How to Replace a Thermostat in a 1995 Ford Bronco XLT
- 1). Open the hood of the Bronco. Locate the heater hose in the middle of the engine, on the top. This is the large black rubber hose for the cooling system. Place a pair of radiator hose pliers, or needle-nose vice grips, onto the hose to close it off from the engine. Place a drain pan beneath the front of the engine, just to the rear of the radiator fan.
- 2). Remove the heater hose clamp from the heater hose, where it is attached to the thermostat housing on the engine. Use a ratchet and socket to loosen the hose clamp, or use pliers if it is a squeezable clamp. Slide the heater hose up and off of the thermostat housing by hand. Aim the heater hose open, end down, into the drain pan, so as not to spill residual coolant anywhere else.
- 3). Remove the thermostat housing from the engine, using a ratchet and socket. Remove the old thermostat from the thermostat housing, or the front of the engine, using pliers to handle the thermostat. Do not touch the old thermostat with your bare hands. Allow the coolant to fall from the engine into the drain pan for about 30 seconds.
- 4). Scrape the thermostat engine-mounting surface with a razor blade to remove previous sealer or debris. Be sure not to get debris into the exposed hole in the front of the engine. Scrape the surface of the engine from the middle outward. Scrape the mounting edge of the thermostat housing with the razor blade to ensure proper mounting.
- 5). Install thermostat gasket material onto the new thermostat. Install the new thermostat by hand onto the engine mounting surface. Install the thermostat housing over the new thermostat and gasket by hand. Install the housing mounting bolts to 28 foot-pounds (336 inch-pounds) using a torque wrench and socket. Do not over-tighten the thermostat housing, or you will damage the new gasket.
- 6). Install the heater hose back onto the thermostat housing. Slide the hose clamp over the hose and the new housing. Tighten the clamp with a ratchet and socket until it is snug. Use pliers to move the clamp, if the clamp is the squeezable type.
- 7). Remove the radiator cap from the Bronco. Add coolant to the radiator until the radiator is full. Fill the coolant reservoir tank with coolant, until the tank is filled to the "Full" mark.
- 8). Start the Bronco, and turn the heater control panel to full heat and defrost mode. Allow the truck's engine to run for no less than 20 minutes. Add coolant to the radiator as needed to keep the radiator full of coolant for this bleeding process. Turn the Bronco engine off once the air pockets and bubbles have completely stopped coming out of the radiator fill hole. Top the radiator off with coolant, then replace the radiator cap.
- 9). Remove the drain pan from beneath the truck. Thoroughly rinse the area of the ground beneath the truck. Empty the drain pan into an empty 1-gallon milk jug or other 1-gallon resealable container. Take the jug of coolant to your local auto shop or auto parts store, and ask them to dispose of the waste coolant.
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