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Radweld - is it worth trying? - Cambridge
N reg VW Passat.
It has a minor coolant leak from somewhere.
The reservoir drops from max to min over about six months.

Is Radweld worth trying?
Will it work OK in a VW, as I understand they use a special coolant.

Thanks for your help.
Radweld - is it worth trying? - Stuartli
You don't have to use the special coolant in a VW - if you do there's no need to change it, whereas the ordinary coolant has to be changed every two years.

I can't see any harm in using RadWeld. I used it in cars in the past and it's saved the cost of buying a new one on more than one occasion.

It must be a very small leak indeed to take so long to go from max to min, so you should first check that all the hoses etc are firmly connected.
Radweld - is it worth trying? - Civic8
I would put that down to evaporation rather than a leak.but how often do you check levels?.I think if you had a leak it would have lost a lot more and in a shorter time
Was mech1
Radweld - is it worth trying? - frostbite
Save your money - you don't really have a problem, but Radweld might start one.
Radweld - is it worth trying? - Mark (RLBS)
If you have a small leak you can pick and choose when and how to repair it.

If you use radweld and it ever lets go, it will be a big leak with correspondingly less time/choice about the repair - i.e. none.
Radweld - is it worth trying? - Dynamic Dave

Radweld gets my vote. Out of all the times I've previously used it, only once it didn't work, which is mentioned in this link.


Radweld - is it worth trying? - Aprilia
Used car dealer swear by it.....
Radweld - is it worth trying? - Simon
It drops from max to min over a period of six months...? I wouldn't consider this to be a problem. Surely it can only be a matter of half a pint or so, and I would think a passat has quite a large capacity coolant system anyway. I think that putting radweld in will do more harm than good.
Radweld - is it worth trying? - Mike M
I've used radweld for years and had no problems. However, you may not have a problem. The coolant on my wife's Polo needed topping up from Min to Max every few months. I could find no leak anywhere, so left it to see what it would do. The level did not drop below the Min mark and it has stayed on Min ever since. The system seems to have expelled the excess through the pressure release valve and it was only when I examined the valve closely did I see the tell-tale pink crystals of antifreeze around it.

Radweld - is it worth trying? - Sofa Spud
My L reg Passat had a small radiator leak and I put some Radweld in. It fixed the problem for over a year, although the radiator did fail eventually and had to be replaced.

Cheers, SS
Radweld - is it worth trying? - Civic8
Some points relate to a leak.point was made over six month period.unless any one expects levels to stay the same in this time.would think they are wrong.too many variants to say it is correct.My previous post stands.
Was mech1
Radweld - is it worth trying? - Sprice
I used Bars stop leak once in my diesel astra (Isuzu engine), and it must have blocked a channel or something as the car started overheating after a couple of minutes and I had to get rid of it.
Radweld - is it worth trying? - JH1
I've tried rad weld once, with no joy. So when i had a leak problem on my Golf 2 GTi, I tried a Sodium Silicate (water glass) based product. It worked a treat and the leaks stopped. You have to flush the coolant, fill the system up again, with the stuff added, run it for half an hour, then drain the excess and leave to stand for 4-12hours to harden. Then you fill up with water and anti-freeze and away you go.

However, I started loosing water again recently (after 12months) which turned out to be from the heater matrix as mentioned in a different thread. I had already bought another bottle of the stuff (approx £10), trying not to have to change the radiator.. but then realised the real cause.

I now have the a spare bottle of the stuff. I will check its name and put it on here tomorrow.
Radweld - is it worth trying? - JH1
...continued from last post: It is called "Liquid glass metallic Seal Up" By CarGo

Worth a go and dont know of any chance of doing damage like blockages etc..
Radweld - is it worth trying? - Cambridge
Thanks to everyone for the suggestions.

I am going to do nothing! monitor the situation and see if I can locate the cause of the loss.

Radweld - is it worth trying? - Spanner
See if you can get the cooling system pressure tested. Radweld and similar products are all good emergency 'get you home' type treatments but they don't cure the cause of the leak - only the symptom. If you intend keeping the car for a length of time and want the normally reliable Passat to remain reliable, then find the cause as it will eventually get worse. A pressure test will normally produce leakage from somewhere and if not then suspect the coolant expansion tank cap. These do wear out due to constant cycling of heat, cold and pressure. Waterpumps can leak intermittently under the timing belt cover where engine heat evaporates any traces.
Radweld - is it worth trying? - Mapmaker
A new radiator cap may solve your problems. They too wear out. £2.50.

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