Komatsu PC300-6, PC300LC-6, PC350-6, and PC350LC-6 1995–2002 Service & Repair Manual (P/N SEBM014307)

• Covers 1995–2002 Komatsu PC300-6, PC300LC-6, PC350-6, and PC350LC-6 hydraulic excavators, including HD and LL variants
• Original OEM publication P/N SEBM014307 (May 2002)
• Contains 809 pages of structural overviews, component logic, and system diagrams for descriptive repair reference
• Details the SAA6D108-2 engine assembly and hydraulic system configuration
• Documents serial numbers 33001 and up (PC300-6/LC-6) and 12001 and up (PC350-6/LC-6)
• Maps out the complete architecture for the CLSS (Closed-center Load Sensing System)
• Explains disassembly and assembly procedures, testing and adjusting metrics, maintenance standard limits, and troubleshooting for the machine monitor system and electronic control system
• Features wiring diagrams (including actual electric wiring diagrams), electric circuit diagrams, hydraulic circuit diagrams, hydraulic piping drawings, and specification drawings

Component and System Documentation

The 1995–2002 Komatsu PC300-6 and PC350-6 service manual delivers in-depth technical breakdowns of the machine's primary assemblies. It maps out the core operating principles behind the engine power train, swing circle, track frame, and control valves. You get a clear view of the pump controllers, solenoid valves, and the complex stage-logic of the 6-spool and 10-spool control setups. Having these structural insights accelerates diagnostic testing and helps technicians understand system interactions before turning a single wrench. Always review the included heavy machinery safety protocols and pressure-release procedures prior to inspecting hydraulic components. This 2002 final edition serves as an essential descriptive baseline for planning a safe, efficient repair.

Advanced Shop Operations

By utilizing this PDF, mechanics can follow factory procedures for tasks that typically require a costly dealership visit, such as adjusting valve clearances, setting fuel injection timing, measuring blow-by pressure, and bleeding air from the hydraulic cylinders. Executing these routines with exact OEM metrics prevents trial-and-error component swapping and drastically minimizes bay time. When working on these Dash-6 excavators, technicians often misdiagnose sluggish CLSS hydraulic responsiveness as a failing main pump. In reality, the root cause frequently lies in an uncalibrated LS valve differential pressure or a malfunctioning LS-EPC valve. Additionally, failing to thoroughly bleed air from the swing motor, travel motor, and center swivel joint cases after reassembly will cause immediate internal cavitation and severe mechanical damage. Applying the correct workflows ensures a reliable fix.

Specification and Reference Highlights

Technical data is organized into extensive tables that cover standard tightening torques for metric bolts, flared nuts, split flange bolts, and O-ring boss joints. The documentation details crucial hydraulic performance metrics. For example, it lists a relief cracking pressure of 16.7 ± 6.9 kPa for the hydraulic tank filter. Main hydraulic system pump pressure ratings sit at 34.8 MPa. On the powertrain side, the SAA6D108-2 engine flywheel horsepower pushes 172.8 kW (231.7 HP) at 2,050 rpm. Essential fluid capacities are also clearly defined, noting a 262 L fuel tank requirement to support standard shop maintenance schedules.