2007 Komatsu PC400LC-8 Galeo Hydraulic Excavator Shop Manual (P/N CEBM018801)

• Covers the Komatsu PC400LC-8 Galeo, serial A88001 and up, equipped with the SAA6D125E-5 engine.
• Details hydraulic pressure testing, PC/LS control checks and adjustment, EPC/PPC output checks, hydraulic drift diagnosis, and travel/swing motor leakage measurement.
• Explains final-drive and swing-machinery disassembly and assembly, including planetary gearing, bearings, and related maintenance standards.
• Documents idler and recoil-spring work, track-chain separation and assembly, sprocket replacement, and roller floating-seal assembly precautions.
• Includes boom, arm, and bucket cylinder disassembly and assembly, plus center swivel joint removal, installation, and resealing.
• Combines failure-code troubleshooting with E-mode electrical and H-mode hydraulic/mechanical symptom charts, connector-specific checks, and normal test values.
• Provides whole-machine Hydraulic Diagram and Electrical Circuit Diagram foldouts for tracing hydraulic connections and wiring.

This 928-page PDF contains Komatsu Shop Manual CEBM018801, dated December 2007. Written for service technicians performing workshop repairs, it combines component operation with inspection standards, testing, adjustment, and repair procedures rather than routine operator maintenance alone.

Hydraulic Control and Pump Diagnosis

The hydraulic sections explain the Closed Center Load Sensing System (CLSS) and the variable-displacement pump identified as HPV160+160 (190) in the specifications and pump chapter. LS valves, PC valves, and EPC solenoids are covered in relation to load sensing, pump torque control, and engine-speed feedback. Emergency pump drive switch operation is explained separately.

The Hydraulic Piping Drawing and CLSS system diagram support the functional descriptions of pressure compensation, regeneration, and merge-divider operation. Drift testing distinguishes cylinder leakage from control-valve or PPC-valve causes. Tool tables identify the LS differential-pressure gauge, 799-401-2701, alongside hydraulic testers and connection adapters.

Pump repair coverage includes removal and installation and input-shaft oil-seal replacement, not a complete internal pump overhaul. Control-valve coverage includes removal, pressure-compensating valve seal work, and assembly precautions; the PPC sections also specify assembly precautions. Hydraulic air-bleeding procedures and PM Clinic Service inspection sheets support post-repair checks.

Electrical Troubleshooting and Attachment Setup

The machine monitor's service mode covers live readings, failure histories, pump absorption-torque adjustment, and attachment settings. Electrical fault tables connect a detected condition with controller response, machine symptoms, possible causes, and pin-level checks. Engine electronic fault diagnosis is included alongside machine-controller troubleshooting.

The Machine Control System Diagram and engine-start/battery-charging circuit diagram show how the control and power-supply circuits connect. HD30 and DT connector repair information covers terminal handling and crimping, while T-adapter tables identify the connections used for electrical measurements. KOMTRAX TH300 and TH200 terminal checks are covered where fitted.

For attachment-equipped machines, the manual distinguishes breaker operation from other attachment settings and addresses flow distribution during combined operation. It warns that using B mode with a non-breaker attachment can damage hydraulic components. A separate electrical repair caution identifies another specific risk: reversing supply and ground at a pump pressure sensor can destroy the sensor.

Power Train, Cooling System, and Component Replacement

Beyond the internal assembly work listed above, removal and installation chapters address the engine-and-pump assembly, swing circle, revolving frame, and counterweight. Cooling-system work covers the radiator, hydraulic oil cooler, and aftercooler. Work-equipment installation includes pin-clearance adjustment, while cab coverage extends to glass replacement and front-window adjustment.

Detailed engine work requires the separate Engine Shop Manual. This machine manual refers cylinder-head, injector, fuel-supply-pump, and engine front/rear seal procedures to that publication. It also directs technicians there for compression testing, valve-clearance adjustment, other engine-specific tests, and S-mode engine troubleshooting. Machine-level engine removal and electronic fault diagnosis remain part of this volume.

Specification Highlights and Reference Data

Reference sections provide torque tables for bolts, hose nuts, and split-flange connections, together with fluid-capacity and lubricant charts. Maintenance standards cover the track frame, carrier rollers, track rollers, and sprocket assemblies, with standard dimensions, fits, clearances, and applicable repair limits. Component-weight tables include the boom and counterweight; standard-value tables distinguish new-machine benchmarks from permissible service values.

Working on this excavator requires adherence to factory safety precautions for stored hydraulic pressure, supported work equipment, recoil springs, and heavy-component lifting.