RING WEAR 8C3836 - Caterpillar

Illustration 1 g02327875
Pilot Manifold (1) Oscillating axle lock solenoid valve (2) Swing brake release solenoid valve (3) Heavy lift solenoid valve (4) Hydraulic lockout solenoid valve (5) Transmission shift solenoid valve
Illustration 2 g02328134
The cross section is identical for all of the solenoid valves. (6) Button for manual operation (A) Pilot pressure - Inlet port (B) Port (C) Port to tankThe pilot manifold includes solenoid operated pilot control valves. The following solenoid valves are cartridge type solenoid valves: oscillating axle lock (1), swing brake release (2), heavy lift (3), hydraulic lockout (4) and transmission shift (5) .Each solenoid valve includes a cartridge with a spool and a spring. A mechanical pin can be depressed in the head of the solenoid which permits manual operation of the valve.When the solenoid is de-energized, pilot pump oil pressure enters pilot pressure port (A) of the valve block. The oil flow from port (A) through the passage is stopped by the regulating spool.A connection is made between the pilot line (B) and the control device through tank port (C). Tank port (C) goes to the tank return line so that the pilot line is without pressure.When the solenoid is energized, the connection between port (A) and port (C) is closed. Port (B) is connected to port (A) and pilot oil pressure can go to the respective control device.To relieve pressure in the spring chamber passage, the spool is connected to the tank return line when the solenoid is de-energized.