Illustration 1 | g00814174 |
(1) Diverter valve for the left front brake
(2) Oil cooler for the left front brake (3) Screen (4) Diverter valve for the right front brake (5) Oil cooler for the right front brake |
Torque converter and front brake cooling oil coolers (2) and (5) are located behind the engine above the torque converter. Engine coolant from the water pump flows through the torque converter and front brake cooling oil coolers. Then, the engine coolant flows back to the cylinder block.
The front brakes are cooled by oil. The cooling oil for the right front brake comes from diverter valve (4). Diverter valve (4) gets oil through lines from the screen mounted to the left side of the frame. Oil to the screen comes from the torque converter outlet relief valve. Some of the oil from the torque converter outlet relief valve goes for lubrication of the oil pump drive. The cooling oil for the left front brake comes from diverter valve (1). Diverter valve (1) receives oil through lines from the last section of the torque converter pump (front brake cooling). Oil also comes through lines from the parking brake valve bypass. The oil for diverter valve (1) passes through screen (3) before entering oil cooler (5).
When the service brakes are applied or when the retarder is used, diverter valves (1) and (4) will send the oil through oil coolers (2) and (5) to the front brakes. When the front brakes are not used the oil is sent straight to the front brakes. The oil is not sent through the oil coolers.
Balance lines maintain an equal pressure between the oil coolers. Lines come from the outlet side of the screen (3). These lines supply oil to the torque converter outlet relief valve.
Illustration 2 | g00815056 |
Rear brake oil coolers (6) are located on the right side of the engine. Engine coolant from the water pump flows through rear brake oil coolers. Then, the engine coolant flows back to the cylinder block.
The rear brakes are cooled by oil. The cooling oil comes from the brake cooling section of the torque converter, parking brake release, and brake cooling gear pump, the two-section hoist hydraulic pump, and the single section of the hoist hydraulic pump. Screens are located at the inlets to the rear brake oil coolers (6).
The oil flow from the rear section of the hoist and rear brake cooling gear pump will flow to the hoist control valve. When the hoist control valve is in either the HOLD or the FLOAT position, oil will flow through the hoist control valve to the rear brake oil coolers. After the oil goes through the rear brake oil coolers, the oil will flow to the rear brakes. After the oil flows to the rear brakes, the oil will return to the torque converter, hoist, and brake section of the hydraulic tank.
The oil flow from the front section of the hoist and rear brake cooling gear pump will flow to the hoist diverter valve. When the oil is not needed for the hoist circuit the oil flows through the hoist diverter valve to the rear brake oil coolers. After the oil goes through the rear brake oil coolers, the oil will flow to the rear brakes. After the oil flows to the rear brakes, the oil will return to the torque converter, hoist, and brake section of the hydraulic tank.
Oil from the rear brake cooling section of the torque converter, parking brake release, and brake cooling gear pump also flows to the rear brake oil coolers. After the oil goes through the rear brake oil coolers, the oil will flow to the rear brakes. After the oil flows to the rear brakes, the oil will return to the torque converter, hoist, and brake section of the hydraulic tank.
The rear brake cooling circuit has a rear brake oil cooler relief valve in the torque converter, hoist, and brake section of the hydraulic tank. The rear brake oil cooler relief valve prevents excessive pressure. The rear brake oil cooler relief valve opens at