Basin Waste and Piping and Not Aligned - Causing Weeping of Connectors

[Clemenza]

In my last posting, I requested assistance in exchanging a waste that had been fitted using silicone, without actually removing the basin. Mission accomplished. However, I now have a further issue for which I would welcome any suggestions or advice.

I decided to replace the McAlpine Pedestal Trap 1 1/4" Anti-Syphon trap. However, despite various micro adjustments of the top Spigot nut and the bottom universal connector, I am not confident of the water tight integrity of the fitting. I fear this is due to the lack of alinement between the bottom of the waste and the connector to which the pedestal trap is fixed. Although the trap fits to gap perfectly, it is not seated correctly, despite whatever steps I take in an attempt to remedy the issue.

My idea was to cut the pipe above the bottom elbow and use an appropriate flexible connector, which hopefully would allow water tight connections to be accomplished at both ends. by implication, the alignment issues will hopefully be rectified. Advice as to whether this idea would work in practice and suggestions as the the specific component I should use.

I attach an image of the pipe and another to illustrate how much space I have available

All suggestions gratefully received.

 

[Ben-gee]

Probably not necessary.
Where is it leaking from now?

 

[Clemenza]

Probably not necessary.
Where is it leaking from now?Below the Spigot nut, where it connects to the waste

 

[Clemenza]

I have managed to make both ends watertight, but typically not at the same time, hence my theory that the waste and pipe are not aligned. it could also be the the faces of the components are not fully seated.

Specifically, leaking has occurred below the nut that connects the top of the trap to the bottom of the waste. Similarly, leaking has occurred at the universal connector at the bottom of the trap.

Currently, the leakage is small and intermittent, hence my lack of confidence longer term and thus search for a more permanent remedy.

 

[Ben-gee]

How much pipe inserts into the compression joint at the bottom of the trap?

 

[Clemenza]

How much pipe inserts into the compression joint at the bottom of thAs

How much pipe inserts into the compression joint at the bottom of the trap?

The pipe is fully inserted into the recess. The trap really is a perfect fit.

 

[Ben-gee]

A compression waste joint allows for a considerable misalignment and as this is a replacement I think it should be possible to make it watertight both ends simultaneously- as presumably the previous one was?
Make the spigot joint first, with the compression joint not tightened at all- just with the nut, slip ring and cone washer on the pipe but below the trap.
Then slide the cone washer up the pipe to level with the bottom of the trap. Now slide the nut up, using it to push the slip ring and cone washer into place and tighten the nut hand tight but don’t graunch it up. This allows the pipe to be slightly misaligned if that is how it needs to be.
Honestly this will make if work, presuming you have the cone washer the correct way around .

 

[Clemenza]

A compression waste joint allows for a considerable misalignment and as this is a replacement I think it should be possible to make it watertight both ends simultaneously- as presumably the previous one was?
Make the spigot joint first, with the compression joint not tightened at all- just with the nut, slip ring and cone washer on the pipe but below the trap.
Then slide the cone washer up the pipe to level with the bottom of the trap. Now slide the nut up, using it to push the slip ring and cone washer into place and tighten the nut hand tight but don’t graunch it up. This allows the pipe to be slightly misaligned if that is how it needs to be.
Honestly this will make if work, presuming you have the cone washer the correct way around .

To be honest, this is virtually the same process I adopted when I fitted the trap initially (and since) I did assume that it was imperative to achieve a good seal between the waste and spigot recess top of the trap, so focussed on that first. I then ensured that the rubber cone washer was in place before slowly tightening the compression nut at the bottom of the trap.

Whilst the compression joint is now watertight, the spigot connection area is weeping intermittently. The waste I have fitted is a Bristan round push button style and appears to making a good connection, but something is clearly not right. Also, I am as certain as I can be that water is not leaking from above, having used Plumbers Mate, a poly basin washer and the brass back nut in fitting the waste itself.

I have not resorted to using PTFE tape around the bottom of the waste, nor indeed smeared any plumbers mate on the threads of the spigot nut. Its really frustrating.

