BODY-PRESSURE 5S4438 - Caterpillar

Illustration 1 g00618494
In the engine cooling system, the radiator cooling piston pump provides oil flow to the radiator cooling fan motor. The radiator cooling fan motor drives the radiator cooling fan.The radiator cooling piston pump is the center pump in a stack of three pumps. The stack of three pumps is mounted in the center of the pump drive. The radiator cooling piston pump provides oil flow to the motor for the engine cooling system. Radiator cooling piston pump regulator control valve is mounted on the top right rear corner of the pump.The solenoid valve for radiator cooling piston pump regulator control valve is mounted above the swing piston pump on the control manifold.The radiator cooling fan motor is mounted in front of the engine radiator at the front of the right hand module. The radiator cooling fan motor lines are connected to the makeup valve.The temperature sensor is located at the left front corner of the engine.Operation of the Engine Cooling System
The engine temperature sensor provides a signal about the temperature of the engine coolant to the Engine Control Module (ECM). The engine coolant temperature is monitored by the ECM. The ECM sends a Pulse Width Modulated (PWM) signal to the control solenoid valve. The control solenoid valve modulates the signal pressure from the control solenoid valve back to the radiator cooling piston pump control valve in order to control the pump flow.The Engine Control Module (ECM) is located on the right front corner of the engine.The flow from the radiator cooling piston pump is directed to the radiator cooling fan motor, the makeup valve, and the regulator control valve.The Engine Control Module (ECM) also sends a signal about the engine coolant temperature to the main module of the Vital Information Management System (VIMS) over the Cat data link. The VIMS main module makes the information about the temperature available to the operator in the cab. The VIMS main module is located behind the cover of the large electrical panel that is located in the cab support.Operation of the Radiator Cooling Fan
Illustration 2 g00503672
Engine Cooling System Fan Speed ChartWhen the engine coolant is operating below 88°C (190°F), the fan will operate at minimum speed of 375 20 rpm.When the engine coolant is operating above 98°C (208°F), the fan will operate at maximum speed of 970 20 rpm.Note: The fan speed may vary on machines that are equipped with the hydraulically driven generator.If an electrical failure of the system occurs, the fan will operate at maximum speed.The radiator cooling system has the following advantages:
Reduced fuel consumption in most conditions
Reduced overcooling of the engine at low ambient temperatures
Faster warming of the engine