LINES GP-GREASE 3904831 - Caterpillar

Illustration 1 g00753632
Piston pump (1) Case drain port (2) Inlet port (3) Outlet portThe piston pump is a pressure compensated variable displacement piston pump. The piston pump charges the service brake system and the parking brake system. The piston pump maintains the pressure in the service brake system and the parking brake system. The piston pump destrokes after the correct system pressure is achieved. The piston pump also supplies oil to the suspension system and pilot oil to the hoist control valve.The piston pump is located on the left side of the engine.
Illustration 2 g00753629
Location of piston pumpA connection from the top of the hydraulic tank supplies oil to inlet port (2). Outlet port (3), which is directly opposite the inlet port, delivers oil to the braking system.Oil drains to the hydraulic tank through case drain port (1). The case drain oil passes through a manifold and a screen then enters the hydraulic tank.When there is demand for flow in a brake system the system pressure is reduced. The piston pump senses the reduction in system pressure and upstrokes. The piston pump recharges the brake system.