Leaking waste pipes under kitchen sink

[daves61]

Hi - Novice here. Under our kitchen sink, the waste pipes are grey, with a green moving 'lip' and then a cover peice that in theory tightens over the connection. The two downward pipes from the sinks go into a cross pipe (along with the washing machine outflow) which then leads outside. However, if any volume of water goes down from the sink, it backs up to the joins and leaks out. I just can't get the downward pipes to commect into the corss pipe tight enough. How are these stupid pipes meant to work? Where can I get replacement pipes that slot together easily (without welding) - I've looked at Screwfix etc but they don't see to have many variations of pipe. Thanks for any advice.

 

[MrmarkG]

Has this always happened?? Try cleaning the pipes ( use vinegar & bicarbonate soda ) or buy drain cleaner your choice . I believe vinegar & bi carb is same thing at fraction of cost though

 

[rpm]

Are you within the UK?

 

[king of pipes]

Swap em out for one of these kits you may need other fittings but in most cases it will work out . Kop

 

[Ric2013]

OP is from Kent.

Probably the green moving lip hasn't gone into the internal cone of the fitting properly. It might be possible to clean it up, refit it correctly and it'll work, or it may be damaged and won't seal now. Should be airtight so shouldn't leak even if the water backs up.

From the description it sounds like a sink waste trap assembly that you might have to buy as a unit even though there are several separate parts involved. Which may be why you can't find what you need from Screwfix.

 

[snowhead]

I'd guess the tapered rubber (ish) cone washer(s) is stuck in the bottom of the cross pipe.
It should be on the end of the pipe.

Trap Sealing Ring

www.toolstation.com

 

[daves61]

Thanks for the replies. I've found myself having to try and tighten the joints every few months and it has previously worked, but not working at the moment. Where would you get an assembly from? Are they a standard size? It just seems like the weight of the cross pipe pulls apart the joints from the downpipes when it gets a lot of water in it.

 

[Deleted member 120897]

Sounds like the ones that get supplied with a fitted kitchen, or ikea. As per @kop renew with McAlpine sink kit, or x2 P-traps and altered pipes.

A photo of existing is worth a lot to us.

 

[daves61]

It is one sink with a waste bit in the middle between that and the draining board. What kit would be good for that?

 

[Deleted member 120897]

It is one sink with a waste bit in the middle between that and the draining board. What kit would be good for that?

The same as in post #4.

 

[king of pipes]

Mc alpine SK2 is what you need £20 ish from any main plumbing wholesaler or Screwfix outlet . Kop

 

[daves61]

But that's a double bowl - our's is a 1.5 bowl. Presumably the washing machine can be connected to the spare nozzle?

 

[king of pipes]

Its the one bud yes your washing machine can fit on the nozzle or be blanked off ??

 

[daves61]

Thanks but the Mcalpine is for a double or 1.5 bowl. How do you adjust it - I don't want anything where I have to start cutting pipes.

 

[Deleted member 120897]

Thanks but the Mcalpine is for a double or 1.5 bowl. How do you adjust it - I don't want anything where I have to start cutting pipes.

Sometimes you have to cut the adjustable stem piece that comes in the kit, without having seen your setup (again photos usually helpful), you might be able to fit a SK1a kit which is for bowl and half. McAlpine SK/1/A & SSK2 Trap Kit Bowl & 1/2 SK/1/A - https://www.toolstation.com/mcalpine-sk1a-ssk2-trap-kit/p89891?store=LC&utm_source=googleshopping&utm_medium=feed&utm_campaign=googleshoppingfeed&mkwid=s_dc&pcrid=515847200312&pkw=&pmt=&gclid=Cj0KCQjw4eaJBhDMARIsANhrQACzWTnlcZd_zyG09xr7VEYxnGdZ6k6bg6dWjXniHoFuFVFh6LKgdQAaAnezEALw_wcB&gclsrc=aw.ds

 

[king of pipes]

Piece a cake Dave just follow the instructions mate you're gonna have to shorten maybe 2 bits ya Mrs could do it it's that easy .

 

[Ric2013]

Or, at this point, call a plumber. It is, after all, what they are for.