How to Replace the Thermostat on the 2000 Audi A4
- 1). Remove the bolts that secure the engine skid plate to the bottom of the engine using a socket and ratchet. When you remove the skid plate, you will expose the bottom of the radiator and the water inlet housing.
- 2). Remove the red radiator pug with a pair of pliers and drain the contents of the radiator into a drain pan. Push the red plug back into the radiator after you are finished.
- 3). Follow the lower hose to locate the water inlet housing. The hose connects to the housing.
- 4). Remove the two nuts that secure the water inlet housing to the water pump using a socket and ratchet. Pull the housing off the water pump while still attached to the hose. Wipe the mating surface of the cover off with a clean towel.
- 5). Pull the old thermostat out of the pump.
- 6). Place the thermostat gasket onto the housing of the new thermostat. Coat the surface of the gasket with coolant.
- 7). Slide the thermostat back into the water pump. The end of the thermostat with the spring goes into the pump.
- 8). Place the water inlet housing onto the water pump, thread the nuts back onto the water pump studs and tighten them with the socket and ratchet.
- 9). Open the radiator cap, place a funnel into the filler spout and drain the coolant back into the engine.
- 10
Place the engine skid plate against the bottom of the engine, thread the bolts into place and tighten them with the socket and ratchet.
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