How to Change a Thermostat on a 240SX

The 240SX is an automobile made by the Nissan Motor Company between 1988 and 1998. The radiator is located at the rear top of the radiator and is connected by a hose to the rest of the coolant system. It monitors the temperature of the engine and regulates the flow of coolant to keep the engine at a consistent temperature. Changing the thermostat at the first sign of overheating will prolong the life of the engine. Thermostats are available at most auto parts stores and contain replacement gaskets for the secure installation.

Instructions

1

Place the vehicle into park and open the hood. Locate the thermostat by following the main radiator hose from the radiator to the engine. In a 240SX, the radiator is located just behind the latch on the back side of the radiator.

2

Unscrew the bolt that holds the thermostat housing to the main radiator with a socket wrench. Pry the edge of the housing cover off using a flat head screwdriver and set the cover aside.

3

Slide the edge of a putty knife under the gasket left after removing the housing cover. Scrape at it lightly to get it all off, and then buff the area with a piece of steel wool to remove any remaining gasket debris.

4

Reach inside the housing and pull the thermostat out of its socket. Remember the orientation of the thermostat in the housing to ensure accurate replacement with the new.

5

Insert the new thermostat into the housing and verify it is secure. If installed correctly, it will not shift or pop out of the housing. Keep trying to get it in place until it is fully seated.

6

Position a replacement gasket over the housing opening and align the two holes over the drilled mounting holes in the housing.

7

Fit the housing cover over the gasket and align the cover holes over the gasket and housing holes. Insert the bolts and tighten them down securely with the socket wrench. Tighten it enough that it compresses the gasket and the bolts dont turn easily.

8

Check the radiator fluid level by unscrewing the radiator cap and visually inspecting it. Fill it with new fluid until the level is visible at the full mark. Leave the cap off the radiator.

9

Start the engine on the 240SX and let the motor idle for approximately 5 minutes. This process helps cycle fluid through the radiator system and removes air. Add fluid to raise the level again and then reconnect the cap securely.