Bmw E30 Heater Valve Leaking

This is the cause of 99 of wet passenger footwell issues.

Bmw e30 heater valve leaking. The heater valve can also break if an incorrect radiator cap was fitted. It then flows through the valve out the bottom to the heater core green arrow. Guts break replace whole valve with another used valve repeat. I was able to change both on my 325ic.

If the bmw e31 has a weak spot it s the cooling system. 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. Hot coolant flows from the engine crankcase to the valve. You will need to replace the two o rings that reside between the valve and the core.

The value and heater core are separate components. I have gone through a few heater valves. 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. Water entering from under the floor.

If the wetness is not from engine coolant we have a few possibilities. The heater valve connects the matrix to the stub pipes and its joints and o rings can break down over time. In particular the heater valves get stuck or blocked hoses explode the auxiliary pump seizes up leaks and then the end drops off. Rebuild is a very simple process.

Water entering through the heater ac box. This time i bought a rebuild kit from blunttech. There is a good article on how to replace the the value and heater core. Make sure that you do not have a rust through area in the floor.