 

[snowhead]

Is there a rubber washer on the top of the trap where it fits to the chrome waste?
Is the bottom face of the waste flat and not corroded and if it's plastic not split?
Is the leak from the trap to waste connection from below the spigot nut or above, if above it can sometimes be the chrome waste (if it's not new) has corroded within the thinnest part of the thread and is leaking down and over the nut?

If after a couple of attempts the trap to waste still leaks, get some PTFE, roll it up like string and wrap a few turns just above the top edge of the washer, it'll push up into the bottom of the waste and provide a larger sealing surface.
In the past where the bottom of the chrome waste has corroded I've removed the washer and wrapped many turns of ptfe to create a large soft seal.

As BEN has said, the lower compression joint will normally seal with quite a noticeable misalignment.

 

[oz-plumber]

Something is very wrong if you can't make that water tight.
That's not misalignment by any figment of imagination.

Get some new rubber seals. Make sure they are the correct ones

 

[Ben-gee]

We are now into the realms of skill/experience - you will learn from this and ultimately get a feeling of satisfaction, also perhaps an appreciation of the value of a good tradesman.

 

[Ben-gee]

In my experience the most likely source of this leak will be between the ceramic and the metal waste fitting itself.
The space between the threaded body of the waste and the ceramic “tube” it goes through must be sealed at the bottom. Assuming it is a slotted waste, this area will fill with water and you need to ensure it can’t seep out at the bottom. The rubber washer supplied is often inadequate for this purpose so most people seal the space using silicone or plumbers mait (putty). I prefer plumbers mait because i) it can be tested immediately and ii) it smells and feels as though you’re a proper old skool plumber!

 

[Clemenza]

Is there a rubber washer on the top of the trap where it fits to the chrome waste?
Is the bottom face of the waste flat and not corroded and if it's plastic not split?
Is the leak from the trap to waste connection from below the spigot nut or above, if above it can sometimes be the chrome waste (if it's not new) has corroded within the thinnest part of the thread and is leaking down and over the nut?

If after a couple of attempts the trap to waste still leaks, get some PTFE, roll it up like string and wrap a few turns just above the top edge of the washer, it'll push up into the bottom of the waste and provide a larger sealing surface.
In the past where the bottom of the chrome waste has corroded I've removed the washer and wrapped many turns of ptfe to create a large soft seal.

As BEN has said, the lower compression joint will normally seal with quite a noticeable misalignment.

Both the trap and waste are brand new and of good quality. No corrosion. I think I will try the layering of PTFE tape on the top of the spigot washer. I can access this area without removing the bottom compression fitting with watertight currently.

 

[Clemenza]

Both the trap and waste are brand new and of good quality. No corrosion. I think I will try the layering of PTFE tape on the top of the spigot washer. I can access this area without removing the bottom compression fitting with watertight currently.

Something is very wrong if you can't make that water tight.
That's not misalignment by any figment of imagination.

Get some new rubber seals. Make sure they are the correct ones

I used the PTFE layering technique snowhead suggested earlier today on the spigot joint. This sorted the problem instantly.

However, despite the leak on the compression joint being virtually sorted, I still detect very small isolated speckles of water, that show up on the blue tissue paper I use to test the area. Is there any equivalent techniques to bolster the watertight integrity of the compression joint.

 

[Ben-gee]

Just make the joint as I told you earlier. Do the nut up by hand , it should run freely and then resistance is felt- at that point give it say 1/4 turn more.
Test and if leaks then nip 1/16 turn and repeat.
The trick is do not over tighten.
This is what I’d was referring to as skill and experience- we just get it right first time by feel. But the above method will work if followed.

 

[Clemenza]

Just make the joint as I told you earlier. Do the nut up by hand , it should run freely and then resistance is felt- at that point give it say 1/4 turn more.
Test and if leaks then nip 1/16 turn and repeat.
The trick is do not over tighten.
This is what I’d was referring to as skill and experience- we just get it right first time by feel. But the above method will work if followed.

Ben-gee

All is fine now. Thanks for your kind advice, without which I would not have sorted the problem.