There are no
repairs or adjustments to be made on the thermostat. The unit must be replaced when it
fails to operate properly. A stuck thermostat can either cause engine overheating or
thermostat is stuck closed, coolant will not circulate through the radiator. As a result,
overheating could make the coolant boil.
thermostat is stuck open, too much coolant may circulate through the radiator and the
engine may not reach proper operating temperature. The engine may run poorly for extended
periods in cold weather. Engine efficiency (power, fuel mileage, and driveability) will be
for thermostat replacement is as follows:
remove the thermostat, drain the coolant and remove the upper radiator hose from the
the retaining cap screws holding the thermostat housing to the engine. Tap the housing
free with a rubber hammer. Lift off the housing and thermostat.
all of the old gasket material off the thermostat housing and sealing surface of the
sure that the housing is not warped. Place it on a flat surface and check the gaps between
the housing and the surface. If warped, file the surface flat. This action will prevent
sure the temperature rating is correct. Then place the thermostat into the engine.
Normally, the pointed end on the thermostat should face the radiator hose. The pellet
chamber should face the inside of the engine.
the new gasket with approved sealer. Start the cap screws by hand. Then torque them to the
manufacturer's specifications in an alternating pattern do not overtighten the
housing bolts or warpage and or breakage may result. Most housings are made of soft
aluminum or "pot metal."