Emergency help please - got a leak

[dilalio]

Thanks - I seem to remember you helping me with the old one, years ago no matter what you suggested, I tried it (Plumber's Mait etc), but it still wouldn't seal, so I used silicon. So I'm interested to read on the Victorian Plumbing web link you sent me "When installing we recommend running a thin bead of silicone sealant around the recess of the sink waste hole"!

Maybe it wasn't just me after all

I don't like using silicone as you can't test it till its cured.
Also a swine to remove when replacing with new.
But it's a plumber thing.... Some prefer the other.

 

[Madrab]

Aye trouble is, people like me don't know that (I do now ) - I imagine those pipes have been like that since the house was built in 1994, so you kind of assume things are all OK

Of course, certainly wasn't suggesting it was your fault at all, more so pointing it out for others not in the know, to take a look around and hopefully avoid the unfortunate predicament you have found yourself in.

As far as sealing in the waste, absolutely no point is using anything inside the basin, the seal is only created at the point the nut and seal as it compresses the washer under the basin.

My leak free process is to - Insert the waste and centre in the hole. When you look under and up you will see a gap all the way around the shank of the waste, fill that gap with silicone all the way around. Not so much that it would fill the overflow slot but enough to fill up the gap all the way around and fill the threads. Holding the waste in place from inside the basin, offer up the washer and nut and hand tighten as far as possible then half a turn with a large pair or pliers. Any silicone that squeezes out, smooth with a finger and transfer the escess to the threads below the nut, all the way around, just as a belt and braces. wipe and excess away with some blue roll.

I always use silicone as I'm always cursing the last chap that used mait, as it always seems to get everywhere and just doesn't want to come off of anything

 

[dilalio]

Right... by "top one" do you mean the thin one that's on the top surface of the basin?

Yes... They're crap! Foam ones aren't so bad but the rubber type are useless and will squeeze out of position with the silicone.

 

[dilalio]

the seal is only created at the point the nut and seal as it compresses the washer under the basin

Not when bowl drains through this point into the slots and down the waste

 

[Madrab]

Not when bowl drains through this point into the slots and down the waste

Wouldn't matter, when a waste leaks it should only leak down the outside of the shank, if that is sealed by the washer and the nut (and a little silicone) below then the water will always be directed into the main waste hole and into the trap (edit) as it can't get past the lower seal. Hence why basin mates work so well as they are jammed into the gap all the way around by their shape and it allows the seal to be forced into the threads and that gap.

I've found that coming across a waste that leaks, it's only when the plug is opened that it leaks, the water runs into the waste, out through the slots and down the outside of the waste shank and past the threads/nut under the basin. Usually the top seal is fitted and with the plug in that stops the water running past it down the outside of the waste and there is no leak.

 

[dilalio]

Wouldn't matter, when a waste leaks it should only leak down the outside of the shank, if that is sealed by the washer and the nut (and a little silicone) below then the water will always be directed into the main waste hole and into the trap (edit) as it can't get past the lower seal. Hence why basin mates work so well as they are jammed into the gap all the way around by their shape and it allows the seal to be forced into the threads and that gap.

I've found that coming across a waste that leaks, it's only when the plug is opened that it leaks, the water runs into the waste, out through the slots and down the outside of the waste shank and past the threads/nut under the basin. Usually the top seal is fitted and with the plug in that stops the water running past it down the outside of the waste and there is no leak.

No... I meant the bowl would drain when you don't want it to! You know... When soaking your socks over night

 

[Madrab]

No... I meant the bowl would drain when you don't want it to! You know... When soaking your socks over night

Oh right, apols ... yeah, for sure!

 

[Roger465]

Well, I ordered the item you suggested from Victorian - bit of a nightmare as their site wouldn't take my order no matter what I did, but a lovely lady sorted it out for me by phone.

I plan to encapsulate the unit in silicon, shove it into the hole, then hit it with a hammer

Living here in N Ireland, I'm cautiously optimistic it'll be here by early 2026

 

[Roger465]

So... I found Plumber's Mait difficult to use last time, as far as I can remember (not very far at my age, sadly), but I still have the tub. Consistency seemed a bit stiff, so it was hard to spread I think...?

Anyway, when putting it (eg) between the top of the waste unit and the basin, do you leave the supplied washer out altogether, or use both?

Same underneath - would you put some both sides of the rubber washer, or just one?

Thanks

 

[Madrab]

I don't use anything inside the bowl, just the sealing washer that comes with it, never had an issue. I Only use a sealer underneath @ the nut/washer.

 

[dilalio]

So... I found Plumber's Mait difficult to use last time, as far as I can remember (not very far at my age, sadly), but I still have the tub. Consistency seemed a bit stiff, so it was hard to spread I think...?

Anyway, when putting it (eg) between the top of the waste unit and the basin, do you leave the supplied washer out altogether, or use both?

Same underneath - would you put some both sides of the rubber washer, or just one?

Thanks

I take a squashball sized lump out the tub. Roll it between palms as if you were rolling dough balls. Do this until the ball warms up and becomes pliable.
Then roll it out to make a 10mm sausage.
Wrap this around the upturned waste neck, so that it goes around the flared part but doesn't cover the slots for the overflow.
Use your finger to gently push the sausage against the radius of the flared end. No washer!
Turn waste upright and place into basin hole, make sure you align slots with overflow channel, moulded into basin.
Push down evenly and firmly so that mait starts to squeeze out around flared end.
Make another sausage and, from underneath basin, wrap this around neck of waste, up against basin throat, covering the anular gap.
Again gently push sausage into place so that it haunches between basin and waste.
Slip bottom washer up neck of waste, against putty.
Spin on the back nut and tighten as much as you can by hand, whilst holding a screwdriver wedged into slot in waste and against moulded channel to prevent waste turning and blocking slots from channel.
Tighten a bit more with basin wrench/grips.
Putty continues to ooze out.
Tighten but not over tight!
It's a learned thing.

Use fingers to remove excess from below and a small flat bladed screwdriver/screw/nail to remove excess from around the flared end, in the basin.
Roll the bits into one ball and place back in the pot for next time.

Did 6 of these replacements, in one house, last week. Took me longer to remove residue silicone which was pumped in everywhere, than it did to fit with plumbers mait.

All tested and leak free at first attempt.

 

[Roger465]

Thanks both

We'll see how it goes when the new waste unit arrives... e-ven-tually, as Manuel put it in Fawlty Towers....

 

[Roger465]

What do you call that wrench thing with the right-angled end which is used to tighten the big nut round the waste from the bottom?

I've only got those kind of pliers with adjustable jaws, and it's very awkward to get at, so they're chewing the hexagon faces of the nut

 

[Harry Bloomfield]

But the trouble is, this one has started leaking - ie, when you push the plunger down, it clicks and seems to locate OK, but the water drains slowly out (down the drain this time, not between the drain and sink).

The mechanism which pops the plug up, is usually adjustable - perhaps that is resting too high, preventing the plug sealing.

 

[dilalio]

What do you call that wrench thing with the right-angled end which is used to tighten the big nut round the waste from the bottom?

I've only got those kind of pliers with adjustable jaws, and it's very awkward to get at, so they're chewing the hexagon faces of the nut

You shouldn't need to go THAT tight... It's not under any real pressure!

I use these and just get it in there however I have to!

Silverline Wide Jaw Plumbing Pliers Length 250mm - Jaw 85mm (633562)
£6.75
Amazon.co.uk
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