratchet teeth and ball end of wire adjusting/locking nuts.

  • Page 224: Parking Brake Cable Removal And Installation

    Group 23, Brake System Parking Brake Cable Removal and 2. Remove the parking cable from the service brake assembly by first removing the brake shoes as Installation described in the “Brake Overhaul and Adjustment” Section of this Group. 1. Disconnect each parking brake cable from the ratchet assembly as shown in the illustration below.
  • Page 225 GROUP 25 GROUP 25 STEERING COLUMN AND GEAR Steering System Specifications and Description . Section 1 Steering System Troubleshooting ......Section 2 Steering Column Removal and Installation ..Section 3 Steering System Relief Pressure Check and Adjustment ............Section 4 Steering Gear Overhaul ........
  • Page 226 NOTE : Group 25, Steering Column and gear SM 765, Nov ’06...

  • Page 227: Specifications

    Group 25, Steering Column and Gear Section 1 Steering System Specifications and Description Specifications Description Steering System Type: Hydrostatic power steering with All truck models have a hydrostatic power steering sys- load sensing, dynamic signal neutral circuit. tem, which is supplied with oil pressure from the main hydraulic pump.
  • Page 228 Group 25, Steering Column and Gear The column tilt lock mechanism allows the operator to The cover can be removed for service to steering column adjust the steering column. The column tilt lever knob components. The entire column can be removed for ser- releases the adjustment setting and the column returns to vice or replacement.
  • Page 229 Group 25, Steering Column and Gear Section 2 Steering System Troubleshooting No steering Handwheel kickback • Hydraulic fluid level very low. • Check valve faulty (or not in system). • Air in hydraulic oil. Slow steering response • Steering column sections not connected properly. •...
  • Page 230 Group 25, Steering Column and Gear Constant noise from steering axle Low pressure at the steering gear • Loose or worn hub bearing cones. Adjust or • Refer to Group 26. replace hub bearing cones. Replace bearing cones and bearing cups as a set. Steer cylinder rod binding or sticking •...
  • Page 231 Group 25, Steering Column and Gear Section 3 Steering Column and Component Removal and Replacement Steering Column and Component Removal ........... 2 Key Switch Removal ...................2 Hand Wheel, Horn Contact Ring, and Directional Control Assembly Removal ....2 Column Tilt Lock Assembly Removal ..............2 Steering Gear and Lower Steering Column Removal.
  • Page 232 Group 25, Steering Column and Gear 1. Park truck on a hard, level, and solid switch and pull rear cover smoothly after removing surface, such as a concrete floor with no tilt lock leveler. gaps or breaks. 2. Put upright in vertical position and fully lower the forks or attachment.
  • Page 233 Group 25, Steering Column and Gear 2. Remove the four bolts securing the lower column 4. Remove 4 bolts secruing tilt assembly to frame. . shaft and steering gear to the bracket on the frame. Tilt Lock Assembly Mounting Screw Steering Gear 3.
  • Page 234 Group 25, Steering Column and Gear Steer Column and Component Replacement These steps cover the procedures for reinstallation of the steering column including the steering gear, the tilt lock assembly, directional control assembly, ignition switch, and steering hand wheel and horn. IMPORTANT IMPORTANT Make sure all parts are clean and dry before...

  • Page 235: Description And Operation

    Steering system relief pressure setting may be checked pressure is adjustable and should be checked if indicated using a Mico Quadrigage (Clark Part No. 1800106) or by troubleshooting. Use the gauge port on the pump to with a conventional pressure gauge, 0-20,700 kPa (0-3000 check steering relief pressure.
  • Page 236 Group 25, Steering Column and Gear 2. Clean the port opening and connect the pressure gauge (also cleaned) to the gauge port on the main pump. To increase To decrease b. Clockwise adjustment of the relief valve seat 3. Start the engine and let it warm up until it runs raises the pressure setting at which the valve smoothly.
  • Page 237 Group 25, Steering Column and Gear Section 5 Steering Gear Overhaul IMPORTANT Before removing any component for overhaul, make sure the correct repair parts, seals, and gasket sets are available. NOTE The following material does not show the load sensing port on the steering gear (steering control unit).
  • Page 238 Group 25, Steering Column and Gear Disassembly 5. Remove meter (gerotor). Be careful not to drop star (rotor). Cleanliness is extremely important when repairing a steer- ing gear. Work in a clean area. Before disconnecting lines, clean port area of unit thoroughly. Use a wire brush to remove foreign material and debris from around exterior joints of the unit.
  • Page 239 Group 25, Steering Column and Gear 12. Place assembly so shaft is horizontal. Rotate spool IMPORTANT and sleeve until pin is horizontal. Push spool and Do not bind spool and sleeve in housing. sleeve assembly forward with your thumbs just far Rotate spool and sleeve assembly slowly enough to free seal gland bushing from housing.

  • Page 240: Parts Inspection

    Group 25, Steering Column and Gear Parts Inspection 4. Lubricate check ball seat and seals thoroughly before installing seat in housing. When installing seat do not Inspect all parts for damage, cracks, broken parts, dam- twist or damage seals. Install check ball seat in hous- aged threads, corrosion or erosion of surfaces, worn spots, ing;...
  • Page 241 Group 25, Steering Column and Gear 8. Compress extended end of centering spring set and 13. Install two bearing races and the needle thrust bear- push into spool sleeve assembly withdrawing instal- ing in the order shown. lation tool at the same time. 9.
  • Page 242 Group 25, Steering Column and Gear 16. Install seal gland bushing over the spool end with a Meter (Gerotor) End twisting motion. Tap the bushing in place with a rub- 18. Clamp housing in vise, as shown. Clamp lightly on ber hammer.
  • Page 243 Group 25, Steering Column and Gear 21. Rotate spool and sleeve assembly until pin is parallel 24. Install drive spacer(s) when used, in meter. with port face. Install drive, making sure you engage drive with pin. IMPORTANT Failure to properly install drive and pin may 25.
  • Page 244 NOTE : Group 25, Steering Column and Gear SM 765, Dec ’06...

  • Page 245: Steering Axle

    GROUP 26 GROUP 26 STEERING AXLE Steering Axle Specifications and Description ..Section 1 Steering Wheel Bearing Maintenance and Adjustment ....... Section 2 Steering Axle Removal and Installation ....Section 3 Steering Axle Overhaul ......... Section 4 Steering Cylinder Removal and Installation ..Section 5 Steering Cylinder Overhaul ........
  • Page 246 NOTE : Group 26, Steering Axle SM 765, Dec ’06...

