Leaking 110mm Soil pipe socket seal

30 Aug 2022
Reaction score
United Kingdom
Hi all,
Got an old 60s/70s PVC soil stack, the pipe socket (which is partly painted pink in the photo) is Hunter branded and has an old O-ring design quite different to modern stuff.

I tried to revive the o-ring with some grease and ran a short length of new grey PVC pipe into it, then have a new McAlpine WC flexi connector running into that. Flushed a few buckets down last night, no drips, cracked open a beer (jinxed it!)

This morning I noticed there was a tiny bit of water which had weeped out of the bottom of the socket joint (between the new grey pipe and old pink painted socket) :( Tried again and it takes about 30 mins to appear, maybe a bit of standing water in the pipe seeping backwards through the o-ring.

Would rather not replace the stack, got another bathroom connected upstairs.
Would some CT1/OB1 work? I know it might be considered a bodge, would like it to last a good few years.

Or could I remove the snap cap and old O-ring and solvent weld in a new section of pipe? The grey plastic inside the socket is discoloured at the bottom and would need something abrasive to get it back to grey colour again. I've read that you can't do this though as pushfit sockets are too large to solvent weld. (https://www.jdpipes.co.uk/knowledge...ext=The only thing you can,a seal on the pipe.)

Any ideas greatly appreciated Been messing about on this project for way too long and have got to the point where I need to tile round the soil pipe..


Sponsored Links
JDP are being rather ambitious with their statement "This is a forgiving style of jointing that can be pulled apart and reconnected as many times as needed when installing a soil system, making replacing damaged or worn out sections relatively quick and easy.", unless the system has worn out within weeks of first installation, I'd never attempt to try and redo a Ring Seal joint, the seals harden over time and as you've found, will leak if disturbed....

Options are I think, try and make it seal with Silicone, Denso tape or suchlike, remove snap ring and seal, see if a Flexseal connector will sort it, or cut the junction out the stack, and graft a new junction back in. The latter though will depend on available room, and looking at the waste pipe, I suspect that joins via a Boss slightly lower down, making available room even less.
Thanks @Hugh Jaleak yeah there is a boss pipe directly beneath it which I had fun and games connecting to.

Do you mean this type of flexseal coupling? Try and get one end over the socket?

Yup, agree, use a wet grab/stick like sh*t silicone adhesive - very like (edit) OB1 but more suited to the job of sealing up joints like that, being a silicone polymer adhesive. It will even grab when wet but try to avoid that.

Mark grey piece in socket, grey piece out, dry internals/seal and soil pipe, gloves on, a nice ring of wet grab all the way around just before where the insertion ark is and then insert and twist, adhesive should bunch up around the branch lip, use a finger/scraper/knife to smooth adhesive all the way around and leave dry overnight if poss. It will set like a hard rubber and is pretty well permanent.
Last edited:
Sponsored Links
@Madrab didn't think about marking the grey pipe and applying the adhesive like that, was just going to try and force it in once it was all connected. Top tip, cheers !

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local