Mk2 Golf - Leaking radiator

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Sat 2 Jul 2011 14:33
Mk2 Golf - Leaking radiator - golf-driver

I have a Mk2 Golf with a 1300 engine.

There is a moderate coolant leak from the sidewall of the radiator, where the mesh meets the plastic sidewall. The radiator is a replacement from the first, it is 6 years old.

The leak rate does vary, the worst case is losing 3/4 of a pint in a week / 100 miles

Will RADWELD work here? I have read that there are negative side effects.

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Sat 2 Jul 2011 14:54
Mk2 Golf - Leaking radiator - Peter.N.

If you can afford a new radiator that would be by far your best option - or even a secondhand one if you can find a good one.

Radweld may effect a temporary cure in an emergency but it may also clog the heater matrix. If you have to keep topping it up you are loosing antifreeze, that isn't good for the engine either because of the corrosion inhibitors it contains.

There is new one here for £35.00 inc delivery:

http://www.ebay.co.uk/itm/Radiator-VW-Golf-Mk2-1-6-1-8-GTI-16v-430x322mm-NEW-/310298855223?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item483f40c737

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Sat 2 Jul 2011 16:02
Mk2 Golf - Leaking radiator - piston power

Take it to a radiator specialist and ask how much for a repair.

They can weld plastic, alloy, and save you a few quid.

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Mon 4 Jul 2011 00:17
Mk2 Golf - Leaking radiator - golf-driver

I have noted the helpful advice.

After driving I have checked the coolant system when it was hot, the radiator was more or less dry. I only see coolant a day after when everything is cold, I also see some coolant under the bypass valve.

There is a lot of lime scale around the coolant pipe connection to the carb housing, again though it is dry after checking when driving and when cold. Could this be the main source of the coolant leak?

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Mon 4 Jul 2011 03:26
Mk2 Golf - Leaking radiator - unthrottled

Highly likely. Those hoses will be pretty old by now and it wouldn''t be surprising if one had stated to perish. Could be losing coolant when you drive and the system is pressurised, whereas at idle there isn't sufficient pressure to open up a split. Radiators are generally pretty good unless only used for short journeys and corrosion can eat them away.

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Mon 4 Jul 2011 08:10
Mk2 Golf - Leaking radiator - jc2

Exchange rad from Serck.

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Sat 16 Jul 2011 16:38
Mk2 Golf - Leaking radiator - golf-driver

I have sorted the minor leaks from the hoses, these were not the problem.

There is no oil in the coolant expansion tank.

After driving and with engine running I noticed steam coming from the radiator mesh, this could explain why I do not see coolant leaking. I this a common thing? The radiator is only 6 years old (27k miles) but not a genuine part and most of my journeys were short.

Will a basic radiator like the http://cgi.ebay.co.uk/VW-Golf-II-MK1-MK2-Jetta-78-91-1-0-1-3-radiator-manu-/170273937621 be good enough or will this also start to eventually leak?

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Sat 16 Jul 2011 16:46
Mk2 Golf - Leaking radiator - unthrottled

If there are any scrappies in your area, give them a call. I got a great radiator for £20 a few years ago.£30 is fine, but postage bumps it up to £50 which isn't so great.

It' is common for radiators that seldom get hot to corrode and start leaking.

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Sat 16 Jul 2011 18:28
Mk2 Golf - Leaking radiator - golf-driver

Forgot to say that there is no corrosion on the radiator aluminium mesh, it almost looks new.

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Sat 16 Jul 2011 22:43
Mk2 Golf - Leaking radiator - Peter.N.

The reason you don't see any water when its hot is probably because its evaporating as fast as its leaking out.

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Sat 16 Jul 2011 22:58
Mk2 Golf - Leaking radiator - unthrottled

...and when it isn't hot there isn't enough pressure to force the coolant through what is probably a very small hole.

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Sun 17 Jul 2011 00:00
Mk2 Golf - Leaking radiator - Chris M

Stick some Radweld in. I've used it several times with no adverse effects on older cars I've owned.

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Sun 17 Jul 2011 23:16
Mk2 Golf - Leaking radiator - Big John

I used Radweld a few years ago on an Austin Allegro - fixed the radiator for a few weeks but the heater never worked again!

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