  • Page 247: Specifications

    59° maximum outside turning angle. Steer Cylinder Seals Leakage Check: Every 50-250 hours and each PM. Bearing Grease : Grade No. 2 EP multi-purpose grease, Clark Part MS-107C. Steer Axle Mounting Inspection: Every 50-250 hours and each PM. Fastener Torques Power Steering Relief Pressure Check: Every year or 2000 hours of operation.
  • Page 248 Group 26, Steer Axle Steer Axle Steering Link Silent Mount Torque: 335-409 N . m Steering Knuckle 247-301 Ib . ft Steer Axle and Mounting 26-1-2 • Steering Axle Specifications and Description SM 765, Dec ’06...

  • Page 249: Wheel Bearing Lubrication

    Group 26, Steer Axle Section 2 Steering Axle Wheel Bearing maintenance and Adjustment Wheel Bearing Check..........1 Wheel Bearing Lubrication ........1 Bearing Disassembly ..........2 Bearing Reassembly ..........3 Wheel Bearing Adjustment ........4 IMPORTANT Before removing any component for overhaul, make sure the correct repair parts, seals, and gasket sets are available.
  • Page 250 Group 26, Steer Axle Bearing Disassembly 2. Refer to the exploded view illustration of the wheel bearing assembly. Loosen and remove the hubcap 1. Be sure truck is parked and blocked up correctly and from wheel or hub. You may have to lightly tap hub safely to raise steer wheels off the floor.
  • Page 251 5. Carefully press or tap grease seal into place with Use Grade No. 2 EP multi-purpose grease, asoftfaced mallet until seal is seated in bottom of Clark MS-107C. bore. 6. Install hub or wheel on spindle. Be careful not to damage grease seal lip when moving the hub over the end of spindle and threads.

  • Page 252: Wheel Bearing Adjustment

    Group 26, Steer Axle 8. Install the outer wheel bearing after it has been Wheel Bearing Adjustment packed with grease. The steer wheel bearings are retained and adjusted by the wheel nut. NOTE You should clean and repack the wheel bear- ings before performing a wheel bearing adjustment.
  • Page 253 Group 26, Steer Axle Section 3 Steering Axle Removal and Replacement Steer Axle Removal ..........2 Steer Axle Replacement ........3 SM 765, Dec ’06 Steering Axle Removal and Replacement • 26-3-1...
  • Page 254 Group 26, Steer Axle CAUTION SAFE PARKING. Before working on truck: 1. Park truck on a hard, level, and solid surface, such as a concrete floor with no gaps or breaks. 2. Put upright in vertical position and fully lower the forks or attachment. 3.
  • Page 255 Group 26, Steer Axle 2. Make sure that the silent blocks are positioned cor- rectly front and rear on the steer axle trunnions at the Old Steer Axle start of installation. Align the silent blocks square with the axle. 3. Use a fork lift truck or mobile floor jack to tempo- rarily support and raise the axle into place under the Steer Axle truck.
  • Page 256 Group 26, Steer Axle 9. Carefully raise the truck off the blocking as described in “Lifting, Jacking and Blocking”. Remove the blocking and lower the truck to the floor. 10. If removed, reinstall countenveight; refer to Group 38, Section 2, “Counterweight Removal and Replacement”.
  • Page 257 Group 26, Steer Axle Section 4 Steering Axle Overhaul Preparation for Steer Axle Disassemble and Overhaul ..2 Steer Axle Disassembly ............2 Parts Inspection ..............3 Steer Axle Reassembly ............3 IMPORTANT Before removing any component for overhaul, make sure the correct repair parts, seals, and gasket sets are available.
  • Page 258 Group 26, Steer Axle Preparation For Steer Axle 2. Remove and discard cotter pin from kingpin castel- lated nut. Remove the nut. Disassembly and Over haul NOTE Kingpin castel- Cleanliness is of extreme importance in the lated Nut repair and overhaul of this assembly. •...
  • Page 259 Steer Axle Reassembly Kingpin Recommended greasing procedure: Retainer Pin a. Use Grade No. 2 EP multi-purpose grease, Clark 4. Reset the kingpin castellated nut to the top of the MS-107 or equivalent. kingpin. Torque nut to 50-60 N⋅m (36.5-44 ft-lb).
  • Page 260 NOTE : Group 26, Steer Axle SM 765, Dec ’06...
  • Page 261 Group 26, Steer Axle Section 5 Steering Cylinder Removal and Replacement CAUTION CAUTION CAUTION SAFE PARKING. Before working on truck: Steer Cylinder Rod Steering Link Pin 1. Park truck on a hard, level, and solid Steering Link 2. surface, such as a concrete floor with no gaps or breaks.
  • Page 262 Group 26, Steer Axle Cylinder is now ready to be removed from the steer axle body. Cylinder must be lifted off dowel pins positioning cylinder to axle body. CAUTION CAUTION CAUTION CAUTION CAUTION CAUTION Cylinder is somewhat heavy and bulky. Cylinder is somewhat heavy and bulky.
  • Page 263 Group 26, Steer Axle 3. Rotate steering link into cylinder rod end and align bearing hole with rod end. 4. Tap pin through steer link bearing hole with snap ring groove on lower end. IMPORTANT Make sure bearing is properly aligned with pin in the hole.
  • Page 264 NOTE : Group 26, Steer Axle SM 765, Dec ’06...
  • Page 265 Group 26, Steer Axle Section 6 Steer Cylinder Overhaul Preparation for Steer Cylinder Disassembly and Overhaul ........2 Steer Cylinder Disassembly ........2 Parts Inspection ............. 2 Steer Cylinder Reassembly ........3 Operational Pressure Test ........4 IMPORTANT Before removing any component for overhaul, make sure the correct repair parts, seals, and gasket sets are available.

  • Page 266: 26-6-2 • Steer Cylinder Overhaul

    Group 26, Steer Axle Preparation for Steer Cylinder Disas- 4. Remove gland from opposite end of steer cylinder. sembly and Over haul 5. Remove the seal and O-ring set from the piston. Dis- card seals. Replace with new seal set at assembly. Refer to Section 5 for removal of steer cylinder from the steer axle body.

  • Page 267: Steer Cylinder Reassembly

    Group 26, Steer Axle 5. Carefully inspect the cylinder internal bore for wear, scratches, corrosion or other damage. Check the out- side for damage. Inspect all welds for cracks. 6. Inspect the cylinder ports and threads to be sure they are free of contamination and that the threads are clean and not damaged.

  • Page 268: Operational Pressure Test

    Group 26, Steer Axle 6. Install the gland onto the cylinder bore rim, making Operational Pressure Test sure gland is fully seated on cylinder. Once cylinder is remounted on axle (see Section 5), con- 7. Install piston and rod assembly into the cylinder. nect pressure source in turn at each port.
  • Page 269 Group 26, Steer Axle Section 7 Pivot-Turn Steering Axle Maintenance Specifications ............2 Description ............... 2 Wheel Bearing Check..........4 Wheel Bearing Lubrication ........4 Wheel Bearing Adjustment ........7 Steer Axle Disassembly .......... 7 Part Inspection............9 Steer Axle Reassembly ........... 9 SM 765, Dec ’06 Pivot-Turn Steering Axle Maintenance •...

