Necessity improving heater valve

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thomas_m535i
Posts: 98
Joined: Tue Jul 21, 2009 7:22 am
Location: The Netherlands

Necessity improving heater valve

Post by thomas_m535i »

I've replaced the water (heater) valve. Yet, I remember discussions about a possible diminished strength/integrity of the updated heater valve design. This could lead to a higher chance on coolant leaks. Heater valves comprise two halves. The original type of heater valve is indeed merged together.
You can indeed see on the picture that the updated design uses two clamps.
Also, more worryingly, you can see that there is a small gap between the two halves.

http://img43.imageshack.us/img43/5829/img0139mf.jpg

My question is: is this indeed a point of concern and should I make it more solid and leak proof. For instance by using silicon adhesive two seal off the seam between the two halves?

Please let me know if you've experiences with this issue. Good advice is of course also welcome.
E12 M535i '80 (currently restoring)
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Mike W.
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Joined: Wed Aug 30, 2006 12:12 am
Location: Sonoma County

Post by Mike W. »

I'd heard of the new ones but your pic is the first I'd seen it so I have no first hand experience. But silicone isn't nearly strong enough, it won't do anything. Now epoxy would help, it's strong and hard. As to if it's needed or not I can't say, but I have heard of failures with the new ones besides just the O ring leaking after 200K miles.
Mike W.



02 525ita. Wife's, aka grocery getter
02 530i. New to the fleet, 3 pedals.
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thomas_m535i
Posts: 98
Joined: Tue Jul 21, 2009 7:22 am
Location: The Netherlands

Post by thomas_m535i »

Thanks Mike, that's a very good idea. About the O-rings: replaced those as well and hope they will indeed last 200K miles... to increase my chances I also used a liquid gasket as an extra sealant.
E12 M535i '80 (currently restoring)
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