Clark GEX16/18/20s & GTX16/18/20s Forklift Service Manual – SM 795

Description

Clark GEX16/18/20s & GTX16/18/20s Forklift Service Manual – SM 795

This is the complete service manual for the Clark GEX16, GEX18, GEX20s four-wheel electric lift trucks and the GTX16, GTX18, GTX20s three-wheel electric lift trucks. Published under Book No. SM 795 (Part No. 8066413, Jun. 2008), the document runs through every major system on these trucks in the order a technician actually works on them, from safe lifting and jacking through to the last torque value in the specifications group.

File Details

• Manual type: Service / Workshop Manual
• Brand: Clark Material Handling Company
• Models covered: GEX16, GEX18, GEX20s (4 wheel); GTX16, GTX18, GTX20s (3 wheel)
• Book number: SM 795
• Part number: 8066413
• Publication date: June 2008
• Language: English
• Page count: 411 pages
• File format: PDF

Chapters Covered

• Group SA – Safe Maintenance
  • Safety signs and messages, safe maintenance practices
  • Lifting, jacking, and blocking the truck
  • Raising drive wheels, chaining the upright in raised position, raising rear of truck, raising entire truck
  • Shipping tie-down instructions and towing
• Group PS – Periodic Service
  • Maintenance schedules and determining maintenance intervals
  • GEX and GTX service charts / lubrication points
  • Planned Maintenance Program (external inspection, operational checks, internal inspection, air cleaning, minor adjustments, chassis lubrication, critical fastener torque checks)
  • The PM Inspection Form
• Group 12 – Battery
  • Battery handling, removal, maintenance, installation and records
  • Battery tests (specific gravity, load test) and connector installation
• Group 13 – Wiring, Switches, and Instruments
  • Schematic electric circuit diagrams (standard and optional truck)
  • General electrical service tips, checking power cables, torquing fasteners
  • Wiring and cables, switches and sensors
  • Instrument panel and dash display operation
• Group 16 – Electric Motors
  • Motor specifications and descriptions (drive motors, pump motor)
  • Drive motor overhaul, speed sensor service
  • Pump motor overhaul
• Group 17 – Contactors
  • Contactor specifications and overhaul
• Group 19 – Motor Controls
  • Description, operational features, protection features
  • Control programming with ZAPI handset
  • Control troubleshooting and fault codes
  • Factory control settings
• Group 20 – Drive Axle
  • Specifications and description of drive axle
  • Disassembly of drive axle and wheel assembly
  • Adjustment (bearing preload, brake clearance, thrust needle bearing clearance)
• Group 22 – Wheels and Tires
  • Specifications and description (solid and pneumatic)
  • Mounting and maintenance, cushion tire replacement
  • Pneumatic tire precautions, inspection and repair, wheel disassembly
• Group 23 – Brake System
  • Specifications and description, service brake troubleshooting
  • Brake pedal linkage and adjustments
  • Brake bleeding
  • Pedal and master cylinder service
  • Parking brake service
• Group 25 – Steering System (GEX16-20s)
  • Specifications and description, troubleshooting
  • Steering column removal and replacement
  • Steering system relief pressure check and adjustment
  • Steering axle wheel bearing maintenance and adjustment
  • Steering axle removal and replacement
  • Steer cylinder removal, replacement and overhaul
  • Steering gear overhaul
• Group 26 – Steer System (GTX16-20s)
  • Specifications and description, troubleshooting
  • Steering column removal and replacement
  • Steering system relief pressure check and adjustment
  • Steering gear overhaul (standard and ELH optional)
  • Steer axle service, steer angle sensor removal and replacement
• Group 29 – Hydraulic Sump, Filters, and Pump
  • Specifications and description, sump tank fill levels
  • Hydraulic fluid and filter change, strainer service
  • Main hydraulic pump troubleshooting
  • Main hydraulic pump removal and installation
• Group 30 – Hydraulic System
  • Hydraulic control valve / lift circuit specifications and description
  • Hydraulic system schematic (normal valve and ELH valve)
  • Hydraulic system troubleshooting
  • Hydraulic system pressure checks and adjustments
  • Hydraulic control valve removal and replacement
• Group 32 – Tilt Cylinders
  • Specifications and description, tilt ranges
  • Tilt cylinder drift check and racking check
  • Forward and backward adjustment
  • Tilt cylinder removal, replacement and overhaul
• Group 34 – Uprights
  • Specifications and description (standard, Hi-Lo, triple-stage)
  • Troubleshooting and upright inspection (basic and extended)
  • Carriage and upright roller clearance checks and shim adjustment
  • Cylinder removal, shimming, overhaul and replacement
  • Upright chain inspection, adjustment and replacement
  • Fork and carriage removal and replacement
  • Upright removal and replacement
• Group 38 – Counterweight and Chassis
  • Counterweight specifications, removal and installation
  • Overhead guard removal and installation
  • Floor plate, seat and seat deck removal and installation
• Group 40 – Specifications
  • Nameplates and decals
  • General specifications, weights and performance
  • Critical fastener torque specifications
  • Hydraulic fitting tightening procedure