  • Page 270: Specifications

    75° maximum outside turning angle. Steer Cylinder Seals Leakage Check: Every 50-250 hours and each PM. Bearing Grease : Grade No. 2 EP multi-purpose grease, Clark Part MS-107C. Steer Axle Mounting Inspection: Every 50-250 hours and each PM. Fastener Torques Power Steering Relief Pressure Check: Every year or 2000 hours of operation.
  • Page 271 Group 26, Steer Axle Steer Axle Steering Link Silent Mount Steering Knuckle Steer Axle and Mounting SM 765, Dec ’06 Pivot-Turn Steering Axle Maintenance • 26-7-3...

  • Page 272: Wheel Bearing Check

    Group 26, Steer Axle Wheel Bearing Lubrication IMPORTANT Before removing any component for over- These procedures cover bearing lubrication for steer haul, make sure the correct repair parts, wheels used on the truck ; pneumatic-tire wheels which seals, and gasket sets are available. are mounted on a hub that contains the bearing compo- nents.
  • Page 273 Group 26, Steer Axle Bearing Disassembly a brass drift pin, rod, or piece of pipe to drive the bearing and seal out of the hub. 1. Be sure truck is parked and blocked up correctly and safely to raise steer wheels off the floor. Refer to “Lifting, Jacking, and Blocking,”...
  • Page 274 Use Grade No. 2 EP multi-purpose grease, 7. Pack cavity in hub between bearings one-half full Clark MS-107C. with grease. 1. Install new inner and outer bearing cups by pressing 8. Install the outer wheel bearing after it has been into hub or wheel.

  • Page 275: Wheel Bearing Adjustment

    Group 26, Steer Axle 16. Refit O-ring on hubcap and install hubcap by tapping 10. Recheck for correct bearing adjustment by rotating the wheel by hand. Wheel should rotate freely or into place with a rubber or plastic-faced hammer. with only slight “drag”. Readjust bearings by adjust- ing wheel nut as necessary to avoid binding in bear- ings.
  • Page 276 Group 26, Steer Axle To disassemble the steering knuckle, kingpin, and bearing 5. Remove the knuckle bearing washers, dust covers, from the steer axle, it is not necessary to remove the axle upper and lower grease seals and bearings from the from the truck.

  • Page 277: Steer Axle Reassembly

    Center Hole faces of parts with a light coating of engine oil. Steer Axle Reassembly Recommended greasing procedure: a. Use Grade No. 2 EP multi-purpose grease, Clark MS-107 or equivalent. b. Pack all tapered roller bearings with grease before assembly.
  • Page 278 Group 26, Steer Axle 8. Reinstall grease fitting in knuckle housing and lubri- cate with recommended grease. Knuckle Housing Grease fitting 26-7-10 • Pivot-Turn Steering Axle Maintenance SM 765, Dec ’06...
  • Page 279 GROUP 29 GROUP 29 HYDRAULIC SUMP, FILTERS, AND PUMP Main Hydraulic Sump, Filters, and Pump Specifications and Description ......Section 1 Main Hydraulic Pump Troubleshooting ....Section 2 Main Hydraulic Pump Removal and Installation Section 3 NOTE This group covers the main hydraulic pump for the load handling system.
  • Page 280 NOTE : Group 29, HYDRAULIC SUMP, FILTERS, AND PUMP SM 765, Nov ’06...
  • Page 281 Group 29, Hydraulic Sump, Filters, and Pump Section 1 Main Hydraulic Sump, Filters, and Pump Specifications and Description Specifications ............2 Service Intervals ..........2 System Description ..........2 Sump Tank Fill Levels .......... 4 Hydraulic Fluid and Filter Change ..... 5 Remove, clean and replace the strainer ....

  • Page 282: Specifications

    The hydraulic pump and motor assembly is mounted to Sump Capacity: Usable oil = 24 Litres (6.3 Gal) the flow plate. Hydraulic Fluid Type: Clark Hydraulic Fluid MS-68 (or The hydraulic pump draws oil from the sump and sends other specification MS-68).
  • Page 283 Group 29, Hydraulic Sump, Filters, and Pump Control Valve Filter Steering Gear Pump SM 765, Nov ’06 Main Hydraulic Sump, Filters, and Pump Specifications and Description • 29-1-3...

  • Page 284: Sump Tank Fill Levels

    Group 29, Hydraulic Sump, Filters, and Pump Sump Tank Fill Levels Pull out the dipstick for the hydraulic oil. 29-1-4 • Main Hydraulic Sump, Filters, and Pump Specifications and Description SM 765, Nov ’06...

  • Page 285: Hydraulic Fluid And Filter Change

    Group 29, Hydraulic Sump, Filters, and Pump Hydraulic Fluid and Filter Change Disconnect drain line from truck. NOTICE NOTICE CAUTION If old oil is excessively dirty or hydraulic sys- tem is contaminated, it is recommended that SAFE PARKING. Before working on truck: the sump tank be completely drained by 1.
  • Page 286 Filter Head Turn the key switch OFF. Filter Refill the sump tank with Clark MS-68 Hydraulic Fluid. Check truck operation. Turn key switch ON. Operate the hydraulic system. Cycle the lift system serval times: raise the lift carriage to full height and lower fully down. Check for leaks.
  • Page 287 Group 29, Hydraulic Sump, Filters, and Pump Section 2 Main Hydraulic Pump Troubleshooting Noisy Pump ............2 Pump Not Delivering Hydraulic Fluid ....2 Failure to Build Pressure ........2 Pump Not Developing Sufficient Pressure ..2 Pump Output Low ..........2 Foaming Fluid ............
  • Page 288 Group 29, Hydraulic Sump, Filters, and Pump Pump Not Developing Sufficient The following is a list of problems and solutions relating to the main hydraulic pump and associated components. Pressure For other hydraulic system troubleshooting, refer to Groups 30 and 34. •...

  • Page 289: External Leakage

    Group 29, Hydraulic Sump, Filters, and Pump External Leakage • Excessive system pressure; replace pressure con- trol valve on main hydraulic valve. • Faulty or distorted pump seal gasket; replace seal gasket. • Damaged surfaces on pump body or cover; correct and replace as required.
  • Page 290 NOTE : Group 29, Hydraulic Sump, Filters, and Pump SM 765, Nov ’06...
  • Page 291 Group 29, Hydraulic Sump, Filters, and Pump Section 3 Main Hydraulic Removal and Installation Main hydraulic Pump Removal ......2 Main Hydraulic Pump Installation ...... 3 SM 765, Sep ’06 Main Hydraulic Removal and Installation • 29-3-1...
  • Page 292 Group 29, Hydraulic Sump, Filters, and Pump Main Hydraulic Pump Removal NOTE NOTE Capacity of hydraulic sump is 24 L (6.3 gal). CAUTION 1. Place a drip pan under the hydraulic pump for oil that SAFE PARKING. Before working on truck: will drain from the pump and hoses when they are disconnected.

