HARNESS AS-CHASSIS 3107900 - Caterpillar

coolant system contains the following components:
Radiator
Pressure cap for the radiator
Fan for the radiator
Drive pulley (if equipped) for the fan
Water pump
Exhaust gas cooler (NRS)
Water temperature regulator
Housing for the water temperature regulator
Coolant temperature sensorThe coolant flows from the bottom of the radiator to the centrifugal water pump. The water pump is installed on the cylinder block above the timing case. The water pump is driven by a pulley. The crankshaft pulley turns a belt which drives the pulley of the water pump.The water pump forces the coolant to flow to the water temperature regulator. When the engine is cold, the water temperature regulator is closed. Then, the coolant flows directly into the cylinder head. When the engine warms, the water temperature regulator begins to open. Then, the regulator allows some of the coolant to flow to the top of the radiator.The regulator opens fully when the engine reaches the normal operating temperature. When the regulator is fully open, the flow to the radiator is the maximum. However, the regulator does not close the flow of coolant into the cylinder head.Some coolant from the water pump is diverted into a cavity in the cylinder block. The coolant then flows from the cylinder block to the exhaust gas cooler. The coolant then flows out of the exhaust gas cooler through a coolant pipe to the water pump.Coolant flows continuously through the cylinder head and the top of the cylinder block. This coolant flows into the back of the water pump from the cylinder block. This coolant then mixes with the coolant that is pumped from the radiator by the water pump.The water temperature regulator maintains the correct engine temperature by adjusting the direct flow of coolant to the top of the radiator. The coolant is cooled by the radiator. Heat is removed from the coolant by cooler air which passes over the radiator fins. The fan causes a high volume of air to flow between the radiator fins to provide sufficient cooling. The coolant flows from the radiator through the bottom hose to the coolant pump.The engine has a housing for the water temperature regulator. The housing is installed on the left side of the cylinder head.The water temperature regulator housing is mounted vertically.