Radiator leak

[John]

Anyone had any experience of using radweld or anything to seal a small leak in a radiator? Will it stand antifreeze come winter?
Anyone any ideas
Thanks
John

[Wonko_The_Sane]

I don't use radweld. It's purpose is to block holes and small leaks..but it can't differentiate beteen those and small waterways sometimes.

There is a real chance of it radwelding the heater matrix, and blocking it.

I used it on a Reliant 850 engine last year..chronic overheating followed and on removing the cylinder head, some of the between cylinder water channels were blocked solid and needed a drill to open them back up.

It's better to get a replacement scrappie rad, IMO. Easy to replace, and shouldn't take longer than 30 minutes tops..:)

[MaestroMatt]

I used to use Radweld but don't now - it does stop the radiator leaking, but it dramatically reduces the heat from the heater. Far better to fix the problem itself. If the leak is in the radiator itself, rather than any surrounding pipes, you can fix it with epoxy resin - drain the radiator and take it out (easy 10 min job) and mix up a great deal of epoxy and squidge it into the area around the leak, getting it into all the nooks and crannies from both sides. Leave it to go off overnight and it will probably have fixed the leak. If not, you are no worse off!

See number 11 on this list of bodges that don't work with a couple that do:
http://bangernomics.tripod.com/bodges.htm

[John]

Is Araldite the type to use. I've gone off the radweld idea, thanks for the advice.

[MaestroMatt]

Yes. Somewhere else on Bangernomics he repeats the tip and says Araldyte is the thing to use. Hope it works - post your results!

[e692wtt]

A neighbour of mine has a Sherpa pickup with a B-series 1800 Diesel... it blew a core plug and using 3 raw eggs has stopped the leak (with the proviso that the expansion cap isn't properly tightened). He adds another egg every couple of weeks and reports no problems whatsoever...

Worth a try? Or will it end up with egg on face???

The other other Rich.
:laugh:

[H48HPE]

my advice here would be to go to the scrap yard and get a second hand radiator - 5 to 10 quid probably (or get a new one for £40). change it over, which is half an hour to an hours work. before you change the radiator run some flushing fluid through the sytem and then drain it off. then re attach everything and fill it up with normal water. run it till the fan comes on and then drain again. then put the new radiator on ( which should be flushed through before). when filling it up use 50 50 mix of antifreeze (i use that yellow unipart stuff). this will stop any corosion inside the system. Renewing antifreeze is important to maintain anticorosion protection.

when i first got my car the water was brown and full of crap, i flushed it out and refilled it with blue antifreeze, after the first run out it was going brown again, i couldnt be bothered to flush it again. soon after the water pump started squealing so i got a new one. before i fitted it i used the flushing fluid followed by about 4 clean water flushes and then put in the unipart stuff. now the water is the same colour as it was four months ago which is fluorescent yellow. it never lost any water before i messed with it and it hasnt dropped more than 2mm level in 4 months. its a briliant system.

sorry for the long drawn out post but i was bored

andy

[e692wtt]

I paid a tenner for a scrapyard radiator in mid-1999, and it's been fine ever since. One of the plastic 'end tanks' (the one that the top hose attaches to) began leaking THAT NIGHT where it joins the matrix, but removing the rad and 'judicious application of a pair of pliers' to make the 'end tank' fit tighter took 15 minutes and it's fime 4 years on.

Comments about flushing the system out are valid. The 1800D Sherpa engine took 50 gallons (25 watering cans) to clear the accumulated, errm, sludge, but it has been 'fairly ok' since - there were slight traces of rust where the core plug blew and the coolant was blown around the engine compartment. Being prepared to 'use and lose' Antifreeze mix is also a good idea, as the stuff 'searches out' any weak spots and collects some of the 'sludge' into the Antifreeze mix'. You will notice how much better your heater works next winter, if nothing else.

What do you use as a 'flushing fluid'?

The other other Rich.
:)

[H48HPE]

i used Holts Speed Flush

they also do rad flush but i havnt tried that one so i cant comment.

it has made a difference to the heater.

i can definitely recomend that unipart antifreeze too, its definitely put a stop to any corrosion. if you use it though, dont ever try and put it in with the blue antifreeze cos the 2 dont mix and it will cause hot spots in the engine.

andy

[John]

Couldn't get a rad from a scrappie so went with the epoxy idea and it's worked so far.
The rad was off an Astra, an alluminium one so the rad repair man didn't want to fix it.
Something about an inch long had passed through the grille somehow and damaged four tubes, three of which had pinholes in them. I pushed the fins half way down and gave the tubes a good clean with a brass wire brush, the propelling pencil type, and a wipe with meths to get any oil off. When that was dry I used blue tack to seal the area around the damage to make a sort of mould with the tubes running through it and built it up a couple of millimetres above the face of the rad and filled this with araldite, I used the standard type as I've found this to be stronger than the rapid. I left this in a sunny window for 24hrs, the Cockatiel wasn't very happy with a radiator on top of his cage but it's time he was useful! Next day the araldite was hard and I refitted the rad. I've done a short run up the motorway and a 30 mile trip and it's OK at the moment. I haven't got a thermostat in at the moment so that will be the next critical stage, do it next weekend. After that will be the addition of antifreeze in the winter so fingers crossed it will survive and thanks for all the advice.
Sorry to ramble on,
John