VALVE GP-CONTROL 2166167 - Caterpillar

Piston Pump Brake and Hydraulic Fan
Illustration 2 g06217935
Rear of the tractor
The pump for the hydraulic fan and brake system is a variable displacement axial piston pump. When the engine is operating, the pump will always produce flow. The flow is created to satisfy the following demands:
The demand of the brake system
The demand of the hydraulic fan systemWhen the demands are met and the pressure compensator setting is reached, the pump will continue to produce flow on a limited basisPump Control Valve
Illustration 3 g03684343
View of the rear of the tractor
The pump control valve is mounted on the piston pump (brake and hydraulic fan). The pump control valve uses load sensing to control the system pressure. The piston pump (hydraulic fan and brake) will only produce enough oil flow to satisfy the demand of the hydraulic fan and brake system.Manifold for the Brakes
Illustration 4 g06217941The control manifold directs the oil from the brake and the hydraulic fan pump to the brake circuit and to the fan circuit.Brake Accumulator
Illustration 5 g03684393
Rear top access panel is removed
The brake accumulators maintain brake system pressure when the pump (hydraulic fan and brake) is not supplying oil. There are three brake accumulators in the brake system. The two accumulators shown above are used to maintain pressure for the front brake system.Service Brake Control
Illustration 6 g03185297
Cab removed
The service brake control valve for the service brakes provides the proper flow to engage the service brakes. The service brake control for the service brakes also balances the oil pressure between the front and rear brakes.Wheel Group
Service Brakes Cooling (Front Brakes Only)
Illustration 7 g03684423
Belly guards removed looking up at the right side of the engine
The transmission oil is cooled through the heat exchanger.
Illustration 8 g06217949
View of the rear of the tractor
Brake cooling oil is circulated through the brakes by the transmission scavenge Pump. The circulation of oil through the transmission oil cooler cools the tractor service brake. This tractor is equipped with cooling oil circulation for the service brakes, on the tractor unit. The transmission scavenge pump is an internal pump and is on the rear of the tractor. The scavenge pump sends some flow for the brakes through an orificed line and the rest of the flow goes to the sump. A check valve that opens up to sump, is used to maintain the pressure required to send some oil through the brakes.Service Brakes (Front)
Illustration 9 g03684446
Top View of front service brakes
There is a service brake located in each wheel group. The service brakes are applied by oil pressure from the service brake control valve. The service brakes are released by retraction springs. The service brakes are activated when the brake pedal is depressed.Parking brakes
The parking brakes are located in each of the wheel groups of the tractor. The parking brakes are applied by springs. The parking brakes are released by oil pressure from the parking brake solenoid.Parking Brake Control Valve
Illustration 10 g06217962The parking brake control valve controls the operation of the parking brake. The parking brake is applied when the parking brake solenoid is the de-energized