Can aux. heater valves be rebuilt?

[Dash01]

After replacing my heater core I inspected the old one out of curiousity.

Stuck inside were remnants of a rubber membrane with a hole in the middle. This appears to be part of the valve closure seal from the heater control valve next to the aux. heater pump.

So, can heater valves be rebuilt with new rubber? Or, must the whole heater valve be replaced?

[632 Regal]

http://www.bimmer.info/forum/showthread.php?t=28365

[winfred]

the ones that the first year or so e32s can be rebuilt but the e34 and later e32s are pretty much toast when they die

[Dash01]

the ones that the first year or so e32s can be rebuilt but the e34 and later e32s are pretty much toast when they die

Sorry to hear that. Surfing the net early today, found a reference on another website from somebody in New Zealand saying that these could be rebuilt, for around $15. I'm not sure which model BMWs this applies to, i.e. E34 or only prior models.

The seals in my heater control valve are toast, but the thing is otherwise working.

From Shogun's pictures, it appears the heater control valve can be easily taken apart for access to the seals, which apparently mate with the conical plungers to close the valves. As I understand it, the valves are default set to the open position to allow hot water from the head to automatically circulate to the heater core, and the electric solenoid-operated valves only close and cut off such hot water when actuated by the cabin heat control panel. If the seals are toast or gone, some hot engine water can flow through the valves, giving unwanted heat even when the air conditioner is on in summertime.

I wonder if some sort of thin neoprene washer could be used or modified for use as a replacement seal for the heater control valve. Anybody know?