Komatsu D61EX-12, D61PX-12 Bulldozer Shop Manual – 2002 (P/N SEBM018904)

Komatsu shop manual P/N SEBM018904, printed in Japan in December 2002, covers the D61EX-12 and D61PX-12 crawler tractor chassis, serial 1001 and up and B1001 and up.

PDF Search, Bookmarks, and Download Contents

Finding procedures and diagram details: Searchable text and embedded bookmarks support navigation through the workshop chapters. Some diagram labels are outside the searchable text layer. Small wiring labels require zooming.

The ZIP download contains one printable, English-language 678-page PDF, including the cover, three revision-list pages, five blank pages, and one revision-request form.

Power Train, HSS, and Undercarriage Repair

The following selected coverage highlights are not a complete contents list. Additional topics include radiator and hydraulic-oil-cooler replacement, ROPS-canopy removal, and dashboard service.

• Power train: Step-by-step removal, installation, disassembly, inspection, and assembly procedures for the PTO, torque converter, Torqflow transmission, and transmission control valve.

• Steering and brakes: HSS unit and motor service, steering-brake repair, brake-valve work, and steering-brake performance checks.

• Hydraulic testing: Power-train, work-equipment, steering, and control-circuit pressure checks, PPC adjustment and output testing, HSS leakage measurement, and cylinder bleeding.

• Undercarriage: Track-frame and recoil-spring service, idler and roller overhaul, lubricated-track rebuilding, one-link field repair, pivot-shaft work, and equalizer-bar bushing replacement.

• Work equipment: Blade-cylinder repair, main-control-valve and steering-PPC-valve procedures, suction-valve replacement, and blade/work-equipment removal and assembly.

• Fault diagnosis: Electrical, hydraulic/mechanical, and machine-monitor troubleshooting, supported by connector locations, pin-arrangement views, symptom flow diagrams, and serial-specific circuits.

Written for service-workshop personnel, this manual suits technicians with hydraulic diagnostic equipment and the lifting, pressing, and special tooling required for component overhaul.

Serial-Specific Chassis Coverage

Earlier sections distinguish machines 1001–1173 / B1001–B3000 from B3001 and up, including the S6D114E-1A and SA6D114E-2 engine installations. Changes affect hydraulic/HSS pump material, PPC and main-control-valve layouts, HSS components, and hydraulic and electrical schematics. That separation helps a technician select the correct system view and repair section before ordering parts or connecting test equipment.

Angle-tiltdozer, semi-U dozer, straight-tiltdozer, ripper, cab, ROPS-cab, and canopy arrangements are identified where they affect components, piping, controls, or diagrams.

Engine scope: Coverage includes engine removal and installation plus chassis-side checks of blow-by pressure, exhaust color, oil pressure, engine speed, belt tension, and torque-converter stall speed. Internal engine rebuilding requires the corresponding engine volume; this is the chassis volume.

Pressure Testing and Fault Isolation

The testing section pairs engine, chassis, and electrical standard-value tables with measuring points and diagnostic tools. Separate adjustments address fuel-control, forward/reverse, gearshift, parking-brake, brake-pedal, work-equipment-lock, straight-tiltdozer, and PPC linkages.

Cylinder-leakage testing helps distinguish internal cylinder leakage from control-valve faults when hydraulic drift is excessive. The described test applies to the blade tilt cylinder and optional ripper lift cylinder; the blade lift cylinder’s built-in piston valve prevents that measurement.

E-mode covers starting, lighting, preheating, wiper/washer, air-conditioning, and engine-stop faults. H-mode addresses braking, weak or delayed steering, no-travel conditions, high power-train oil temperature, low drawbar pull, pump noise, slow work equipment, and blade drift.

M-mode covers monitor displays, caution lamps, warning buzzers, gauges, the service meter, and panel lighting. Connector pin-number tables and system-specific flow diagrams support circuit tracing.

Overhaul Details, Tools, and Service Drawings

Component chapters include power-train pump work, final-drive assembly, recoil-spring tooling, lubricated-track inspection, and one-link field repair. Maintenance standards provide wear limits, clearances, adjustment data, torque specifications, and fluid and lubricant requirements.

Special-tool references include clutch-piston oil-leak tester 799-301-1600, floating-seal installer 791-545-1510, recoil-spring compressor 791-685-8006, and minimum swash-plate-angle gauge assembly 791-463-1200. Dimensioned tool sketches support local manufacture of the designated workshop fixtures.

Hydraulic/HSS pump assembly includes swash-plate positioning and test-bench checks. The later pump maintenance-standard page reserves adjustment for qualified distributors.

Visual references include the power-train hydraulic circuit, steering/work-equipment hydraulic circuits, cab and canopy electrical circuits, connector location and pin-arrangement views, Torqflow sectional and exploded views, and hydraulic/HSS pump and motor sections.

Contaminated or tilted floating seals in final drives and rollers, or damaged track-bushing seal surfaces, can cause oil loss. Miscentered link-press tooling can damage link bores, pins, and bushings; incorrect support and positioning during hydraulic/HSS pump piston assembly can damage the rocker cam and cradle.

Because this manual covers stored-energy recoil springs, pressurized hydraulic circuits, and suspended power-train and undercarriage assemblies, repair work should be performed only with the machine secured, residual pressure released, and correctly rated lifting and press equipment.

Selected PPC Clearance and Blade-Lift Test Data

The steering PPC adjustment section specifies 0.3–0.5 mm between the disc and opposing piston when the disc contacts the piston on the other side. Its caution explains the risk of unintended movement if clearance is eliminated.

For both models across the listed serial groups, the blade-lift table gives a standard raising time of 2.5 ± 0.2 seconds and a permissible value of 3.0 seconds, with hydraulic oil at 45–55°C, full throttle, and an unloaded blade moving from ground level to maximum height.