1993 Clark GPX/DPX 30/35/40/40S/50/55 Forklift Service & Repair Manual Set (Manual No. SM 593)

The Clark sections cover the installed truck systems, while the embedded Perkins manuals provide internal engine repair procedures. Clark identifies the truck engines as the G4.236 gasoline/LPG and 1004.4 diesel; the broader Perkins engine-family coverage does not extend the forklift model list.

Repair coverage limits: IMPCO vaporizer-regulator internal overhaul is referred to separate supplements OH-373 and OH-354, which are not included. The power booster page identifies the assemblies and directs repairs to the appropriate kits rather than providing a detailed internal overhaul procedure.

PDF Search, Bookmarks and Drawing Detail

Search and diagram detail: An existing OCR text layer supports searches throughout the main service sections, although some illustration and form pages have little or no searchable body text. Embedded bookmarks cover the truck systems and engine chapters. Small wire numbers, relay terminals and harness labels on the checked diagrams require zooming for comfortable reading.

The download is one printable, English-language 602-page PDF containing the publications above. The total includes six cover/title pages, the original section dividers, inspection forms and appendices.

Powertrain, Steering and Lift-System Repairs

These selected service topics are supplemented by counterweight removal instructions and split-rim wheel handling procedures.

• Engine repair: Step-by-step removal and installation, cylinder-head work, piston and liner service, crankshaft inspection, timing-drive repair, and lubrication-system procedures.

• Transmission and drive axle: Hydratork stall and pressure checks, clutch-pack disassembly, transmission reassembly, axle-end overhaul, and differential backlash adjustment.

• Braking and inching: System troubleshooting, bleeding, pedal adjustment, master-cylinder overhaul, caliper inspection, piston replacement, and power booster component references.

• Steering: Char-Lynn control-unit troubleshooting and repair, steering-column removal, steer-axle overhaul, wheel-bearing adjustment, and steer-cylinder service.

• Hydraulic circuits: Vane-pump diagnosis and overhaul, sump and filter service, lift-valve pressure checks, hydraulic-valve repair, and tilt-cylinder overhaul.

• Uprights and carriage: Load and drift tests, roller-clearance checks, shim adjustment, lift-cylinder repair, chain inspection, and upright removal.

• Electrical checks: Wiring color codes, truck wiring and harness drawings, battery load tests, starting-circuit voltage-drop tests, and charging-system checks.

This material is for trained, authorized lift-truck service personnel; the engine repair sections assume normal workshop practices and suitable measuring and lifting equipment.

Engine, Fuel and Cooling Work

The engine chapters go beyond removal and replacement, with component exploded views, sectional drawings, wear limits and inspection dimensions for internal repairs. The diesel procedures identify special tools, including the MS.67B universal timing tool and PD.145D rear oil-seal installation tool.

Truck installation specifications and general Perkins engine data appear in separate sections. Their distinction matters when selecting fill quantities, tune-up settings or variant-specific procedures.

Fuel-system coverage includes gasoline carburetor disassembly and reassembly, velocity-governor overhaul, and IMPCO operating, maintenance and troubleshooting information. Vaporizer-regulator removal and installation are documented. The casting warnings explain why overtightened hose connections can crack the housing and cause leaks.

Cooling coverage includes troubleshooting, pressure and thermostat checks, fan-belt replacement and radiator removal.

Hydratork Diagnosis and Differential Setup

Stall-test indications and hydraulic pressure checks help distinguish engine-performance, converter and clutch-related symptoms before transmission teardown. The overhaul section follows the shafts, clutch assemblies, oil distributor and axle adapter through disassembly and reassembly.

Differential setup includes backlash and tooth-contact adjustment, supported by the Spiral Bevel and Hypoid Tooth Bearing Contact Chart.

Steering, Hydraulics and Upright Service

The Char-Lynn literature includes control-unit repair and troubleshooting charts. Its drawings do not illustrate the five-port unit, although the text discusses its additional load-sensing port.

Thermal shock is identified as a cause of temporary steering seizure and possible internal damage when hot hydraulic fluid reaches a relatively cool control unit. The Main Hydraulic System schematic connects the lift, tilt, steering and braking circuits for system diagnosis.

Upright procedures include carriage removal, roller shimming and cylinder holding tests. Follow the manual’s blocking, lifting and hydraulic-pressure precautions around raised uprights and heavy assemblies.

Electrical Drawings and Test References

The GPX30/50 D/LPG/GAS Wiring Diagram and GPX Harness drawing provide circuit and connection references alongside the electrical tests. These drawings support tracing starting, charging, instrument and warning circuits rather than relying on wire color alone.

Examples of Engine Fastener and Valve Data

For the G4.236, the engine manual lists 130 Nm for cylinder-head nuts and setscrews. Separate tables distinguish connecting-rod and main-bearing fasteners by engine serial break.

Clark’s 1004.4 diesel tune-up data specifies cold tappet clearances of 0.20 mm at the intake and 0.45 mm at the exhaust. These values illustrate the engine-specific adjustment data included alongside the repair procedures.