Radiator leaking from blanking cap

[dlt1518]

I've just noticed I've got this leak coming from what I now know to be a blanking cap. I've literally no idea what I need to do to resolve this though so any advice would be appreciated!

 

[kidgreen61]

Close both valves, put towel under rad, unscrew plug and wrap threads with 4-5 wraps Of PTFE tape and retighten.
Or replace with new plug from Screwfix.

 

[ianmcd]

These plugs at both ends come with o rings, but I see a lot of failures with them exactly as you have, as @kidgreen61 advises PTFE is your friend here, you will need a small bowl and a towel when you remove the plug as a small amount of water will come out even with both valves closed, but not a lot

 

[Madrab]

All I would add to the most excellent advice above is use the bleed valve on the other end to release the pressure out of the rad first, once the valves are off, otherwise with all that corrosion, all that pressure may leave the rad all at one time once the blanking plug is loosened, it could get messy.

That and use a wire brush or similar to clean all the rust off from around and in the threads before fitting the plug. A bit of white gloss paint wouldn't go amiss either to slow down the rusting.