COVER AS. 2517634 - Caterpillar

Illustration 1 g06155626
(1) Shaft
(2) Fan Motor
(3) Port "T1" (Case Drain)
(4) Port "A"
(5) Port "B"
(6) Port "T2" (Plugged Case Drain)Fan motor (2) is a variable displacement motor. Shaft (1) is connected to the fan that draws air through the radiator. When you look at the motor from the shaft end, shaft (1) rotates in the counterclockwise direction to produce normal fan rotation.The fan pump delivers pressurized oil to port "B" (5). The speed of the fan motor is directly proportional to the output flow from the fan pump. The oil exits the fan motor through port "A" (4) as the fan motor rotates. This oil is then delivered to the hydraulic oil cooler.The case drain line for the fan motor is connected at port "T1" (3). Port "T2" (6) is a passage to the case drain oil. This port is plugged.The standard fan motor contains an anticavitation valve (not shown). The anticavitation valve prevents cavitation when the engine is OFF and the fan blade continues to turn due to momentum. The anticavitation valve is also used for rapid engine decelerations. In this case, the anticavitation valve prevents the motor from acting as a pump.The fan direction is controlled by varying the swashplate on the fan motor. The solenoid on the motor gets a current command when a reversal is desired, which changes the swashplate angle to reverse the fan.