How do I Replace the Thermostat in a 1995 4Runner?

The thermostat on your Toyota 4Runner controls the flow of coolant between the radiator and engine. As the engine begins to heat up the thermostat opens--like a door--to allow coolant from the radiator to cool your engine. Often when the thermostat becomes defective, it will remain stuck open. This leads to over-cooling of the engine. A common sign of this problem is cold air instead of warm when you operate the trucks heater. You can remove the old thermostat on your 1995 4Runner right at home. The repair should take you 35 minutes to do.

Instructions

1

Raise the hood on your 4Runner. Remove the radiator cap and set it to the side of your work area.

2

Place a coolant drain pan beneath the radiator on the passengers side. Slide head first under the truck and locate the drain petcock on the bottom corner of the radiator. The truck sits high enough off the ground, so you dont have to jack it up.

3

Turn the drain petcock by hand counterclockwise until coolant starts to flow from it. Allow the coolant to drain for approximately 90 seconds then close the drain petcock.

4

Working from the top side of the truck, follow the top radiator hose over to its connection on the thermostat housing. Use a pair of pliers to squeeze the two metal tabs together on the spring tension clamp that hold the hose in place. Drag the clamp back on the hose 8 inches and release it.

5

Pull the top radiator hose away from the thermostat housing. Lift the hose up vertically to allow any coolant in the hose to back-fill into the radiator.

6

Remove the two mounting bolts that secure the thermostat housing to the engine with your socket wrench. Some engine models will have three mounting bolts. Place the bolts to the side of your work area.

7

Lift the thermostat housing from its position to reveal the thermostat. Note the position of the thermostat--spring down. Remove the thermostat by simply lifting it out of position and immediately install your new thermostat.

8

Flip the thermostat housing cover over. Remove the rubber gasket around the inner lip of the housing. Install your new gasket just as you removed the old one. Place the thermostat housing back into position over the thermostat. Thread each of its bolts by hand and tighten them until snug. Set your 3/8-inch drive torque wrench to 14 foot-lbs. and secure the housings bolts in place.

9

Push the top radiator hose back onto its connection on the thermostat housing. Squeeze the tabs together on the spring tension clamp with your pliers and move the clamp back down the hose into its original mounting position.

10

Insert a funnel into the fill hole on the radiator. Carefully pour the coolant from the drain pan through the funnel, back into the radiator. Put the radiator cap back on securely and shut your 4Runners hood.