Heater control valve

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Blaise
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Heater control valve

Post by Blaise »

So, I finally had the chance to remove a heater control valve. Thanks BMW for thinking about the guy who maintains the car :)

Those nuts are not exactly the best shape to grab blindly.

I did notice that in the FAQ, one replaces the O-rings at the inlet and outlet pipes. Mine don't even look like o-rings anymore.

But in my case, the valve was leaking at the control end. I assume that there is another o-ring that seals that green control socket.

Has anyone ever changed this? Can one open the valve and reseal it properly?

Based on what I see and what a pain it is to get in and out, I am guessing that it is best replaced with a new unit.
1977 BMW 530i
1973 R75/5 BMW (motorcycle)
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Mike W.
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Post by Mike W. »

No, the O ring that leaks is burried in there, not replacable as far as I can tell. I pulled so hard on the part that turns one time I broke it off, but I still couldn't get in there. As you have found out, it is arguably the worst job on the car. And between E12s, 21s and 24s I've done about a half a dozen. It doesn't get any easier with practice, you just know you will get there eventually.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
joe_keefer
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Post by joe_keefer »

oh great,

let me guess... my car likes to steam up the windows after i get done driving. nothing crazy, can`t smell coolant or anything. would this be a symptom that leads to me having all this fun? is it something that is a sooner than later project also?

thanks in advance, joe
Bones heal, pain goes away, and chicks dig scars!


1979 528i 500k+ miles "betsy" 2nd owner!
1994 Vw Golf 234k starts everytime!
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Mike W.
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Post by Mike W. »

Steaming up windows would be a leaky heater core, not the heater valve, it just drips down onto the carpet. But the lack of an anti freeze odor is a good thing, believe me a very good thing. You would be looking at pulling the whole heater assembly, not just the valve, and it's only accessable after pulling the A/C. And the console. The dash can stay though.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
03 QX4, AKA the Datsun. Finally got the 4WD vacationmoble to stop smoking.
07 Xterra. Still on the DL, a purchase from hell.
joe_keefer
Posts: 58
Joined: Tue Sep 28, 2010 1:13 pm
Location: Portland, Oregon

Post by joe_keefer »

Mike W. wrote:Steaming up windows would be a leaky heater core, not the heater valve, it just drips down onto the carpet. But the lack of an anti freeze odor is a good thing, believe me a very good thing. You would be looking at pulling the whole heater assembly, not just the valve, and it's only accessable after pulling the A/C. And the console. The dash can stay though.
well thats good i guess. i forgot to mention that i haven`t had to add any coolant either. so it must be a small leak at this point.
Bones heal, pain goes away, and chicks dig scars!


1979 528i 500k+ miles "betsy" 2nd owner!
1994 Vw Golf 234k starts everytime!
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Blaise
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Post by Blaise »

joe_keefer wrote:
Mike W. wrote:Steaming up windows would be a leaky heater core, not the heater valve, it just drips down onto the carpet. But the lack of an anti freeze odor is a good thing, believe me a very good thing. You would be looking at pulling the whole heater assembly, not just the valve, and it's only accessable after pulling the A/C. And the console. The dash can stay though.
well thats good i guess. i forgot to mention that i haven`t had to add any coolant either. so it must be a small leak at this point.
Just take a look at the valve. If it is leaking, you likely will see a little drip hanging from it. The valve is directly above the gas pedal. Also, check the carpet and padding around the gas pedal. Try to get your finger around the gas pedal and into the padding below....you should feel the moisture if there is any. If there is....lift the carpet and get it all dried up.

If the valve is leaking, you can disconnect the coolant hoses in the engine compartment and hook them to an elbow (buy) to loop them back into the engine. I did this on my car until I replace the valve.

<table><tr><td><a href="https://picasaweb.google.com/lh/photo/u ... site"><img src="https://lh5.googleusercontent.com/_UZQu ... C09836.JPG" height="300" width="400"></a></td></tr><tr><td>From <a href="https://picasaweb.google.com/1030509870 ... tr></table>
1977 BMW 530i
1973 R75/5 BMW (motorcycle)
joe_keefer
Posts: 58
Joined: Tue Sep 28, 2010 1:13 pm
Location: Portland, Oregon

Post by joe_keefer »

Blaise wrote:
joe_keefer wrote:
Mike W. wrote:Steaming up windows would be a leaky heater core, not the heater valve, it just drips down onto the carpet. But the lack of an anti freeze odor is a good thing, believe me a very good thing. You would be looking at pulling the whole heater assembly, not just the valve, and it's only accessable after pulling the A/C. And the console. The dash can stay though.
well thats good i guess. i forgot to mention that i haven`t had to add any coolant either. so it must be a small leak at this point.
Just take a look at the valve. If it is leaking, you likely will see a little drip hanging from it. The valve is directly above the gas pedal. Also, check the carpet and padding around the gas pedal. Try to get your finger around the gas pedal and into the padding below....you should feel the moisture if there is any. If there is....lift the carpet and get it all dried up.

If the valve is leaking, you can disconnect the coolant hoses in the engine compartment and hook them to an elbow (buy) to loop them back into the engine. I did this on my car until I replace the valve.

<table><tr><td><a href="https://picasaweb.google.com/lh/photo/u ... site"><img src="https://lh5.googleusercontent.com/_UZQu ... C09836.JPG" height="300" width="400"></a></td></tr><tr><td>From <a href="https://picasaweb.google.com/1030509870 ... tr></table>

wow, thanks for the info.! the pic. will likely be a big help to. thanks a lot.

joe
Bones heal, pain goes away, and chicks dig scars!


1979 528i 500k+ miles "betsy" 2nd owner!
1994 Vw Golf 234k starts everytime!
T.Hanson
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Post by T.Hanson »

If you are replacing it just never forget it can be done. Do read the FAQ, get the tool recommended and don't lose the nuts.
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Blaise
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Post by Blaise »

Here is a tip for those who want to be sure that their heater valve does not leak.

I had not seen any signs of leaking in the heater valve in my parts car, so installed the valve in my good car.

But, I also added a quart size ziplock bag underneath and kept the kick panel off for a few weeks of observation.

Sure enough, I found a few drops of coolant in there. It would likely not have been perceptible without the bag.

<table><tr><td><a href="https://picasaweb.google.com/lh/photo/j ... site"><img src="https://lh3.googleusercontent.com/_UZQu ... Valve1.JPG" height="400" width="299"></a></td></tr><tr><td>From <a href="https://picasaweb.google.com/1030509870 ... tr></table>

<table><tr><td><a href="https://picasaweb.google.com/lh/photo/9 ... site"><img src="https://lh3.googleusercontent.com/_UZQu ... Valve2.JPG" height="400" width="299"></a></td></tr><tr><td>From <a href="https://picasaweb.google.com/1030509870 ... tr></table>

Now I get to wrestle with those nuts again.
1977 BMW 530i
1973 R75/5 BMW (motorcycle)
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