Engine Coolant Thermostat: Description

WARNING: This page is about a different car, the 2006 Dodge Magnum, 2006 Dodge Charger, and 2006 Chrysler 300. However, it is still accessible from the selected car via links, so may be relevant.

The engine cooling thermostats are a wax pellet driven, reverse poppet choke type. The thermostats have an air bleed located in the thermostat flange. The air bleed allows internal trapped air during cooling system filling to be released. The thermostat on the 2.7L and 3.5L engines are located on the lower left side of engine, near the front. The thermostat on both engines are on the inlet side of the water pump.

The thermostat on the 5.7L/6.1L gas powered engine is located beneath the thermostat housing (1) at the front of the intake manifold.

Fig 1: THERMOSTAT

Courtesy of DAIMLERCHRYSLER CORP.

1 - VENT VALVE

2 - BYPASS VALVE

3 - THERMOSTAT HOUSING SEAL

4 - MAIN VALVE

The thermostat on the 3.0L Diesel engine is integrated into the thermostat housing located at the front of the right intake manifold and is serviced as an assembly. A rubber seal is used to seal the thermostat housing to the intake manifold. The thermostat contains the following components:

Main Valve (4) - Controls coolant flow through the radiator
Bypass Valve (2) - Controls coolant flow through the bypass passage to the inlet side of the water pump
Vent Valve (1) - Vents the cooling system via a ball valve when it is filled and when the engine is running
Thermostat Housing Seal (3)