Komatsu PC800-8 PC850-8 Main Control Valve
Part Numbers: 709-14-95500, 709-14-94200
Common Faults
- Insufficient flow of main control valve, weak machine performance and slow operation speed
- Spool sticking, single function failure and uncoordinated combined movements
- Internal leakage of valve block, insufficient pressure under load and speed drop during operation
- External oil leakage on valve body, aged and damaged seals and O-rings
- Wear of valve bore and spool, fluctuating system pressure and jerky operation
- Relief valve malfunction, system pressure fails to build up or rises abnormally high
Purchasing Recommendations
- Verify part numbers and machine serial number to confirm compatibility with Komatsu PC850 hydraulic excavator
- Prioritize OEM parts or high-quality remanufactured parts; be cautious of low-cost generic spare parts
- Inspect valve body for cracks, check integrity of port threads and mounting flange before acceptance
- Confirm the main control valve assembly comes with a complete seal kit for easy installation and replacement
- Request warranty from supplier and retain factory inspection report
- Clean hydraulic tank, replace hydraulic oil and flush pipeline contaminants during valve replacement to prevent secondary wear