BMW E46 Thermostat and Thermostat Housing Replacement
How do you replace the E46 thermostat housing?
1. Release the hose connector lock with a screwdriver, and the hose comes off easily. 2. The metal hose clamps open with a small flat-blade screwdriver. 3. Replace the thermostat and the housing together with new ones. 4. On a cold engine, the stick in the bleed window must rise to its pin, otherwise air gets into the circulation. The job can be done in a home garage.
Can you replace the E46 thermostat without replacing the whole housing?
On M52 and M54 engines the thermostat alone can be replaced without removing the housing. An aluminium housing is also available to replace the old plastic housing. A colder thermostat suits track driving better than street use.
What temperature should the E46 engine warm up to?
With a working thermostat, the coolant temperature on the 320d is about 88–92 °C. On the E46 M43 1.9 engine the thermostat opens at 105 degrees. If the water does not warm up, check the bleeding and the condition of the water pump.