Bath drain gasket only leaks when bath overflowing, not when draining

[MikeDelta52]

Hi

I'm really stumped, I thought I had a logical brain, but this is really confusing me, please help me choose the right next steps.

My bath drain leaks when water goes down the overflow. The leak looks to be between the grey rubber gasket which clips onto the fibreglass of the bath around the drain hole. What I don't understand is why I can fill the bath almost full, drain it via the plughole and have no leak, but have a significant (water dripping through the light fitting downstairs) water leak when the overflow is active. The overflow joins the main drain in the chamber directly beneath the bathplug, the bit which has the plug raiser assembly in it.

I want to be able to fix it, have taken it all apart, cleaned the fixings and tightened all the joins, including adding a little silicone to the plughole bits. The only bit I didn't mess with was the grey gasket because I don't have a replacement one of those and was unsure it would go back on if I removed it. I'm only an amateur enthusiast!

Is this something common? Do you think I should just replace the gasket? Should I get a plumber to replace the whole assembly? The overflow itself is in the middle of the bath against the wall, so a real pain to get to.

Please ask questions as required, I probably haven't described it very well.

Thanks for your help.
Mike

 

[CBW]

Sounds more like a failed seal/loose overflow as opposed to the bottom seal.

 

[MikeDelta52]

Sounds more like a failed seal/loose overflow as opposed to the bottom seal.

I thought the same, but am confused that the leak looks pretty convincingly like it's coming directly from the drain directly next to the underside of the bath. The pipe coming from the overflow is dry. I will try to work out how to take the cap off the overflow to see if it is obviously disconnected.

 

[terryplumb]

Show us a picture of the point of leakage . I think you are describing where the overflow pipe meets the waste fitting below the bath ,and there are several types. We need to know exactly what your set up is

 

[lostinthelight]

I thought the same, but am confused that the leak looks pretty convincingly like it's coming directly from the drain directly next to the underside of the bath. The pipe coming from the overflow is dry. I will try to work out how to take the cap off the overflow to see if it is obviously disconnected.

If the water is leaking from where Chris_W says it may not run outside the overflow pipe but down the end if the bath so feel for water with a tissue there
Edit : or side in your case