  • Page 293: Routine Maintenance

    See Section 1, Main Hydraulic Pressure Line Filters and Fluid Maintenance. Hydraulic 5. Refill sump as necessary using Clark Specification Pump MS-68 hydraulic fluid. See Section 1 for description Hydraulic Motor of sump tank fill levels.
  • Page 294 NOTE : Group 29, Hydraulic Sump, Filters, and Pump SM 765, Sep ’06...
  • Page 295 GROUP 30 GROUP 30 HYDRAULIC CONTROL VALVE/LIFT CIRCUIT Hydraulic Control Valve/Lift Circuit Specifications and Description ......Section 1 Hydraulic System Schematic ........ Section 2 Hydraulic System Troubleshooting ...... Section 3 Hydraulic System Pressure Checks and Adjustments ............ Section 4 Hydraulic Control Valve Removal and Replacement ............
  • Page 296 NOTE : Group 30, HYDRAULIC CONTROL VALVE/LIFT CIRCUIT SM 765, Sep ’06...

  • Page 297: Specifications

    Hydraulic Control Valve/Lift Circuit Specifications and Description Specifications Service Intervals Hydraulic Fluid Type: Clark specification MS-68 (Clark part #1802155 and #1800236) Hydraulic System Relief Pressure Check: Every year or Main Relief Valve Setting: 20.6 to 21.1 MPa (2988 to every 2000 hours of operation.
  • Page 298 Group 30, Hydraulic Control Valve/Lift Circuit Description moved. Excess oil flow is returned to the sump. A check valve prevents reverse flow. The following description focuses primarily on hydraulic When all the control valve spools are in neutral, the micro circuitry controlled by the main hydraulic control valve, switch turns the pump motor OFF and not fluid flows.

  • Page 299: Hydraulic Schematic

    Group 30, Hydraulic Control Valve/Lift Circuit Section 2 Hydraulic Schematic Hydraulic Circuit(For Normal Valve) SM 765, Nov ’06 Hydraulic Schematic • 30-2-1...
  • Page 300 Group 30, Hydraulic Control Valve/Lift Circuit Hydraulic Circuit(For ELH Valve) 30-2-2 • Hydraulic Schematic SM 765, Nov ’06...

  • Page 301: Hydraulic System Troubleshooting

    Group 30, Hydraulic Control Valve/Lift Circuit Section 3 Hydraulic System Troubleshooting The following is a list of problems and solutions relating • Cavitating pump; check hydraulic plumbing for to the main hydraulic control valve and associated compo- airtight hoses and connections. nents.
  • Page 302 Group 30, Hydraulic Control Valve/Lift Circuit Spring-centered spools do not return to No relief valve action (high pressure) neutral • Small particles of dirt in relief valve subassembly; check, clean, and/or replace relief valve, clean • Broken springs; rebuild valve. hole.
  • Page 303 Hydraulic system relief pressure setting may be checked using a Mica Quadrigage (Clark Part No. 923770) or with a conventional pressure gauge with suitable pressure range calibration. To cover all models of the truck, a gauge with capacity range of 0 to 34,475 kPa minimum (0 to 5000 psi) is recommended.
  • Page 304 Group 30, Hydraulic Control Valve/Lift Circuit Main Pressure Relief Adjustment Auxiliary Pressure Relief Adjustment IMPORTANT IMPORTANT Main pressure relief setting is set at the fac- The auxiliary relief setting only applies to a tory. If the relief pressure does not measure hydraulic valve that has auxiliary sections within the setting range, main pressure relief added.
  • Page 305 Group 30, Hydraulic Control Valve/Lift Circuit Flowrate per RPM GEX 30 Lift Tilt in GEX 20/25 Flowrate Speed velocity Remark deg/ Lift Tilt in Flowrate Speed velocity Remark 19.29 3.10 deg/ 23.63 3.80 23.39 3.76 11.6 27.97 4.50 11.8 28.45 4.57 13.4 32.31 5.19 14.0...
  • Page 306 NOTE : Group 30, Hydraulic Control Valve/Lift Circuit SM 765, Nov ’06...
  • Page 307 Group 30, Hydraulic Control Valve/Lift Circuit Section 5 Hydraulic Control Valve Removal and Replacement Hydraulic Control Valve Removal ...... 2 Preparation for Valve Removal .......2 Control Valve Linkage Disassembly ......2 Valve Removal............2 Hydraulic Control Valve Replacement ....3 Valve Replacement ..........

  • Page 308: Hydraulic Control Valve Removal

    Group 30, Hydraulic Control Valve/Lift Circuit Hydraulic Control Valve Removal Control Valve Linkage Disassembly Remove the cotter rings and clevis pins connecting the lift IMPORTANT and tilt (and auxiliary, as applicable) lever rods from the Keep all hydraulic ports, components, and hydraulic valve spools.

  • Page 309: Hydraulic Control Valve Replacement

    Group 30, Hydraulic Control Valve/Lift Circuit Hydraulic Control Valve Replacement Control Valve Linkage Reassembly 1. Insert the clevis pins through the rod-end clevises Valve Replacement and valve spools of the lift and tilt spools (and auxil- iary-lever rods and spools where applicable) and 1.

  • Page 310: Operational Checks

    Group 30, Hydraulic Control Valve/Lift Circuit Reinstall Valve Operational Checks 1. Operate the truck and hydraulic system. Check the 1. Reinstall valve and valve plumbing. system for leaks. Torque to WARNING Do not use your hands to check for hydraulic leakage.

