Excavator Pump Parts Hydraulic Pump Repair Parts PSVD2-26E/27E Set Plate for KYB Kayaba Excavator Control the movement of all piston shoes and prevent them from pulling away from the swash plate. As the cylinder block rotates rapidly under heavy high‑pressure loads, springs push the cylinder block to press piston shoes onto the swash plate inclined plane. The set plate wraps around piston shoe tails to restrain outward flight, ensuring persistent contact between piston shoes