PUMP GP-TANDEM 1G7577 - Caterpillar

Illustration 1 g02594456
(1) Piston motor (hydraulic fan)The fan is driven by a piston motor. Oil enters piston motor (1) and that oil causes the internal pistons to reciprocate in the barrel. This motion is converted into rotary motion. The rotary motion of the barrel turns the shaft. Fan speed depends on the amount of oil that is supplied to the motor (1) .The piston motor (1) has an internal makeup valve. The makeup valve allows the fan to stop gradually when the engine is shut down. When the fan is spinning and there is no supply oil, the makeup valve redirects the oil inside the motor. Oil will flow from the outlet side of the motor to the inlet side of the motor. The makeup valve prevents cavitation of the motor.The piston motor is equipped with a case drain. The case drain allows the internal motor leakage to drain from the motor case back to the hydraulic tank.