2. Locate the thermostat housing. On the Mercedes 450 SL, the thermostat housing is located on the front of the engine, near the top. It is a round, metal housing with two hoses connected to it.
3. Remove the two bolts that hold the thermostat housing in place. Be careful not to drop the bolts into the engine.
4. Lift the thermostat housing off the engine. The thermostat will be located inside the housing.
5. Remove the thermostat from the housing. Be careful not to damage the thermostat gasket.
6. Inspect the thermostat for damage. If the thermostat is damaged, it will need to be replaced.
7. Install a new thermostat, if necessary. Make sure to install the thermostat gasket properly.
8. Reinstall the thermostat housing and the two bolts.
9. Close the hood of the Mercedes.
