Excavator Komatsu PC850-8 Fan Pump Auxiliary Pump Assembly 708-1W-00910 708-1W-00901 708-1W-00900 Common Faults Insufficient output flow of fan pump, low fan speed and engine overheating Low pressure of auxiliary pump, slow response of pilot control Abnormal noise during pump operation with housing vibration Oil leakage at pump mating surface and shaft end, damaged oil seals and gaskets Wear of internal gears and flow distribution components, pump overheating Severe pressure