Radiator bleed screw

We had this one recently and my idea was to abandon the broken one and just fit a new bleed screw in the other end of the radiator.

Bob

Hi Bob,

Thanks for getting back to me, what size did you drill and tap the hole for the new bleed screw?

Thanks.

Hi Hogie,

No drilling and tapping needed just take out the blanking plug and fit a complete bleed screw assembly. Thread is usually 1/2" BSP but there are other sizes here

hth

Bob

Thanks bob, but the radiator that i have is one of the really old style ones there is no blanking plug on the other end, its a sealed radiator

Hogie

Does it have a flat welded-in plate at the opposite end, or is it just rounded over?

If it's a flat surface, you may be able to drill and tap it and fit a bleed assembly. The smallest one listed in

If there isn't a flat surface at the end, you could drill and tap the back face of the radiator, just down from the top. It's a bit awkward bleeding it in that position - but not impossible. Indeed, some modern radiators have the bleed screw factory fitted on the back!

in

thanks roger,

but the radiator that i have has no flat surface on the end of it, the bleed screw that i damaged is at the back of the radiator, what size tap do you think would be best? and how far in do i go?

If you use the fitting which I suggested (above) you'll need a 1/8"BSP tap. A 1/8"BSP thread is 0.383" (9.7mm) in diameter and has 28 threads/inch. The fitting won't actually look like the generic picture on the Toolstation website - but will have a shoulder outboard of the thread. You'll need to drill and tap right through the wall of the radiator, and screw the fitting in so that the shoulder seals against a fibre washer.