1994–1998 Komatsu D31E-18, D31P-18, D31P-18A, D31PL-18, D31PLL-18, D31S-18, D31Q-18, D37E-2, D37P-2 Bulldozer & Crawler Loader Shop Manual (P/N SEBM01141805)

Komatsu shop manual SEBM01141805 covers the 1994–1998 D31-18 and D37-2 models listed above, including blade and bucket configurations, with service information for the 6D95L-1 and S6D95L-1 engines.

PDF Bookmarks and Wiring Detail

Search, navigation, and diagram detail: PDF text search is not available. Embedded bookmarks link to the main systems and many individual procedures; small wire codes and connector numbers in the wiring diagram require zooming.

The single printable, English-language PDF has 371 pages, including the cover, contents, and three-page revision list.

Hydroshift, Steering, and Work Equipment Service

These are selected workshop topics; the manual also includes component weight tables and coating-material application charts.

• Engine testing: Valve-clearance adjustment, fuel-injection timing, compression and blow-by measurements, plus cylinder-head and engine removal and installation.

• Cooling and fuel systems: Water-pump, radiator, thermostat, injection-pump, and nozzle-holder removal and installation, with fuel-circuit bleeding procedures.

• Powertrain repair: Step-by-step procedures for Hydroshift transmission disassembly and assembly, control-valve service, steering-clutch overhaul, and final-drive repair.

• Undercarriage: Track-frame, recoil-spring, idler, roller, and track-shoe removal and installation, with separate standards for dry and lubricated track links.

• Hydraulics and attachments: Relief-pressure testing, cylinder-drift diagnosis, hydraulic-cylinder service, and removal and installation of blades, buckets, and work equipment.

• Electrical reference: Wiring diagram, starting-switch connecting table, and wire-code classifications for conductor thickness, colors, and current ratings.

Written for service personnel performing workshop repairs, this manual uses hydraulic test equipment, lifting equipment, and component-specific service tools.

Engine Service and Its Scope

The cylinder-head installation section distinguishes head-bolt types and tightening methods by engine serial number. A valve arrangement chart supports valve-clearance adjustment, while the engine test tables separate the earlier and later D37 configurations.

Starting-motor and alternator removal and installation are covered, including their wiring, mounting brackets, and belt connections. Cooling-system procedures extend to the radiator guard, radiator, water pump, hoses, and thermostat.

For detailed engine work, the manual refers to the separate 95 Series Engine Shop Manual, which is not included in this PDF.

Powertrain Diagnosis and Internal Repair

Factory test specifications and fluid schematics give mechanics a basis for narrowing powertrain faults before deciding which assembly needs repair. For excessive shock when moving off or shifting, the troubleshooting chart identifies blocked orifices or faulty operation in the modulating relief and quick-return valves.

The power train hydraulic circuit diagrams, steering hydraulic circuit diagrams, and modulating graph explain oil routing and clutch-pressure buildup. Component sections cover steering control valves, booster cylinders, bevel gears, and the final drive, with bearing-preload, backlash, and tooth-contact adjustments.

The transmission disassembly notes address clutch-disc and plate storage because improper support can deform these parts.

Blade and Bucket Hydraulic Variants

The power angle and tiltdozer sections apply to D31E-18, D31P-18A, D37E-2, and D37P-2. D31P-18, D31PL-18, and D31PLL-18 use the straight tiltdozer sections; D31S-18 and D31Q-18 have separate bucket, lift-arm, and linkage coverage.

Hydraulic circuit diagrams distinguish the blade lift/tilt/angle controls from the bucket lift/dump controls. Troubleshooting charts cover weak lifting, slow movement, cylinder drift, and unstable blade or bucket operation.

Control-valve disassembly and assembly are documented for the different configurations. The suction safety valve instructions identify a test-stand requirement for resetting pressure after disassembly; hydraulic-cylinder assembly notes also flag possible damage to rod packings, dust seals, and O-rings during installation.

Working on heavy machinery involves inherent physical risks. Technicians must verify all pressure release protocols and system lockouts prior to beginning any maintenance task or complex repair.

Track and Recoil-Spring Work

Undercarriage maintenance standards distinguish track-link construction, pin and bushing fits, grouser wear, and roller inspection limits. Idler-cushion changes are assigned to specific machine serial ranges.

Recoil-spring disassembly and assembly specify compressor 791-685-8002 with a hydraulic pump and cylinder. The related illustrations show the different retaining arrangements.

Selected Relief-Pressure and Pedal-Travel Standards

At full throttle with the gearshift in neutral and transmission oil at 40–60°C, transmission main relief pressure is specified at 20–23 kg/cm² for earlier machines and 21–24 kg/cm² for the revised serial ranges listed above.

Steering main relief pressure is 18–20 kg/cm² at low idle, with transmission oil at 40–60°C, neutral gear selection, and the steering lever operated.

The inching-pedal travel standard is 103–113 mm, measured at the center of the pedal to the stroke end with the engine stopped.