Should I give Plumber's Mait time to dry before refilling cistern?

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A couple of months ago I replaced the flush unit in a close-coupled toilet, and I resealed using a new doughnut and a ring of Plumber's Mait on both sides of the (new) metal coupling plate. I let the cistern refill as soon as everything was reinstalled.

Everything seemed fine, but I've now got a regular drip from just one of the two bolts that hold the cistern to the bowl.

When I reseal it, should I leave the Plumber's Mait to dry before refilling the cistern?

And should I tighten the plastic backnut as much as I possibly can, or should I just snug it up? I'm wondering if I possibly tightened it to the point that the Plumber's Mait on the side of the bolt that's now dripping got squeezed too thinly to let it seal properly.

drip.jpg
 
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I’m not entirely sure that plumber’s mait does dry. However that bolt appears cockeyed, so if it is, this would be the 1st place I’d be looking at.
 
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A couple of months ago I replaced the flush unit in a close-coupled toilet, and I resealed using a new doughnut and a ring of Plumber's Mait on both sides of the (new) metal coupling plate. I let the cistern refill as soon as everything was reinstalled.

Everything seemed fine, but I've now got a regular drip from just one of the two bolts that hold the cistern to the bowl.

When I reseal it, should I leave the Plumber's Mait to dry before refilling the cistern?

And should I tighten the plastic backnut as much as I possibly can, or should I just snug it up? I'm wondering if I possibly tightened it to the point that the Plumber's Mait on the side of the bolt that's now dripping got squeezed too thinly to let it seal properly.

View attachment 235250
Plumbers mait doesn’t dry :)
How come you used plumbers mait in the way you have?
Everything on a toilet doesn’t need to be tightened to within an inch of its life.
It’s the doughnut washer that is creating the seal.
 
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How come you used plumbers mait in the way you have?

After changing the flush, I reinstalled it without any PM. It immediately started leaking. I had a bit of a Google round and found various videos from plumbers demonstrating how to use PM, so I tried it and it worked (or at least seemed to).

This was the video that convinced me:


Everything on a toilet doesn’t need to be tightened to within an inch of its life
Cool, when I put it back together again I won't feel the need to tighten the backnut so much.
 
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Pretty sure I've got a tub of that somewhere :confused: 16 years in the trade and I've never found a good use for it.
 
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I used silicone on ours, hasn't leaked since.

Liberal coating and snug up the nuts.
 
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I used silicone on ours, hasn't leaked since.

Liberal coating and snug up the nuts.
That could be a pain if or when it needs taking apart again.

Shouldn't need anything other than the siphon seal (inside the cistern) and the donut.
 
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Get rid of the plumbers mait and fit a new doughnut, make the siphon in with mastic, refit it and you should be ok
 
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make the siphon in with mastic
You mean use some kind of sealant to fill between the siphon outlet and the hole in the cistern? Will any old bathroom sealant do?

"Mastic" seems to be one of those generic words that can mean a huge variety of products.
 
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I have used dow 785 to good effect.

Blup
 
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That could be a pain if or when it needs taking apart again.

Shouldn't need anything other than the siphon seal (inside the cistern) and the donut.

That was 2nd time round, it leaked originally..
 
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If the nuts and bolts aren't sitting straight in the hole then the cistern isn't fitted square to the pan. Over time the doughnut and cistern has settled and the doughnut is now out of alignment and starting to leak. The cistern needs lifted, new doughnut added and then sit the cistern down square onto the pan platform and then tighten the wingnuts down equally either side.

Hopefully the pan is sitting the correct distance from the wall otherwise it will never sit squarely to the wall and the pan and you will always have issues.
 

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