The thermostat in the 1995 Buick Skylark 2.3-liter engine rests inside the engine intake located on the top of the engine. The thermostat regulates engine temperature by restricting the flow of coolant through the engine. When the thermostat fails, it fails in the open position, meaning that coolant flows unrestricted through the engine and the engine cannot heat up to proper levels. When this happens, you must replace the thermostat.
Tools Used: Tools, Drain pan, Pliers, Socket set, Wire brush, Funnel
Change a Thermostat
Drain approximately 2 gallons of radiator fluid from the petcock located on the bottom of the radiator into a clean drain pan. Use a pair of pliers to open the petcock if you cannot open it by hand. Follow the upper radiator hose to the thermostat housing located on the engine. Remove the hose clamp with a pair of pliers and pull the hose off the engine. Remove the bolts that secure the housing to the engine with a socket and ratchet. Use the ratchet extension bar supplied with your socket set to avoid hitting any accessories located around the thermostat housing. Remove the thermostat housing and housing gasket off the engine. Pull the old thermostat out of the engine.
Clean the surface of the engine and the bottom of the thermostat housing with a clean towel. Use a wire brush if you cannot get the old gasket material off the surfaces. Place the new thermostat into the engine with the large spring submerged into the engine. Place the gasket over the thermostat and then bolt the thermostat housing back onto the engine. Place the hose back onto the thermostat and secure it with a hose clamp. Pour the 2 gallons of fluid into the radiator filler cap located on the top of the radiator.