Durango 4WD V8-4.7L Flex Fuel (2008)
Thermostat: Description and Operation
Description
DESCRIPTION
CAUTION: Do not operate an engine without a thermostat, except for servicing or testing.
The thermostat on the 5.7L gas powered engine is located beneath the thermostat housing (1) at the front of the intake manifold.
On the 3.7L/4.7L engine the thermostat (4) is designed to block the flow of the coolant bypass journal by 50% instead of completely blocking the flow.
The thermostat is a wax pellet driven, reverse poppet choke type.
Coolant leakage into the pellet container will cause the thermostat to fail in the open position. Thermostats very rarely stick. Do not attempt to free a
thermostat with a prying device.
The same thermostat is used for winter and summer seasons. An engine should not be operated without a thermostat, except for servicing or testing.
Operating without a thermostat causes longer engine warm up time, unreliable warm up performance, increased exhaust emissions and crankcase
condensation that can result in sludge formation.
