Heater valve - will it hold water??

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stmachreth
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Post Tue Mar 17, 2020 9:37 pm

Coolant leak (more of a weep) in the passenger footwell since I bought the car, decided to tackle it before doing some decent length journeys - isn't this a popular topic!

The new radiator cap with the yellow disc is present, perhaps was replaced after the damage had already been done to the system.

Heck of a fiddly job getting the heater valve out. Thanks due to all the online advice and tips I found online.

One of the rivets had popped and the unit case had been forced apart slightly. Dried coolant all over. I drilled the rivets out and removed the solenoid. Covered in gunky coolant, the valve plunger was filled with it. Diaphragm in ribbons, and... O-rings, what o-rings?? There's a rubberised section on the pipe flange, but no o-rings.
I've ordered a repair kit from a German site including a couple of o-rings - will have to figure out where to locate those - and some nuts and bolts to replace the rivets and tighten it up again.
https://www.specialclassicparts.de/epag ... ucts/KA013

Will this repair kit make the valve watertight? Or does it rely on the diaphragm being intact? Until I can stomach buying a new valve, or a decent one pops up on here/fleabay/scrappy, I'm satisfied with the valve being open and the fan blowing a little hotter (I've only been using it to demist over winter anyway).

I understand the diaphragms were never available separately. This is proving to be a right pain in tharse! (only because I don't yet have a solution, I've actualy enjoyed getting elbow deep in Dear Wagen)

Excuse the ramble!
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BenHar
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Post Wed Mar 18, 2020 3:04 pm

It will make the valve water tight.

It does mean that the valve never shuts off but this isn't a problem.

Ben
stmachreth
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Post Wed Mar 18, 2020 9:57 pm

Thanks!
stmachreth
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Post Thu Mar 19, 2020 3:21 pm

Please could someone help me to locate the o-rings?

The larger one, is that between the diaphragm ring and the black plastic fitting?

The smaller one, I have no earthly idea. Flange-side of the black pipe, or bulkhead-side?

Any suggestions appreciated!
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BenHar
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Post Thu Mar 19, 2020 5:19 pm

The large one goes in the slot here (ignore the flat rubber washer in the picture)
20130619_161718.jpg
The small one goes here
post-13281-1423446606,0002.jpg
Ben
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stmachreth
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Post Fri Mar 20, 2020 7:26 am

Thanks Ben,
Have you used the flat black washer to replace a knackered diaphragm, by any chance? Does the 0-ring go between the diaphragm and pipework?
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BenHar
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Post Fri Mar 20, 2020 10:55 am

stmachreth wrote:
Fri Mar 20, 2020 7:26 am
Have you used the flat black washer to replace a knackered diaphragm, by any chance? Does the 0-ring go between the diaphragm and pipework?
No, the flat washer was a trial and did not work. (That's why I said ignore it.)

Ben
stmachreth
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Post Fri Mar 20, 2020 4:33 pm

I might contact the company I bought the repair kit from, but just in case you know:

Are these o-rings meant to replace the diaphragm and the little green o-ring (found tucked within the flange of the brass cylinder) ?

I ask because, when it's all assembled with the old bits included, the valve is quite a bit bigger and doesn't 'sit' right.

In fact I think the smaller o-ring they sent me is too big. It's not snug against the brass cylinder at all
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BenHar
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Post Fri Mar 20, 2020 7:11 pm

You need

1x O-ring 30x2.5mm
1x O-ring 15x2mm

and some screws to replace the rivets.

Chuck the diaphragm away.

Ben
stmachreth
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Post Fri Mar 20, 2020 7:54 pm

Cheers Ben, you've been very helpful!

Rich
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Post Sat Mar 21, 2020 1:56 pm

Im doing one this week, I used M3 x 30 screws/washers/nylocks
stmachreth
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Post Sat Mar 28, 2020 4:53 pm

Nice, how has that gone? Parts probably sourced for pence?

I'm a bit short on work space, pretty hard to work on the car comfortably at the side of a narrow residential street.

I'm happy with it being slightly warm in the cabin until I get a cheap replacement valve. Probably just drive round with no pants on, that'll solve it.
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Brianmoooore
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Post Sat Mar 28, 2020 6:59 pm

stmachreth wrote:
Sat Mar 28, 2020 4:53 pm
I'm happy with it being slightly warm in the cabin until I get a cheap replacement valve. Probably just drive round with no pants on, that'll solve it.
I've had an E30 with the valve disconnected electrically, so permanently 'on' , as a daily driver (LPG related reasons, explained in another recent thread), and the amount of heat coming from the heater when set to full cold is next to nothing.
stmachreth
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Post Sun Mar 29, 2020 4:43 pm

Good to know! Cheers
Ian325i
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Post Tue Apr 21, 2020 12:00 pm

Good morning all, I've got the leaking heater valve issue ....I've tried o pm to a few members on here who have had the same problem ,but they don't seem to be receiving my messages...does anything know where I can obtain the o rings for the heater valve body where it splits, BenHar shows two on a recent thread, any help or advice appreciated....many thanks.
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Brianmoooore
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Post Tue Apr 21, 2020 1:35 pm

Plumbing suppliers, engineering suppliers, Lidl occasionally. Type O ring into ebay.
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BenHar
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Post Tue Apr 21, 2020 6:21 pm

Pretty sure my post gave the exact sizes?

As Brian says, ebay will have thousands of them.

Ben