Leaky basin trap - advice needed!

[Yehia]

Hi all,
I've fitted a new bathroom suite this week.
All done, except for this:
I cannot get the trap under the basin to seal properly. When I hand- tighten the trap's upmost nut to the threaded metal waste outlet, there's still 'give' in the trap inlet, i.e. you can move / waggle it.
As a result, water seeps out of the join below this nut.
I have tried using a basin S-trap and now a P-trap; same result.
I think it's because it's one of those lever- assembly plug affairs, and the casement which sticks out from this gets in the way of the nut and won't allow it to tighten all the way up.
Does this situation sound familiar to anyone?
I'm not sure how to solve it.
My ideas so far:
1. Try to get as much silicon sealant as possible in under the nut to seal it up (not ideal, as a nudge would probably break the seal),
2. Cut a bit off the top of the plastic nut on the trap- but how much? 5 mm? 10 mm? Would it work anyway?
3. Insert a second black rubber washer on top of the one supplied inside the trap's upmost nut, and try tightening it again.
4. Insert another washer inside the nut, but under the raised plastic rim on the inner pipe (so as there's a washer both under and above it) before tightening.
What should I do, guys?
I'm at the end of my tether with this!
RSVP

 

[PlumbBobBob]

get a set of grips on the nut and tweek it up should only need 1/4 turn extra

 

[Puddle]

If above fails

Remove trap and cut about 5mm from top of plastic nut that attaches to sink waste,then refit and all should be ok,seems you have a short thread on your basin waste,this is not uncommon

imho

 

[Destroyer2813]

If its the nut from the trap on to the waste not sealing and its a pop up waste sometimes you do hqve to cut 10mm ish off the nut so tightens up fully

 

[Puddle]

Ok,meet half way,maybe 7.5 mm from nut

:tongue3:

 

[kirkgas]

Ok,meet half way,maybe 7.5 mm from nut

:tongue3:

or if you use an old hacksaw blade it will be 5mm at one side and 10mm at the other

 

[Destroyer2813]

Your fingers obviously work faster than mine puddle

 

[Phil]

Nothing worse than this problem, even when the nut doesn't catch you cant get your fingers/grips round enough to get decent purchase on the nut without draging the pedestal forward and grinding ceramic.

And those dreaded Bathstore pedestels with the two return peices that you can barely get two 15mm pipes into nevermind your hand. The designer needs to be hunted down like a dog and shot!

 

[Yehia]

Ho-Ho - I get the idea: cut the thread off the nut, someway between 5-10mm. A bit of hacksaw action for Xmas Eve it is then!
Cheers gents - I'll sleep better tonight now!

 

[Guest123]

I'd cut it 7mm and one eighths of an inch just to keep the parrot happy!

 

[jaybob]

also cheack u not crossed threading them as this is not uncommon and they nveer seal properly. i might be barking up wrong tree but just a thort 🙂

 

[WaterTight]

the existence of cross threading, much like standing bare-footed on an upturned three-pin plug, is unarguable proof of satan

 

[Resolute]

I'm normally very careful not to cross thread anything but I was rushing a job yesterday and crossthreaded the connection to a toilet fill valve - a lot of water pi$$ed out when I put the water back on and I may have uttered a few expletives!

 

[Yehia]

Def not cross threaded; even used a hand-held mirror to check behind pedestal during job! Good thought though - many thanks for feedback.
Think it's depth of seal, or lack thereof. Will try the hacksaw tactic. Will post result tomorrow.
Goodnight all.

 

[jaybob]

no worys dude. once you esemble it and get it right take back of and use a little silicone as recently every trap ive used decides to leak (landlords stock of b an q s@#t he had me using for the bathrooms ive being putting in on the newbuild there seals are wafer thin) 🙁

 

[PlumbBobBob]

b&q own make is rubbish get mcalpine it has a lip that goes inside the drain spigot and seals much better

 

[WHPES]

Make sure you haven't lost the black sealing washer behind the nut

 

[stevetheplumber]

i learnt my trade using copper traps which were to say the least difficult if they didnt sit exactly right they leaked and any thing that needed adapting ment getting out the brazing kit and the kingly tool . when we first went form copper to plastic traps it was a bit hit n miss regarding quality lots of leaks, threads that crossed easily we even had some traps that literally split in half due to poor design or choice of material
then the mcalpine range came out we all moan about shoddy stuff and never give praise where its due but in my experience mcalpine stuff is always capable of doing what it should and they seem to be in touch with whats needed by the guys on the ground with items like trap extenders and flexi connectors
so id like to say thank you mcalpine for making the last twenty years considerably easier
(kingley tool was used to expand the bead at the wastes fitting end of a trap)

 

[dontknowitall]

Loads of silicone with excess wiped away is the key.

Silicone round top of basin trap, then placed into basin.

Underneath:
Silicone on basin.
Push washer against basin
Silicone on flat part of nut.
Tighten.
Wipe away all excess.

 

[Guest123]

Gawd Steve, I fitted copper traps too and still remember it. Feeling old now and on Christmas Eve, ta very much! LOL

Praise be to Mr Mcalpine, lord of the traps.