OK this is a hole not corrosion but it shows how to do it. He gets it really clean and that is the trick and the problem with corrosion if its hard to get to good metal.
 
That's good Rob, I would suggest that you can dry out the water with a hot air blower much more thoroughly than trying to get it all with rags. You can get them so hot that no water could survive in there. Also a big soldering iron, (as opposed to a small soldering iron) is a better way to get the job done and make a much neater finish with no solder running in rivers all over the tank.
 
That's good Rob, I would suggest that you can dry out the water with a hot air blower much more thoroughly than trying to get it all with rags. You can get them so hot that no water could survive in there. Also a big soldering iron, (as opposed to a small soldering iron) is a better way to get the job done and make a much neater finish with no solder running in rivers all over the tank.

Lot of effort to save a hundred quid, and it is highly likely the tank will rust through elsewhere in short order.
 
Lot of effort to save a hundred quid, and it is highly likely the tank will rust through elsewhere in short order.
Quite right, and with Land Rover tanks often leaking at the seams or somewhere in the bottom where there are two layers making it impossible to find and repair, not a practical proposition. But, where it is possible - useful knowledge.
 
First run with the patch on seems to have gone ok. I left it 24 hrs to set up. Then 12 hours with some fuel in the tank and a clean rag underneath to test for drips. No drips and no seepage. First drive went fine. I’ll be keeping a very close eye on it and I’m still fairly sure there is a new tank in my near future.

CCDFFED0-13F7-454B-9BFC-D42976563271.jpeg

NB - that’s not a bubble - I used two layers of the epoxy.
 
I would normally agree with the others about it being a lot of trouble to save £100 especially considering the effort of getting it out. On the other hand, if new tanks don't fit.....

Col
 

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