  • Page 311: Tilt Cylinders

    GROUP 32 GROUP 32 TILT CYLINDERS Tilt Cylinder Specifications and Description ..Section 1 Checks and Adjustments ........Section 2 Tilt Cylinder Removal and Installation ....Section 3 Tilt Cylinder Overhaul .......... Section 4 IMPORTANT Other hydraulic-related components and curcuits are described and Illustrated in Group 25, “Steering Column and Gear”, Group 26 “Steer Axle”, Group 29, “Hydraulic Sump, Filters, and Pump”, Group 30, Hydraulic Control...
  • Page 312 NOTE : Group 32, tilt cylinders SM 765, Nov ’06...
  • Page 313 Group 32, Tilt Cylinders Section 1 Tilt Cylinder Specifications and Description Specifications Service Intervals See Group 30 for hydraulic system specifications. Tilt Cylinder Drift Test: Every 50-250 hours or each PM. Tilt Cylinder Type: Double-acting Tilt Cylinder Check and Adjustment: Every 50-250 hours or each PM.
  • Page 314 NOTE : Group 32, Tilt Cylinders SM 765, Nov ’06...
  • Page 315 Group 32, Tilt Cylinders Section 2 Tilt Cylinder Checks and Adjustments Tilt Cylinder Drift Test ......... 1 Drift Causes and Remedies........2 Tilt Cylinder Racking Check ........ 2 Forward Adjustment ..........2 Backward Adjustment ..........3 Tilt Flow Control Adjustments ......3 3.
  • Page 316 Group 32, Tilt Cylinders 5. Wait five minutes and measure and write down dis- tance between rod end and spacer. 6. The measurement must not exceed the following measures: Temperature Drift ° , 3.9mm @ 1 min ° ° C(122 °...
  • Page 317 Group 32, Tilt Cylinders NOTE NOTE NOTE NOTE NOTE 4. Use rod shims to fill in the space between the rod- end yoke and spacer. Screw rod back into yoke the Use wrench flat on rod under spacer (if same number of turns needed to remove. installed).
  • Page 318 NOTE : Group 32, Tilt Cylinders SM 765, Nov ’06...
  • Page 319 Group 32, Tilt Cylinders Section 3 Tilt Cylinder Removal and Replacement Tilt Cylinder Removal .......... . 2 Parts Inspection ............. 3 Tilt Cylinder Replacement ........3 SM 765, Nov ’06 Tilt Cylinder Removal and Replacement • 32-3-1...
  • Page 320 Group 32, Tilt Cylinders CAUTION WARNING SAFE PARKING. Before working on truck: The upright assembly is heavy. Use only hoists with enough capacity to lift the entire 1. Park truck on a hard, level,-and solid assembly. Keep hands and feet away from the surface, such as a concrete floor with no assembly.
  • Page 321 Group 32, Tilt Cylinders Tilt Cylinder Replacement 6. Remove lock-plate from tilt cylinder rod-end yoke. Use a soft drift and hammer to tap rod-end pin out of 1. Position tilt cylinder base yoke on frame mounting yoke. bracket. 7. Pop the cover from tilt cylinder base access port on 2.
  • Page 322 Group 32, Tilt Cylinders NOTE NOTE NOTE NOTE NOTE 6. Install tilt cylinder hydraulic lines. Check Group 40 for hydraulic fitting tightening procedures. O-rings If the rod-end yoke has been removed from of fittings should be lightly coated with clean the rod or loosened for adjustment, reinstall hydraulic fluid or compatible oil.
  • Page 323 Group 32, Tilt Cylinders Section 4 Tilt Cylinder Overhaul Preparation for Disassembly ....... . 2 Disassembly ............2 Inspection ............... 3 Reassembly .............. 3 IMPORTANT Before removing any component for overhaul, make sure the correct repair parts, seals, and gasket sets are available. 1 13 11 12 10 14 15 Typical Tilt Cylinder Cross section Tube Assy...

  • Page 324: Preparation For Disassembly

    Group 32, Tilt Cylinders Preparation For Disassembly 2. Carefully pull the rod, piston assembly, and gland from the cylinder barrel. Remove gland from rod. IMPORTANT Overhaul tilt cylinders only in a clean, dust- WARNING free location, using clean tools and equip- The use of compressed air to blow the piston ment.
  • Page 325 Group 32, Tilt Cylinders Inspection 2. Replace the piston packing and wearing. 1. Carefully clean all parts in an approved solvent and Piston Seal Wear Ring place on a clean surface. 2. Check the piston and rod for damage. Look for gouges, scratches, corrosion, or evidence of unusual wear.
  • Page 326 NOTE : Group 32, Tilt Cylinders SM 765, Nov ’06...
  • Page 327 GROUP 34 GROUP 34 UPRIGHTS Upright Specifications and Description ......Section 1 Troubleshooting ............... Section 2 Upringht Inspection ............Section 3 Carriage and Upright Roller Clearance Checks and Shim Adjustments ........Section 4 Cylinder Removal, Shimming, Overhaul, and Replacement ........... Section 5 Upright Chain Inspection, Adjustment, and Replacement ..............
  • Page 328 NOTE : Group 34, Uprights SM 765, Nov ’06...

  • Page 329: Upright Specifications And Description

    • Innerslide Lubricant (Clark P/N 886396) Load Back Rest: 215-264 N⋅m (159-195 ft-lb) • Chain and Cable Lube (Clark P/N 886399) Chain Anchor Bolt Jam Nut: 100-200 N⋅m (74-148 ft-lb) Carriage Side-Thrust Roller Bolts(External): 40-50 N⋅m Cylinder Types (29.5-37 ft-lb) Standard uprights use two lift cylinders.
  • Page 330 Group 34, Uprights Piston-type cylinders contain a by-pass check valve in the • Lift chain tension should be checked every 50-250 hours or monthly. piston that allows air and fluid that have accumulated in the rod end of the cylinder to return to the system. The •...
  • Page 331 Group 34, Uprights Upper Roller *Assembly of slider and adjustment of shim: Assemble the slider as the backside of rail and the friction surface of slider are in parallel. Match the outer rail end and inner rail end, and then make the gap between the flange face of inner rail and the slider will be within 0.5mm.
  • Page 332 Group 34, Uprights Upper Roller *Assembly of slider and adjustment of shim: Assemble the slider as the backside of rail and the friction surface of slider are in parallel. Match the outer rail end and inner rail end, and then make the gap between the flange face of inner rail and the slider will be within 0.5mm.
  • Page 333 Group 34, Uprights Typical Triple Stage Upringht-Overhead View Carriage Shim Roller Side thrust Roller Carriages and Roller Sets SM 765, Nov ’06 Upright Specifications and Description • 34-1-5...
  • Page 334 Group 34, Uprights 34-1-6 • Upright Specifications and Description SM 765, Nov ’06...
  • Page 335 Group 34, Uprights Four-Hose Adaptation for the Standard Upright Four-Hose Adaptation for the Triple-Stage Upright Four-Hose Adaptation for the Hi-Lo Upright SM 765, Nov ’06 Upright Specifications and Description • 34-1-7...
  • Page 336 NOTE : Group 34, Uprights SM 765, Nov ’06...

