The 4.2-liter engine in the 2001 Ford F-150 pickup truck has its thermostat located on the front of the cylinder head on the engine. The thermostat is critical to the engine because it regulates the temperature of the coolant coming into the engine from the radiator. If the coolant is too hot, the truck will overheat and damage the engine or cylinder head. A new thermostat for your F-150 is available at most auto parts stores or the Ford dealer, and you can change it yourself.
Instructions
- 1
Open the hood of your F-150 and locate the radiator cap. Make sure the engine is cool, then open the cap and set it aside.
2Place a clean drain pan or bucket under the drain petcock on the bottom of the radiator. Open the petcock and drain the coolant down until the level falls below the level of the thermostat housing. Close the petcock to keep the remaining coolant in the radiator.
3Loosen the hose clamp on the engine end of the upper radiator hose with a flat screwdriver and remove the hose from the water inlet on the engine. Set the hose aside for now.
4Locate and remove the two mounting bolts on either side of the water neck, then remove the water neck from the engine, using a socket and ratchet. Pull the thermostat out of the hole under the neck. Clean any old gasket off the engine or the water neck with a gasket scraper.
5Install a new thermostat and gasket in the hole in the cylinder head in the engine, then position the water neck over it. Install the two mounting bolts into the water neck and tighten the bolts with a socket and ratchet. Torque the bolts to 80 inch-lbs. with a torque wrench.
6Install the upper radiator hose onto the water neck and tighten the hose clamp to secure it, using a flat screwdriver. Refill the radiator with coolant, then start the engine and let it run until it reaches normal operating temperature. Add coolant until the system is full and replace the radiator cap on the radiator.