What This Service Manual Gives You

The Clark GEX/GTX 16-20s service manual is organised the way these trucks are actually repaired: system by system, with the specification, the removal procedure, the overhaul procedure and the adjustment values grouped together so you are not jumping between documents. The opening Safe Maintenance group alone is worth having on hand, because it sets out the correct jacking and blocking methods for a counterbalanced electric truck, including the procedure for using the upright itself to raise the drive wheels, and the chain-in-place method that gives safe front access to the drive axle area.

The electrical side is covered in unusual depth for a manual of this era. Group 13 supplies full schematic circuit diagrams for both standard and optional trucks, plus connector PL/SO identification, harness tape-marker conventions and cable repair criteria. Group 16 breaks down the two identical AC traction motors and the single lift/steer pump motor with frame sizes, rotor and stator dimensions, air gaps, stall current and encoder pulse counts. Group 17 handles the line contactors, and Group 19 is effectively a controller manual on its own, covering the Dual AC traction control, the single ACE2 pump control, handset programming, the complete fault code list with troubleshooting actions, and the factory parameter settings for economy, normal, power and turtle modes.

On the mechanical side, the drive axle group includes the wet disc service brake and the planetary wheel drive, with the taper roller bearing preload setting, brake clearance measurement using a dial gauge and measurement jig, and the thrust needle bearing clearance shim calculation. The steering groups are split correctly by truck type, since the four-wheel GEX and three-wheel GTX use different steer arrangements, and both relief pressure check procedures are given with the correct gauge port and adjustment direction.

Hydraulics and the load handling side are covered from the sump through to the fork tips. Group 29 covers the sump, return line filter, suction screen and the gear-type pump; Group 30 gives the open-centre parallel-circuit control valve description, the hydraulic schematics, main and auxiliary relief pressure checks, and the flow rate per RPM chart for the 16/18/20s. Group 32 covers tilt cylinder drift and racking adjustment in both directions, and Group 34 covers upright inspection, roller shimming with the side clearance chart, cylinder shimming, chain stretch measurement and full upright removal.

Finally, Group 40 collects the numbers that matter: rated capacities, truck and axle weights, travel speeds, turning radii, lift and lowering speeds, tilt ranges, drift limits, and a critical fastener torque table covering drive axle mounting, wheel lug nuts, steering handwheel nut, tilt cylinder yoke clamps and counterweight bolts.

Who This Manual Suits

This is written for the technician working on a Clark electric counterbalance truck, not for an operator looking for a daily checklist. It assumes you have the truck on blocks, the battery disconnected, the capacitors discharged and the correct lifting equipment available. Fleet workshops running a mix of GEX and GTX 16, 18 and 20s machines will find the split steering groups and the shared electrical and hydraulic content cover all six models from one document. Independent repair shops taking on Clark electric trucks will find the controller fault code tables and the handset programming sequences particularly useful, because those are the areas where guesswork costs the most time.

Get Instant Access to the Clark GEX/GTX Service Manual

With the Clark GEX16/18/20s & GTX16/18/20s Forklift Service Manual – SM 795 on your screen, you can diagnose a fault code at the dash, program a replacement traction or pump controller, measure and reset brake clearance on the wet disc axle, reshim an upright roller set, adjust tilt cylinder racking, or pull a drive motor for bearing replacement, all using the procedures and figures Clark published for these trucks. Having the correct torque values, relief pressure settings and clearance limits to hand is what separates a repair that holds from one that comes back.

IMAGES PREVIEW

The manual is delivered as an instant PDF download after payment, with no shipping and no waiting. Read it on a laptop in the workshop, on a tablet next to the truck, or print just the pages you need for the job in front of you. Keep a copy on every device your service team uses.