How to plug a rock puncture in your radiator

First of all, get out your handy bottle of "Leak Stop", remove the cap, walk over to the ditch, and hold the bottle upside down until it's empty. Keep that junk the heck out of your coolant system. If you are a fan of "Leak Stop", or one of the other interchangable products claimming to do the same thing, you probably also use Slick 50, regularly rub special Go-Faster Oil on your tires, and should probably not read any further.

The quick and simple way of fixing a rock punctured radiator is this:

• Find the leak. Figure out how many vertical pipes are broken, and how you can get at them.
• Using a knife (or any other pointy object) open up the holes until they're at least a few milimetres across.
• Clean and dry the area in a 5mm circle around the holes.
• Get a pair of pliers ready.
• Mix up a bit (1 cubic centimetre is more than enough) of 5 minute epoxy. If you can afford to wait for it, the regular kinds give a much stronger bond, but the 5 minute stuff seems to work OK in this application.
• Using a handy stir stick, splat-push-smear some of the epoxy into and around the hole.
• Once the epoxy starts to set slightly, use the pliers to crimp the pipe closed around the hole. A bit of glue should squeeze out.
• Wait another 15 minutes, and you should be good to go.

In this fix, the hole is actually closed by crimping the pipe shut. The epoxy in this case acts only as a sealant plugging up the small gaps crimping inevitably leaves.

I've used this twice on motorbikes, and once one the Honda, and none of the leaks reoppened.

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