Can e12/e24 heater valves be rebuilt?

[540i]

I was looking at price quotes for parts for my project this spring (clutch cylinders, door handle, heater valve for my '79 635csi), and noticed that this particular part supplier was selling replacement o-rings for heater control vavles:


http://www.autopartswarehouse.com/sku/B ... Drivetrain


I'm not familiar with this website and usual sixer distributors such as Bavauto, Autohauz, and pelican parts have nothing but the uber-pricey heater valve.

Has anyone tried to replace the o-rings in their old heater valves, and did they work? I'd hate to spend $80-120 on a heater valve when the only thing leaking is an o-ring!

[Wil]

Yes ,I did rebuild mine and is very simple inside.
What keeps the coolant from coming out is 3 o rings in diferent places.
But I didn't put it back , I started to think about how much work was to remove and install, that I bought a new one.
Also if you are going to rebuild it make sure that you use clips to hold the 2 parts of the valve body together, I know that it may come appart under pressure
Hope this helps
Wil

[540i]

Good to know thanks.

I have quite a bit of work needed on my 540i (typical 100k miles stuff) and the fact my wife and I are going to build a home makes me think I might try the rebuild. I have two valves, so I'll be able to test the rebuild for free (first valve was shipped free to me from a member of bigcoupe.com to attempt a rebuild) so I'll be able to attempt a rebuild without removing the valve.

If I had the $$, new valve no question, but I may attempt to rebuild this thing.

What type of clips did you use to seal it?

[T.Hanson]

If you are referring to the valve over the gas pedal, the fix is a new valve. There is a FAQ on the subject and you can Google Search it here for more swearing.

No matter how impossible it seems, wedging your head under the pedals to see (only with one eye ), how teeny the icky little nuts are, and odd, so don't lose any, it can be done.

Even though I've done it, I would rather have the engine seize than discover coolant dripping on my shoe again.

[Mike W.]

Yes ,I did rebuild mine and is very simple inside.
What keeps the coolant from coming out is 3 o rings in diferent places.
But I didn't put it back , I started to think about how much work was to remove and install, that I bought a new one.
Also if you are going to rebuild it make sure that you use clips to hold the 2 parts of the valve body together, I know that it may come appart under pressure
Hope this helps
Wil

How did you even get it apart? I've tried, and the solvent cement they use beat me. I might have been able to get it apart, but not to then again get it together without leaking. Are you talking the new kind? I've heard they came out with a new higher priced version that may be repairable.

[540i]

on www.bigcoupe.com there is a post called "exploding heater valves" where apparently the new kind is connected by clips instead of cement. Forum members were noticing that at BEST coolant was dripping on their shoe again shortly after the change, and at WORST the valve actually bursting and dumping coolant everywhere.

One person actually had to have BMW service replace his stereo head unit because enough coolant escaped when it burst (second valve to burst in his car) to damage the electronics in the center console area.

Some members were going through 3 or 4 valves (who wants to do that job back-to-back-to-back-to-back) before figuring out hodgepodge ways of securing the valve against bursting.

One member went so far as to connect a 5 series cable-driven valve and convert it to shaft control. He's never been back to the forum to tell us how to do it.

Anyway, read it for yourself:

http://bigcoupe.com/phpBB2/viewtopic.ph ... =exploding


My valve appears to be leaking at the o-ring on the interior side of the car, exterior of the valve. My hope is to use the rebuild kit and squeeze the new o-ring in without removing the valve. Might be worth a shot if the O-rings are the right size.

What I don't want to do is buy a new valve, as no one has yet verified if the bursting problem has been fixed. I'd rather repair and old one.

[Wil]

You can not replace that o ring without taking the valve appart, the o ring seats in the inside part of that interior wall.
May be you can squeeze another one from the outside but I dont think so
I had done a new valve in november and I have around 1000 miles without any problem
The old one had the body glued together, but the new one came glued and with clips holding the 2 pieces of the body together
I think that the people with problems with those valves also had a problem with too much pressure inthe cooling system,

[Wil]

Hey mike sorry I didn't see your post.
I remember grinding or cutting the lip and then prying the body appart with a screw driver,
then i used J&B weld to glue it back on.
Didn't have the chance to try it

[1st 5er]

Is the part in question, #1?

It's leaking on my car, but just enough to get a smell.

I've got a used one to try out.

Please keep us posted if you go the rebuild route.
I'm up for saving 100 + $$$, if possible.