  • Page 337: Troubleshooting

    Group 34, Uprights Section 2 Troubleshooting The visual inspection and the operational checks pre- • Dry hose sheave or rollers; check condition of all sented in Section 3 should be used to determine problems sheaves and rollers and lubricate as necessary. with the upright.
  • Page 338 Group 34, Uprights Load cannot be lifted to maximum height • Defective priority valve; see Group 30 for valve troubleshooting information. • Hydraulic fluid level low, check level and fill. • Defective upright load-lowering flow valve; • Debris in upright; check and clean. remove valve clean, inspect, and replace if neces- sary.
  • Page 339 Group 34, Uprights • Internal leakage in primary lift cylinder; perform • Bent or broken carriage or inner rail; replace part - cylinder checks listed under “Load cannot be lifted do not try to repair by welding. to maximum height.” •...
  • Page 340 Group 34, Uprights • Gland static seals sealing surface damaged; check • Cylinder hydraulic fittings loose or worn; check grooves and bore. fitting O-rings, tighten fittings according to Group 40, “Hydraulic Fitting Tightening Procedure.” Oil leak at top of lift cylinder •...
  • Page 341 Group 34, Uprights Section 3 Upright Inspection CAUTION SAFE PARKING. Before working on truck: 1. Park truck on a hard, level, and solid sur- face, such as a concrete floor with no gaps or breaks. 2. Put upright in vertical position and fully lower the forks or attachment.
  • Page 342 Group 34, Uprights Basic Visual Inspection Lift Chains Use the following steps to conduct an initial visual inspec- Inspect the chains for: tion of the upright. This is the same type of inspection • Proper lubrication. The links should have a coat of operators should be conducting on a daily basis.

  • Page 343: Hydraulic System

    4. If the fork tips are not aligned within the specified 6mm (1/4in) difference, the cause of the problem Use of fork wear calipers are recommended (Clark part must be determined and corrected before returning number 1803641) to gauge fork wear as follows: the truck to service.

  • Page 344: Lift Chains

    Chain Wear (Stretch) - All Lift Chains reduce fork hanger life. Lift chain stretch due to wear in the joints can be mea- sured using a measuring tape or Clark’s chain check ruler. Chain Check Ruler - Clark Part Number 59-960-9908 •...
  • Page 345 Group 34, Uprights IMPORTANT WARNING Never replace a single chain in a set. Always Do not reach through the upright to push replace the two chains in a set for consistent chains for tension check. lift operation. Always replace anchor pins when replacing chains.
  • Page 346 Loctite can be the cause of binding and uneven operation. 271 (Clark Part 1802302). The internal thrust rollers use a jam nut to ensure that the bearing remains secure. 34-3-6 • Upright Inspection...
  • Page 347 Group 34, Uprights manufacturing tolerances and wear in the upright rail sec- WARNING tions. An upright or carriage can move unexpect- Side Clearance edly during service procedures causing Roller severe injury: Do not walk or stand under raised forks. Roller Shaft Keep clear of load and carriage when making and shoulder any check or adjustment.
  • Page 348 Group 34, Uprights Carriage rollers, including side-thrust rollers, and all NOTE upright rollers can be checked by examining roll patterns. The seals are installed with lubricant and a If irregular impressions result from the checks, perform trace amount will be in the gland/tube inter- the “Lift Cylinder Shimming Check”...

  • Page 349: Hydraulic Plumbing

    Group 34, Uprights If the upright does not increase lifting speed, but you still a. Hoses or tubes with scrapes or kinks should be suspect an internal leak, repeat the procedure with a replaced. capacity load. If the upright does not extend to full MFH, b.
  • Page 350 Group 34, Uprights Consider rebuilding the cylinders if the first two remedies WARNING in this list are not successful. See Section 5 for removal, overhaul, and replacement procedures for primary and Keep clear of load and carriage when making secondary cylinders. any checks or adjustments.

  • Page 351: Carriage And Upright Roller Clearance Checks And Shim Adjustments

    Group 34, Uprights Section 4 Carriage and Upright Roller Clearance Checks and Shim Adjustments IMPORTANT WARNING Before removing any component for over- Use an approved safety platform to reach the haul, make sure the correct repair parts and/ upper areas of the upright. Never use the or kits are available.
  • Page 352 Group 34, Uprights are canted (tilted) to allow the side face to bear properly tainty that the clearance is excessive, you perform the on the web. checks given below. Rail flange wear can cause excess play between the lift To correct excessive lift roller side clearance, you add rollers and the rail flange.
  • Page 353 Web Areas on Typical Rail Set 5. Repeats steps 2 through 4 for the widest span marked on the rail set. Spanner Tool. Clark Part #180109 SM 765, Nov ’06 Carriage and Upright Roller Clearance Checks and Shim Adjustments • 34-4-3...
  • Page 354 Group 34, Uprights Top Carriage Rollers and Internal Thrust Rollers 6. If the clearance at the widest rail set span is more than 2.25 mm (0.09 in), the roller set needs shim- The internal thrust rollers are nearly perpendicular to the ming.
  • Page 355 Group 34, Uprights Internal Thrust Roller Adjustment Upright Rollers 1. Remove the carriage as described in Section 7 of this The internal thrust rollers should be adjusted to extend 0- Group. 0.75 mm (0.03 in) into the top carriage roller side clear- ance.
  • Page 356 Group 34, Uprights Oversize Rollers 6. Move the clamp to the shimmed side and clamp the rollers against the shim and the rail web by position- At the time of roller shimming, ing the clamp between the top and middle carriage you may want to replace the lift rollers.
  • Page 357 Group 34, Uprights Upright Roller Removal • Replace any defective parts. 1. After the carriage has been removed, lower the 3. Add shims to the top and bottom rollers as deter- upright rails until both of the secondary (final) lift mined in the previous steps.
  • Page 358 Group 34, Uprights Roller Removal, Shimming, and Replacement 7. Disconnect the cylinder guide bolts. In Hi-Lo upright, disconnect the secondary cylinder To add shims to, or replace the rollers: hose. 1. Use a puller to remove the rollers from the posts. Or, gently pry the rollers off the posts.
  • Page 359 Group 34, Uprights Upright Reassembly 3. Reconnect the cylinder guide bolts. Do not tighten until inner and/or intermediate rails are in the fully The following steps detail the procedures for reassem- lowered position. Torque guide bolts nuts to 20-25 bling the upright. N⋅m (14.8-18.5 ft-lb).
  • Page 360 Group 34, Uprights Overshimming 7. Jack up the truck only enough to remove the blocking and slowly lower the truck so that its full weight is on Use these steps to check for overshimming: the floor. 1. With the forks removed, lift the upright to maximum 8.

  • Page 361: Cylinder Removal, Shimming, Overhaul, And Replacement

    Before removing any component for over- haul, make sure the correct repair parts, seals, and gasket sets are available. Upright Upright Type Number Cylinder Type <GEX20-30> Standard pneu V2324 Piston-Type Lift Cylinder pneu M2324 Piston-Type Secondary Cylin- Hi-Lo pneu H2317 Piston-Type Secondary Cylin- CAUTION CAUTION...
  • Page 362 Group 34, Uprights 3. Remove the cylinder rod retaining bolt. 2. Disconnect and cap the hydraulic line at the base of In Hi-Lo Upright, Remove the Cylinder Hose. the cylinder. Load Lowering Flow Valve 3. Remove and discard cotter pins from chain anchor 4.
  • Page 363 Group 34, Uprights 6. Disconnect cylinder mounting bolts and cylinder 4. Disconnect and cap the hydraulic line from the base base mounting bolts. of each cylinder. Remove the mounting bolts from the manifold block. 5. Lower the carriage Use these steps in reverse to replace the cylinder. Check Group 40 for hydraulic fitting tightening procedures.

