Hullo lads, I've got a steam system running at 2lb and have a pinhole leak in one of my rads, a real fancy one too. Replacement is not really an option and disassembly will be a nightmare as it's been painted over for 50 years. Is there anything on the market I could use to patch or can this be brazed.

Hi Annan:

They make a great boiler seal... called boiler solder...just for plugging leaks in steam boilers, BUT this will not work for you as your leak is up in the radiator and boiler seal cannot get into the radiator as it stays with water in the boiler. That is, it will not join the steam to plug the readiator.

You could try to shut the system down and take a small wire brush and clean the surface that needs to be repaired. Then you could try to use some plumber's epoxy putty (see picture).. or another similar epoxy putty to plug the hole and hopefully repair this for years to come... ;)

Here, you take a two-part epoxy putty, knead the two to a uniform color and then spread and fill the hole. Use water to feather the edges down a bit... let dry and see how it goes.

This stuff can be drilled and tapped and is said to be able to withstand high pressure... so may work for you here.

After you repair, walk away for awhile... 24 hours if possible, then try it out. Let me know how you make out... OK?

Very few people can braze/weld cast iron... could call a welding shop or two, but I doubt you will get much help... Lots of talk, but doubt anyone will actually do it for you... but worth trying if epoxy putty fails... ;)

If you have more questions, ask away!

MARK