Komatsu WA470-3, WA470 Avance Wheel Loader Factory Shop Manual (P/N SEBM006307)

• Two Komatsu shop manual PDFs, 1,883 pages total: SEBM006307 covers the WA470-3 Avance loader, serial 50001 and up (897 pages, August 2001); VEBM480104 covers the WA470-3 wheel loader, serial WA470H20051 and up (986 pages, March 2000).
• Separates the major engine and power-train builds before repair work begins: S6D125 with the TCA38-8A torque converter for the 50001-up family; S6D125-1, Cummins MTA11 (STC), and SA6D125E-2 engine groups with the TCA38-4Z converter in the WA470H series.
• Covers major power-train repair procedures: torque converter and transmission removal, clutch-pack disassembly and reassembly, transmission control valve and ECMV service, drive shafts, front and rear axles, standard and limited-slip differentials, final drives, and center-hinge pin work.
• Provides hydraulic, steering, and brake procedures: pump and main control valve testing, PPC circuit diagnosis, emergency steering, brake pressure and accumulator checks, brake bleeding, wet-disc inspection, parking-brake release, and hydraulic-cylinder repair.
• Documents work-equipment and electronic controls: bucket positioner, boom kick-out, auto-leveler, work-equipment controller, auto-shift, ECSS, main and maintenance monitors, kick-down, transmission cut-off, and engine start/stop/preheat circuits.
• Supplies the supporting shop references: full electrical circuit sheets in the 50001-up volume, hydraulic schematics, controller diagrams, connector and pin-location views, fault-code charts, standard-value tables, torque data, fluid specifications, wear limits, and Komatsu special-tool part numbers.

Coverage by Publication and Serial Break

The 50001-up publication divides the machine into 50001-52999, 53001-53999, and 54001-up build groups rather than treating every loader as identical. It identifies the S6D125/TCA38-8A power train, separates serial-specific auto-shift and ECMV configurations, and shows the change from a center-bolt transmission filter to a spin-on filter at 54001. From that same break, the control documentation moves to a combined transmission and travel-damper controller with ECSS functions; the proportional-solenoid design changes again at 54101. The capacity tables also distinguish the hydraulic-system change from 294 liters on 50001-52999 machines to 280 liters from 53001 onward.

The WA470H publication is equally build-sensitive. It covers S6D125-1 through H20668, Cummins MTA11 (STC) from H20669 through H20941, and SA6D125E-2 from H20942 onward. Later sections separate emergency-steering, monitor, auto-transmission-pilot, brake, hydraulic-safety, and electrical revisions at further H-series breaks, including H21065, H21104, and H21164. This prevents selection of an engine test procedure, hydraulic layout, controller connection, or replacement component intended for a different build.

Repair, Testing, and Troubleshooting Depth

The power-train chapters trace oil flow and clutch application through the transmission hydraulic circuit, main relief and priority valves, selector valves, ECMV, accumulator and flow valves, and emergency manual spool. Factory procedures cover torque converter and transmission removal and installation, internal disassembly and reassembly, clutch-pack repair, control-valve overhaul, drive-shaft work, axle and differential removal, final-drive overhaul, center-hinge service, and inspection standards for disassembled parts.

Hydraulic and chassis coverage extends through the steering valve and orbit-roll unit, emergency steering, service- and parking-brake circuits, accumulators, slack adjusters, PPC valves, main control valve, hydraulic safety system, boom and bucket cylinders, work-equipment linkage, and bucket. Testing sections address stall performance, torque-converter and transmission pressure, steering pressure, brake performance and disc wear, brake bleeding, accumulator checks, hydraulic pressure and drift, bucket positioner and boom kick-out adjustment, monitor setup, and sensor checks. Cab, air-conditioning component, counterweight, fuel-tank, and work-equipment removal and installation are also covered; the WA470H volume adds tire procedures.

Electrical diagnosis goes well beyond a parts list. The PDFs include transmission, brake, and work-equipment hydraulic circuit diagrams; engine starting, stopping, and preheating circuits; kick-down and transmission cut-off schematics; auto-shift and ECSS controller diagrams; connector mounting locations; and pin-arrangement views. Troubleshooting is organized by system modes for engine performance, main and maintenance monitors, electrical faults, transmission control, hydraulic and mechanical chassis complaints, ECSS, and, in SEBM006307, the work-equipment controller. The WA470H PDF retains the serial-specific wiring legends and foldout insertion pages, but the separate large-format full-machine wiring foldouts referenced there are not embedded in that file.

Engine Scope, Special Tools, and Repair Cautions

These are chassis shop manuals. They include in-machine engine diagnosis and service such as speed, boost, blow-by, compression, and oil-pressure testing; variant-specific valve, injector, and fuel-injection adjustments; cylinder-head and auxiliary-component work; radiator service; and complete engine removal and installation. They do not replace the corresponding engine-series shop manuals required for full internal engine overhaul.

The tool lists identify intended Komatsu equipment, including multi-tachometer 799-203-9000, hydraulic tester 799-101-5002, clutch-pack lifting tools 793-615-1310 and 793-615-1320, center-hinge push-puller 790-101-2300, and hydraulic-cylinder repair stands 790-502-1003 / 790-502-2000.

Several assembly cautions are specific to these machines. The transmission PTO idler spacer and gear position are controlled items; an omitted spacer or misplaced gear can damage bearings and gear teeth. Parking-brake plates, discs, wave springs, and the marked end plate must return in the correct order or the wet brake can drag and overheat. Main-control-valve spools, springs, and shims are port-specific, while cylinder seals and backup rings must not be forced into place; either error can cause internal leakage or incorrect hydraulic response.

Repair work on raised equipment, pressurized hydraulic circuits and accumulators, wet brakes, driveline assemblies, and heavy axle or transmission components can cause severe injury or machine damage. Hands-on service should be performed by qualified technicians using the applicable Komatsu publication set, correct support and lifting equipment, and the specified test and repair tools.