Radweld???

Author
Discussion

Moto

Original Poster:

1,238 posts

254 months

Tuesday 16th April
quotequote all
I have the smallest weep of dampness on the bottom brass tank of the original radiator. It's been like this since I had the radiator recored 5 years ago. It doesn't drip or ever need coolant topping up it's that small, however it annoys me and I want to fix/replace it.

I've Googled Radweld type products and they seem to have a pretty poor reputation for clogging up waterways, particularly in old heater matrix. However I'm thinking such a slight weep (probably a 'not perfect' braze or something similar) that has got no worse over 5 years, could this be a perfectly good solution to the problem. Or do I bite the bullet and take out the radiator to either re-braze or replace?

Moto

Granturadriver

581 posts

262 months

Tuesday 16th April
quotequote all
Removing and re-soldering is certainly the better method. But I have also used the product before and used it to seal a leaking cylinder head gasket. It worked and lasted for several years until the gasket was replaced during an engine overhaul.

5.0ltr

2,763 posts

200 months

Tuesday 16th April
quotequote all
All I can say about that stuff is it left me overheating on the M62 in a blizzard without any heat for the car in a convertible with a particularly frosty girlfriend. Up to you.
Never used it again, I replaced the radiator later.

phillpot

17,117 posts

184 months

Tuesday 16th April
quotequote all

Radweld and similar products work by "setting" when exposed to air, i.e. when they come out the leaky hole.

There is no reason they should clog radiators or heater matrix.

I had a similar very slight weep on my Taimar radiator, don't tell the guy who bought it but this sorted it without issue for years wink


keynsham

273 posts

272 months

Tuesday 16th April
quotequote all
I have used Radweld (and Bars Leaks) in a lot of old vehicles over the years and never had an issue with it. If it is clogging up pipes, then I suspect the pipes in question are already half clogged to begin with as the additive in it should only collect at locations of very small leaks. I just used a bottle to stop a weep on the 350i radiator and it has worked fine as always!!..... and a lot cheaper and less hassle than a replacement or re-cored radiator job!

cjb44

681 posts

119 months

Tuesday 16th April
quotequote all
I have used Bars Leaks with success on many old brit cars without any problem, would I dare do it on a TVR I am not so sure.

P100

619 posts

207 months

Wednesday 17th April
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I have had mixed results with Radweld.
Ive always looked at it as a solution to a breakdown rather than a long term fix.

These days I use Forte leak stop which seems a much more friendly product, and it doesnt clog up your radiators or heater matrix.

Let me know if you want some as I keep it in stock.

Adrian@

4,313 posts

283 months

Wednesday 17th April
quotequote all
Steve, IF you want a core radiator to work on whilst your car still runs, then email me a picture of what you have (I will check it against the ones I have) ..it will cost you a donation to my chosen charity. A@

Moto

Original Poster:

1,238 posts

254 months

Wednesday 17th April
quotequote all
Thanks Adrian@ and all the responses. Interesting feedback with a mix of good & not so good experiences.

I think I'll probably go down the safe route - remove, inspect & braze / replace. It's probably the only way to be sure I don't kick the can down the road for it to return at an inconvenient moment.

Moto