EJECTOR A 8A8248 - Caterpillar

Pilot Oil Circuit
Illustration 1 g01033316
(1) Pilot pumpPilot pump (1) supplies oil to the pilot manifold (8). The drive pump and the idler pump provides flow for the implements and travel circuits. Flow from the pilot system is used to operate different functions on the M325C Series machine. The major functions of the pilot system are listed below:
Activate all hydraulic control valves.
Release the swing parking brake.
Activate the cylinders for the oscillating axle.
Control engagement of the transmission clutches.
Change gears.
Operate the creeper speed.
Generate power shift pressure for the main hydraulic pump.
Illustration 2 g01033318
Pilot manifold (2) Oscillating axle solenoid valve (3) Swing brake solenoid valve (4) Solenoid valve for travel lockout (5) Implement activation solenoid valve (6) Transmission solenoid valve (7) Parking brake relief valve (8) Pilot manifold (9) Pilot relief valve
Illustration 3 g01033332
(10) Creeper speed solenoid valve (11) Pilot accumulator
Illustration 4 g01033340
(2) Oscillating axle solenoid valve (3) Swing brake solenoid valve (4) Solenoid valve for travel lockout (5) Implement activation solenoid valve (6) Transmission solenoid valve (7) Pressure reducing valve (8) Pilot manifold (9) Pilot relief valve (10) Creeper speed solenoid valve (11) Pilot accumulatorThe pilot control system for the M325C series machines is similar to the M300C series machines. Flow for the pilot system comes from pilot pump (1). The pilot circuit has a separate filter, accumulator (12), and relief valve (9) in order to regulate the maximum pilot pressure in the circuit.Pilot manifold (8) is located on the left side of the hydraulic cab riser, which is behind the cab. The manifold is bolted to the frame for the hydraulic cab riser. Pilot relief valve (9) limits the maximum pilot system pressure.Transmission solenoid valve (10) and pressure reducing valve (7) are part of the pilot manifold on the M325C Series machines.Illustration 4 shows