2002–2005 Mitsubishi Forklift Trucks FGC15K-FGC30K & FG20-FG35A Service Manual (P/N 99719-70150)

• Publication set: Six Mitsubishi factory publications, 870 PDF pages: Chassis & Mast 99719-70150; 4G63/4G64 engine manuals 99729-74120 and 99729-14110; LP-gas and EPA fuel-system supplements 99729-75100 and 99729-75110; and Options Supplement 99739-91100.
• FGC chassis coverage: FGC15K/FGC18K: AF81C/AF81D/AF81E-00011-up; FGC20K/FGC25K: AF82C/AF82D/AF82E-00011-up; FGC20K HO/FGC25K HO: AF82C/AF82D/AF82E-90011-up; FGC30K: AF83C/AF83D/AF83E-00011-up.
• Drivetrain and running gear repair: Covers power-train and engine removal, torque converter and powershift transmission service, clutch-pack and control-valve work, pressure and stall testing, front reduction differential setup, rear axle and steering-cylinder repair, brake bleeding, and steering-gear overhaul.
• Hydraulic and mast repair: Details the hydraulic pump, tank, control valve, flow regulator, lift and tilt cylinders, cylinder-drift testing, plus removal, disassembly, reassembly, roller and mast-strip setup, chain adjustment, and lift-cylinder checks for simplex, duplex, and triplex masts.
• 4G63/4G64 engine and fuel variants: Includes removed-engine repair for the timing system, cylinder head and valves, camshaft and rocker gear, pistons, crankshaft, cylinder block, lubrication and cooling, carburetor, governor, starter, alternator, and distributor. Separate LP-gas sections distinguish D- and E-suffix chassis systems.
• Electrical and electronic diagnostics: Includes the console box, combination meter, anti-restart starter switch, lighting and fuse circuits, chassis electrical schematic, Spectrum LPG DTC charts, MIL/OBD checks, laptop data-stream and graphing procedures, connector views, and on-vehicle harness repair.
• Factory option installations: For the listed C-series chassis ranges, the options supplement covers rear combination and work lamps, warning strobe, reverse buzzer, mirror, auxiliary oil-filter, enclosed alternator, axle breather, wide/semi-wide axle, dual-element air-cleaner, and dust-indicator kits.

Coverage and Publication Structure

The core 99719-70150 chassis and mast publication is written for Mitsubishi 1-ton through 3-ton internal-combustion cushion-tire trucks. It handles truck-side work and directs engine repairs to the companion 4G63/4G64 publications. The engine books describe service with the engine removed; chassis-level engine removal, installation, and power-train access remain in the chassis manual.

The coverage is split across publications. Publication 99729-74120 covers the 4G63 and 4G64 base engine in the AA0001-ZZ9999-up range for both gasoline and LP-gas versions used with the FGC K-series material. Publication 99729-14110 is a separate 4G63/4G64 engine manual for FG20, FG25, FG30, and FG35A, PA3487-up. It does not add FG20-FG35A chassis, mast, transmission, axle, or hydraulic repair coverage to 99719-70150.

LP-gas coverage is serial-specific. The chassis manual assigns 99729-75100 to trucks with a D in the chassis serial number and 99729-75110 to E-suffix trucks. The D-series supplement covers the conventional tank, vacuum fuel lock, converter/vaporizer, mixer/carburetor, leak testing, adjustment, and CARB Tier 1 S-15G system used for 2001-2002 model-year applications. The E-series EPA supplement covers the 2004-system architecture with ECM control, drive-by-wire throttle, low-pressure regulator, fuel and pressure trim valves, TMAP, heated oxygen sensor, catalytic muffler, crank timing input, and closed-loop fuel control. The options publication is limited to the AF81C, AF82C, and AF83C ranges shown on its cover.

Factory Repair and Diagnostic Content

Transmission coverage goes well beyond removal. It includes torque-converter and transmission disassembly, input/output/idler shaft work, clutch plates and return springs, control-valve service, hydraulic pressure diagnosis, inching-pedal adjustment, clutch-valve testing, stall-speed checks, and an acceleration test. Axle chapters add bearing preload, reduction-gear backlash, face runout, and tooth-contact setup. Brake chapters cover the master cylinder, wheel brakes and cylinders, automatic-adjuster testing, manual adjustment, fluid-line bleeding, and final brake testing.

Hydraulic sections document pump and control-valve repair, lift- and tilt-cylinder disassembly, flow-regulator inspection, relief-pressure testing, and cylinder-drift diagnosis. Mast content is configuration-specific, with repair procedures for 3A15B/3A25B/3A30B simplex, 3B15C/3B25C/3B30C duplex, and 3C15C/3C25C/3C30C triplex assemblies. It includes lift-bracket and mast-roller selection, shim placement, mast-strip clearance, chain tension, fork inspection, tilt-angle adjustment, and lift-cylinder stroke checks.

Representative visual references include the Transmission Hydraulic Circuit, chassis Electrical Schematic, Schematic of Hydraulic System, simplex/duplex/triplex mast assembly views, S-15G Fuel System Wiring Schematic, and Closed Loop Control Schematic with connector and pin-location views. Service-data sections add component-specific torque tables, pressure-test specifications, capacities and approved fluids, wear limits, clearances, maintenance charts, component weights, and inspection guides.

Special-tool references include the 91268-07100 transmission clutch piston tool, 64309-17701 pressure gauge kit with 91268-00400 connector, control-valve pressure adapters 64309-16300/F4540-06300, engine oil-pan remover MD998727, and piston-pin setting tool MD998780. The EPA fuel supplement also calls out a hand-held diagnostic scanner and the ITK-1 fuel-pressure test kit.

Manual-Specific Service Notes

The transmission section calls for the correct clutch-plate combination and requires the thrust washer oil groove to face the gear; incorrect assembly can disrupt clutch operation and lubrication. When a reduction differential is reassembled, the original pinion shim must be reused or tooth contact will be incorrect, risking damage to the bevel-gear set. Hydraulic control-valve housings and spools are matched parts, and uneven tie-bolt tightening can distort the housing and cause sluggish spool movement.

Service work involves raised masts, heavy power-train assemblies, pressurized hydraulic and brake systems, LPG, hot components, and electrical circuits. Lower or securely block the forks and mast, relieve system and fuel pressure, isolate the battery where specified, and use rated lifting equipment and protective equipment. Repair work should be performed by qualified personnel using the complete manual section for the applicable serial and system.