  • Page 364: Cylinder Disassembly

    Group 34, Uprights 8. Disconnect the cylinder rod retaining bolts. 1. Clean the rod-end and gland thoroughly to prevent In Hi-Lo upright, Remove the cylinder hoses. contamination from falling into the cylinder during disassembly. 2. With a blunt punch or chisel, bend the lock ring out of the locking grooves of the gland.
  • Page 365 Take care when installing these parts to make sure that no parts are damaged. 1. Coat all packing, seals and rings in clean, hydraulic oil (Clark part number 1800236 qt., 1802155 gal.) prior to reassembly. Coat the inside of the gland nut bore with hydraulic oil.
  • Page 366 Group 34, Uprights 5. Insert the piston and rod into the cylinder. Be careful 8. Check the assembly by making sure the piston slides not to scratch or damage the cylinder gland nut freely in and out of the cylinder. threads.

  • Page 367: Upright Chain Inspection, Adjustment, And Replacement

    Group 34, Uprights Section 6 Upright Chain Inspection, Adjustment, and Replacement SM 765, Nov ’06 Upright Chain Inspection, Adjustment, and Replacement • 34-6-1...
  • Page 368 Group 34, Uprights Chain Configuration-Triple Stage Uprights 34-6-2 • Upright Chain Inspection, Adjustment, and Replacement SM 765, Nov ’06...

  • Page 369: Periodic Inspections

    Group 34, Uprights Periodic Inspections in this condition, a pin, or series of pins, can begin to twist out of a chain resulting in failure. The pin head rivets Each 50-250 hours of operation (more frequently in severe should be examined to determine if the "VEE" flats are or extreme environments), chains should be inspected and still in correct alignment.
  • Page 370 Chain Length Adjustments cracks will appear. These are similar in appearance to stress corrosion cracks. If a plated chain is required, consult Clark. Plated WARNING chains are assembled from modified, individually An upright or carriage can move unexpect-...
  • Page 371 Group 34, Uprights Standard Upright Chain Length Adjustment 3. Carriage stop-to-upright: a. Lift upright to its full height and check for clear- To adjust chain length on the standard upright use the fol- ance on the carriage safety stop. lowing illustration and procedures: b.
  • Page 372 Group 34, Uprights To adjust the cylinder lift chains on a TSU use the follow- IMPORTANT ing illustration and procedures: For all chain anchor adjustments: • Threaded chain anchors must be left free to pivot in mounting hole. • Anchor cotter pin heads must be to the inside of the upright.

  • Page 373: Chain Lubrication

    Group 34, Uprights Chain Lubrication Failure to follow these warnings can result in serious injury. See “Lifting, Jacking, and Like all bearing surfaces, the precision-manufactured, Blocking” for safe blocking procedures. hardened-steel, joint-wearing surfaces of leaf chain require a film of oil between all mating parts to prevent General Guidelines accelerated wear.
  • Page 374 Group 34, Uprights 4. Remove the chain anchor pins from the carriage on 2. Remove the chain anchor pins from the back of the the standard upright or the inner rail on the TSU. On primary cylinder. Pull the chains through the chain the TSU, the inner rails must be lowered to the floor sheave and lay over the carriage load backrest.

  • Page 375: Fork And Carriage Removal And Replacement

    Group 34, Uprights Section 7 Fork and Carriage Removal and Replacement 3. Lift tip of each fork and put a 100 x 100 mm (4 x 4 CAUTION CAUTION in) block under the fork arm near the heel. SAFE PARKING. Before working on truck: CAUTION CAUTION 1.
  • Page 376 Group 34, Uprights 4. Lift tips of forks to engage the fork hooks on the WARNING upper carriage fork bar. You may need to pull on the hoses/cables and 5. Remove blocks from under fork. chains while lowering the primary cylinder to 6.
  • Page 377 Group 34, Uprights 6. Disconnect the carriage chains at the base of the car- 10. Remove steer wheel blocks. Release the parking riage. Pull chains back off primary cylinder sheave. brake and slowly back the truck away from the car- riage.
  • Page 378 Group 34, Uprights 10. Reconnect the hoses and mounting strap to the car- WARNING riage auxiliary component if the carriage is so equipped. Never attempt to move or align the carriage or bearings by hand. Use a pry bar. 6. Lower the upright until the inner rail clears all of the carriage rollers.

  • Page 379: Upright Removal And Replacement

    Group 34, Uprights Section 8 Upright Removal and Replacement This Section describes how to remove the entire upright CAUTION CAUTION assembly from the truck. The carriage and forks must be removed from the upright assembly before the upright is SAFE PARKING. Before working on truck: removed.
  • Page 380 Group 34, Uprights Upright Removal 2. Disconnect and cap hydraulic line at the load-lower- ing flow valve. Secure the hose out of the way of the The following procedures are for uprights with carriage upright. and forks, or auxiliary components removed. See Section 7, “Fork and Carriage Removal and Replacement,”...
  • Page 381 Group 34, Uprights Upright Replacement 3. Remove tilt cylinder rod-end lock plates and rod-end pins from upright. 1. Use an overhead chain hoist of adequate capacity and an approved lift chain to lift upright into position. Tilt cylinder Rod end Tilt cylinder Mounting Tilt cylinder...
  • Page 382 Group 34, Uprights 2. Install rod end pins, lock plates, and fasteners. NOTE Tighten lock plate fasteners to a torque of 40-45 N⋅m Reconnect two-hose adapter assembly (30-33 ft-lb). hydraulic lines to the upright-mounted bracket. Tilt cylinder Rod end Tilt cylinder Mounting Tilt cylinder mounting Bolt...
  • Page 383 GROUP 38 GROUP 38 COUNTERWEIGHT AND CHASSIS Counterweight Specifications and Description ... Section 1 Counterweight Removal and Installation .... Section 2 Overhead Guard Removal and Installation ..Section 3 Floor Plate, Seat and Seat Deck Removal and Installation ............Section 4 SM 765, Dec ’06 Group 38, Counterweight and chassis...
  • Page 384 NOTE : Group 38, Counterweight and chassis SM 765, Dec ’06...
  • Page 385 Group 38, Counterweight and Chassis Section 1 Counterweight Specifications and Description Specifications ............2 Description ............. 2 General Maintenance ..........2 SM 765, Nov ’06 Counterweight Specifications and Description • 38-1-1...

