The Dodge 318 was manufactured for several decades and underwent many changes. One thing that stayed basically the same was the thermostat. The thermostat performs two functions. It keeps roughly half of the coolant in the engine on initial start-up and while the car warms up. After the car warms up, the thermostat regulates the flow of the coolant to keep the engine at the best operating temperature. Once the thermostat goes bad, you have to replace it, which you can do at home using a few basic tools.
Open the hood and locate the thermostat housing. The thermostat housing is on top of the radiator at the very front of the engine. It is the metal tube connected to the upper radiator hose.
Loosen the hose clamp that holds the upper radiator hose to the thermostat housing.
Pull the upper radiator hose from the thermostat housing with your hands.
Loosen and remove the nuts that hold the thermostat housing to the engine. Use a combination wrench to loosen the nuts.
Pull the thermostat housing from the engine with your hands.
Remove the thermostat by pulling it from the engine with your hands.
Scrape the old gasket off the thermostat housing and the engine using the razor-blade scraper.
Put the new thermostat in the location where the old one was.
Put a new gasket over the studs for the thermostat housing.
Place the thermostat housing back on the engine. Tighten the nuts with a combination wrench.
Push the upper radiator hose onto the thermostat housing. Tighten the hose clamp with a screwdriver.
Start the vehicle and allow it to reach operating temperature. Verify that the vehicle is not overheating.
