Excavator Hydraulic Pump 708-1S-01111 708-1S-00130 708-1S-00510 Komatsu PC30MR-1 PC27R-8 PC30UU-3 Main Piston Pump Pressure Pump The PC27R-8 is a Komatsu small excavator (PC27R-8 / PC30R-8 platform). The hydraulic main pump is a main variable displacement piston pump , with a matching pilot gear pump. Common main pump part numbers: 708-1S-01111 (PC30MR-1), etc.; for the PC27R-8, please confirm with the original old part number. Common Faults Weak movement / slow operation: