GLASS-REAR 3846959 - Caterpillar

Fan Motor
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Rear of the Machine (4) Fan motor.The fan motor (4) is a hydraulic gear motor that is located at the rear of the machine in front of the engine radiator. The machines that are high ambient will be equipped with a piston motor. The fan motor turns the fan which is mounted on the motor shaft. The fan pulls air through openings in the side and openings in the top of the machine behind the engine compartment. After the air is pulled through the openings, the air passes through the following components: Air To Air After Cooler, hydraulic oil cooler, the radiator and the air conditioner condenser. Finally, the air exits the rear of the machine.Thermostatic Valve
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Left Side of Engine Compartment (12) Thermostatic Valve.Thermostatic valve (12) controls the flow of the fan pump that is based on the temperature of the engine coolant. The engine coolant passes across the probe end of the thermostatic valve as the coolant flows from the radiator outlet to the coolant pump.When the engine coolant is below 70 °C (158 °F), the thermostatic valve allows oil from the flow control spool in the pump pressure compensator valve to flow to the tank. This causes the pump to destroke. The pump will also produce less oil flow. The speed of the engine cooling fan will decrease.When the engine coolant is above 90 °C (194 °F), the thermostatic valve blocks oil flow from the flow control spool in the pump pressure compensator valve to the tank. This causes the pump to upstroke. When the pump upstrokes, pump flow to the fan motor is increased. The fan motor speed increases and the fan motor circulates more cooling air.The thermostatic valve varies the amount of oil flow that passes through the thermostatic valve as the temperature of the coolant changes from 70 °C (158 °F) to 90 °C (194 °F). During this temperature change, the thermostatic valve is not totally open or totally closed.Case Drain Filter
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Pump Compartment (11) Case drain filter.The case drain filter (11) for the fan pump is located above the pump drive.Low Pressure Standby
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Hydraulic Fan System (1) Bypass valve. (2) Oil cooler. (3) Fan. (4) Fan motor. (5) Check valve. (6) Flow control spool. (7) Pressure cutoff spool. (8) Fan pump. (9) Destroke actuator. (10) Bypass valve for the case drain filter. (11) Thermostatic valve.When the engine is started and the engine coolant is cold, the bias spring causes the fan pump (8) to upstroke. When the pump upstrokes, the pump will produce flow. The fan pump is on STANDBY. At STANDBY, the pump produces low flow at approximate pressure of 2000 kPa (290 psi). Thermostatic valve (12) allows oil from the right side of the flow control spool (6) to flow to tank. The pump system pressure will start to increase. The pump system pressure works against the spring force of the flow control spool and the spring force of the pressure cutoff spool (7). When the system