Author Topic: Heater valve joint repair  (Read 4063 times)

PeterPortugal

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Heater valve joint repair
« on: August 31, 2015, 16:51:21 »
Hi All,

I finally got around to pressure testing my heater cores properly. Thanks to all who advised on this.

I discovered that one core is leaking where the valve body is joined to it.

is repairing this joint a specialist job? I know a plumber who solders copper tubing all day long and thought that this might be something he could tackle.

I also know a local radiator repair shop but I wasn't sure how relevant heater cores are to regular radiators.

Any advice would be welcome.

Regards

Peter
1963 220se Cabrio
1968 280se Coupe

Bonnyboy

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Re: Heater valve joint repair
« Reply #1 on: September 01, 2015, 13:44:06 »
I offer a third alternative - find someone who works on refrigeration and ask them if that is something they can fix.

I have found those guys to be much more careful in brazing (rather than soldering) and being able to identify the different metals and corresponding brazing materials needed to make a lasting repair.

Ian
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tel76

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Re: Heater valve joint repair
« Reply #2 on: September 01, 2015, 14:25:38 »
If you are brazing you add a lot of extra heat this will melt all the soldering that holds the item together.
With brazing you are using brass rods and a flux,  the item you are brazing has to be cherry red to obtain the correct temperature to melt the brass and effect the repair, if you do this you will melt all the solder that holds the radiator together.
If you cannot undertake the repair yourself wit solder take it to a radiator repair facility.
Do not braze use solder.
Eric

PeterPortugal

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Re: Heater valve joint repair
« Reply #3 on: September 01, 2015, 14:34:54 »
Gents.
Thanks for your responses.
Eric - is a plumber up to this do you think? I know him well and he can speak English. The radiator repair man only speaks Portuguese (and I do not) so he is more "risky".
Cheers
Peter

1963 220se Cabrio
1968 280se Coupe

Cees Klumper

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Re: Heater valve joint repair
« Reply #4 on: September 01, 2015, 18:24:36 »
Years ago I re-soldered the purge tap at the bottom of our radiators, just with normal solder, low heat etc. Some 10 years later it's still fine. I would not hesitate to ask anyone who is reasonably competent with soldering so including your plumber (myself I am not really that experienced at all) to fix it. How much for a new one?
Cees Klumper
1969 Mercedes 280 SL automatic
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PeterPortugal

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Re: Heater valve joint repair
« Reply #5 on: September 01, 2015, 19:05:07 »
Thank you Cees. The plumber it is !!!
1963 220se Cabrio
1968 280se Coupe

Bonnyboy

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Re: Heater valve joint repair
« Reply #6 on: September 02, 2015, 02:45:11 »
Excellent - I learned something too today.   

Thanks all.
Ian
69 280SL
65 F-100
73 CB750K
75 MGB
78 FLH
82 CB750SC
83 VF 1100C
94 FLHTCU
08 NPS50
12 Pro 4X

tel76

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Re: Heater valve joint repair
« Reply #7 on: September 02, 2015, 08:26:18 »
The only reason I suggested the radiator shop is that he is familiar with car radiators and he has the facility to pressure test the rad: after he has carried out the repair.
You should have it pressure tested (there could be another weak spot), you would be very annoyed if you were to refit the rad: and find it leaks, better safe than sorry.
Eric

PeterPortugal

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Re: Heater valve joint repair
« Reply #8 on: September 02, 2015, 10:43:54 »
Hi Tel76,

I couldn't agree more. I tried a few different ideas but could never convince myself 100% that everything was OK. I stripped my heater down again and did it properly and found a leak - I was almost "glad" !!

Other members gave me some great suggestions for DIY pressure testing.

The technique which worked best for me was to cut a section out of a bicycle inner tube. Fold back the two ends by an inch or so to create "cuffs" for a bit of extra strength and fit to each end of the heater using hose clamps. I also fitted a short section of hose on each heater connection to increase the diameter to a suitable size. Blow up the inner tube until it is filled out with a bit of pressure and then wrap it in duct tape to prevent it expanding further. Once you have done this you can increase the pressure without the inner tube bursting.

Place the heater core under water and look for bubbles.

Peter
1963 220se Cabrio
1968 280se Coupe