Bmw E30 Heater Valve Leaking

Water entering from under the floor.

Bmw e30 heater valve leaking.

If the bmw e31 has a weak spot it s the cooling system. The heater valve can also break if an incorrect radiator cap was fitted. Water entering through the heater ac box. You will need to replace the two o rings that reside between the valve and the core.

This feature is shared with the e32 and e38 but one thing that isn t is the restorative heating there s no rest button in the e31 and the auxiliary water pump appears superfluous. Rebuild is a very simple process. A quick check would be to confirm hot coolant is entering the valve at the upper hose red arrows and into the heater core through the lower hose green arrow. The heater valve connects the matrix to the stub pipes and its joints and o rings can break down over time.

It s a simple if fiddly fix made a lot easier by removing the glove box. In particular the heater valves get stuck or blocked hoses explode the auxiliary pump seizes up leaks and then the end drops off. It then flows through the valve out the bottom to the heater core green arrow. This is the cause of 99 of wet passenger footwell issues.

I was able to change both on my 325ic. Why buy a new valve when the brass part does not wear out the kit includes everything but the brass shell. There is a good article on how to replace the the value and heater core. I have gone through a few heater valves.

Guts break replace whole valve with another used valve repeat. Hot coolant flows from the engine crankcase to the valve. This time i bought a rebuild kit from blunttech. Make sure that you do not have a rust through area in the floor.