Excavator Pump Replacement Parts A10V71 SET PLATE R902437512 Excavator Spare Parts Core Functions Enable piston return for oil suction. The swash plate drives pistons inward to build oil pressure. As components rotate to the suction side, pressure drops. The Set Plate retains all Piston Shoes and pulls pistons out of the cylinder block, expanding cylinder bore volume to draw in oil. Locate and restrain every piston shoe. Each piston shoe neck runs through holes in the set