  • Page 386: General Maintenance

    Counterweight weights(GEX): Short wheel base Long wheel base 28.2 BC 33.9 BC 560 kg (1235 lbs) GEX20 760 kg (1675 lbs) GEX25 720 kg (1587 lbs) GEX30 Generic Illustration 38-1-2 • Counterweight Specifications and Description SM 765, Nov ’06...
  • Page 387 Group 38, Counterweight and Chassis Section 2 Counterweight Removal and Installation Conterweight Removal .......... 2 Counterweight Installation ........3 SM 765, Nov ’06 Counterweight Removal and Installation • 38-2-1...

  • Page 388: Counterweight Removal

    Group 38, Counterweight and Chassis Counterweight Removal 4. Raise the hood of operator's seat, and remove the bat- tery 5. Install the eyebolt in the counterweight. The eyebolt CAUTION should bear 1193kg(2630lb). SAFE PARKING. Before working on truck: 6. Using an overhead hoist with sufficient lifting capac- 1.

  • Page 389: Counterweight Installation

    Counterweight Installation 2. Inspect the counterweight mounting bolts to make sure they are in good condition before installing. Use only Clark replacement parts. Torque the mounting WARNING bolts to 340-380 N⋅m (251-280 lb-ft). Stand clear of the counterweight as it is being hoisted, moved, or mounted.
  • Page 390 NOTE : Group 38, Counterweight Specifications and Description SM 765, Nov ’06...
  • Page 391 Group 38, Counterweight and Chassis Section 3 Overhead Guard Removal and Installation Overhead Guard Removal ........2 Overhead Guard Installation ....... 2 SM 765, Nov ’06 Overhead Guard Removal and Installation • 38-3-1...
  • Page 392 Group 38, Counterweight and Chassis Overhead Guard Installation CAUTION 1. Put overhead guard in place on the truck chassis. SAFE PARKING. Before working on truck: 2. Install the eight overhead guard mounting bolts. 1. Park truck on a hard, level and solid sur- face, such as a concrete floor with no Tighten to 88-95 N⋅m (65-70 lb-ft).
  • Page 393 Group 38, Counterweight and Chassis Section 4 Floor Plate, Seat and Seat Deck Removal and Installation Floor Plate Removal and Installation ....2 Operator’s Seat Deck Removal ......2 Operator’s Seat Deck Reinstallation ....3 SM 765, Nov ’06 Floor Plate, Seat and Seat Deck Removal and Installation • 38-4-1...
  • Page 394 Group 38, Counterweight and Chassis Operator's Seat Deck and Hood CAUTION Removal and Installation SAFE PARKING. Before working on truck: 1. Park truck on a hard, level and solid sur- Removal face, such as a concrete floor with no gaps or breaks. 1.
  • Page 395 Group 38, Counterweight and Chassis Seat Deck Seat deck mounting bolt Rear hood Gas spring Frame 4. Remove the hood mounting fasteners and remove the hood. Reinstallation. 1. Reinstall the hood in reverse order that it was removed. WARNING Failure to follow this reinstallation procedure may result in operator injury.
  • Page 396 NOTE : Group 38, Counterweight Specifications and Description SM 765, Nov ’06...
  • Page 397 GROUP 40 GROUP 40 SPECIFICATIONS Nameplate and Decals..........Section 1 General Specifications ........... Section 2 Hydraulic Fitting Tightening Procedure ..... Section 3 SM 765, Nov ’06 Group 40, SPECIFICATIONS...
  • Page 398 NOTE : Group 40, SPECIFICATIONS SM 765, Nov ’06...

  • Page 399: Nameplate And Decals

    Group 40, Specifications Section 1 Nameplate and Decals Nameplate and Decal Locations ......2 Nameplate and Decals .......... . 4 SM 765, Nov ’06 Nameplate and Decals • 40-1-1...
  • Page 400 TO PARK lift truck, operator must: • Completely lower forks or attachments. • Shift into neutral. • Turn off key. • Set parking brake. Clark Material Handling Co. Sit Down Rider 2798233 2372604 2372604 WARNING Read the...
  • Page 401 This section shows the nameplate (data and capacity 5. Truck weight - The approximate weight of the truck plate) and decals required to be on all operating Clark without a load on the forks. The truck weight plus the industrial trucks. The nameplate lists the data on the truck weight of the load must be considered when operat- - type and serial number - and the capacities of the truck.
  • Page 402 Turn off key. Shift into neutral. loads over Set parking brake. Turn off key. capacity on nameplate Clark Material Handling Co. Sit Down Rider 2798233 Set parking brake. unstable or Clark Material Handling Co. Sit Down Rider 2798233 high loads...
  • Page 403 Group 40, Specifications Hand Safety Warning Decal Battery Disconnect Warning Decal This safety decal is placed on the upright to warn of the This warning decal is located on the front of the seat deck. danger of injury from movement between rails, chains, It warns of the danger of truck movement when removing sheaves, fork carriage, and other parts of the upright or inserting the battery connector by calling for turning...
  • Page 404 Group 40, Specifications Electric Truck Warning Decal This warning decal is located on the inside of the electri- cal contactor compartment door. It warns that to prevent unexpected movement of the truck when working on it, to raise the drive wheels, disconnect the battery, discharge the capacitors and refer to maintenance procedures.

  • Page 405: General Specifications

    Group 40, Specifications Section 2 General Specifications Weights and Performance Specifications ..... 2 Critical Fastener Torque Specifications ....... 4 SM 765, Sep ’06 General Specifications • 40-2-1...
  • Page 406 Note: Rated capacity applies when using uprights with maximum fork height up to and including 3195 mm (126 in) For GEX 20-30 . Truck Weights and Axle Weights Approximate weights for standard trucks with 126” Standard upright and GEX20/25 28.2”, GEX30 33.9” comportment. Gross Vehicle Empty Vehicle...

  • Page 407: Brake System Specifications

    Counterweight Mounting Bolts (Bottom) Brake System Specifications Service Brake Type: Wet disc brake Fluid: Hydraulic fluid, RANDO HD32 or NUTO H32 in accordance with CLARK specification MS-68 (CLARK #2776239) Pedal Freeplay: None Parking Brake Type: Hand brake linked to service brake shoe at each wheel.
  • Page 408 Sump Type and Capacity: Removable tank mounted in truck side frame with maximum capacity of 25 L (6.6 gal- 3860(152)~4800(189) lons) 5210(199)~6100(240) 6370(251)~ Hydraulic Fluid Type: Clark Hydraulic Fluid specification QUAD MS-68. Hydraulic Fluid Filters: Return line filter and suction line Upright Specifications screen mounted in sump.
  • Page 409 Group 40, Specifications Section 3 Hydraulic Fitting Tightening Procedure 1. Tighten fitting finger tight until it stops turning, 2. Using finger tips only, lightly snug fitting with a while moving the fitting lightly side to side to pre- wrench until it bottoms out on the seat or port. Do vent cocking or thread damage.
  • Page 410 NOTE : Group 40, Specifications SM 765, Nov ’06...

This manual is also suitable for:

Gex30Gex25