Leeky diverter valve on a ‘telephone’ style bath/shower mixer tap

[jon hill 3Participant @jonhill3]

Not so familier with these style of ‘telephone’ shower / bath taps. I bought a used gold plated Samuel Heath set which leeked from every possible point.
I have rectified all but one leek which comes form the divertor handle through the stem. The orings have been replaced and more or less hold in the shower and bath function.
I have tried ptfe tape around the outside between the flange nut, connecting stem and handle which hasnt stopped the leek. I have also tried wrapping ptfe tape on the other side of the flange nut and handle, this has had some success but not elliminated the problem.

Can anyone recommend another solution eg soft jointing compound that is friendly to orings? I have though about jetblue but have heard it doesnt work well with rubber although perhaps small traces wont harm the rubber.

I also considered plumbers mate but this doesn’t seem to hold as well when wet and from experience.

[noel shelleyParticipant @noelshelley55608]

There are many combinations of O ring size and section I would try a different size or section, the 2 common types are BS sizes or metric. Sealing compounds are not really for Orings. Good luck.  Noel.

[jon hill 3Participant @jonhill3]

Hi Noel

I think the orings are just for friction so the divertor value holds in the shower or bath mode. Below the orings is grooved cylinder just like a honey scoop.

My best guess is the water is getting behind the grooved cylinder where it joins the spindle. Then travelling up the spindle of the flanged nut.

See sketch, water entering into arrowed gap.

I have tried putting ptfe in this gap which has reduced the water dribbling out but not completely.

Hence my though of using some sort of soft jointing compound like jetblue…..

[David JuppParticipant @davidjupp51506]

Samuel Heath web site claims they stock spares even for discontinued products – might be worth contacting their technical team.

[noel shelleyParticipant @noelshelley55608]

A picture may be worth a thousand words BUT the 2 Orings look a little small on OD and may not be sealing on the outer casing or the seating for the Orings is not smooth. Measure the section of the Oring and the OD and get new ones or try a alternative section,eg swap imperial BS for slightly larger metric. Is it all brass or is some of it die cast ali/mazac ? A flexible sealer is unlikely to work on moving parts. Noel.

[Dave HalfordParticipant @davehalford22513]

It’s possible the tap is intended for open vent hot water and the pressures are too high. but there should be a seal on the shaft and the lever should be removable from the threaded section.

Otherwise it may just be too worn to work properly.

[BazParticipant @baz89810]

Why not ask this question on a diy or plumbing forum or phone the local plumber.

[Grindstone CowboyParticipant @grindstonecowboy]

Might be getting this all backwards as usual, but as I see it, the issue isn’t with the o-rings on the white nylon part, is it? That is moved by the eccentric on the lever, so the leak is coming from where the handle goes through to that eccentric. So, the question is, can that “honey-scoop” part be separated from the external handle so that the seal on the shaft can be seen, and replaced? Isn’t graphited string the usual stuff used in that position on taps and valves? Is there some sort of gland nut that might be able to be tightened?

Rob

Edit – as Dave said above

[jon hill 3Participant @jonhill3]

Hi Baz, I am the local plumber / handyman, this is the first time and possibly the last that I install and service one of these style of taps. 😉

One diy forum suggested buying a new chinese nasty for £100 from screwfix.  I didnt reply to that. A new set if you can find one online would be around £1000 so must be worth fixing.

I couldn’t find a way of detaching the handle from the flanged nut perhaps its some sort of pressed fit?  I might try getting the grips on the honey scoop section to see if it unscrews.

Rob the white nylon part called the shuttle is only for the shower and bath selection which works reasonably well.

I did send a message to the tech guy at Sam Heath so we will see what he says.

[MacolmParticipant @macolm]

O rings work best with a small amount of compression only, and accurate and well finished surfaces.

One thing to avoid is two O rings in series – if the annular gap fills up with water, the self actuating sealing is spoiled. If everything else is correct, try removing one.

[jon hill 3]

On jon hill 3 Said:

 

See sketch, water entering into arrowed gap.

I have tried putting ptfe in this gap which has reduced the water dribbling out but not completely.

I’m not certain from what you say but I’m assuming the arrow is pointing to where the leak is. Have you tried a fibre or rubber washer at this point? And how much torque are you able to apply to the thin hex when tightening things down?

[noel shelleyParticipant @noelshelley55608]

If the water is getting to the gap then the Orings are not working. The eccentric is solid and seals via the Orings, if water is leaking down the shaft of the handle/hex nut then the Orings need attention. For the figures being mentioned, get 2 boxes of assorted O rings, one BS and the other metric, you will have a lifetime supply from 6mm to about 40mm. Good luck.  Noel.

[jon hill 3Participant @jonhill3]

Thanks Noel and everyone else for the input, plumbers aren’t generally engineers so an engineers eye on the problem can be very useful on an unknown such as this.

One other question do you know any suppliers of boxed orings other than plumbers merchants (already tried) suitable for hot water use? I do have a red box of orings, which Im not sure if they are metric or imperial.

Bill, as far as I know water is entering into the arrowed section and noticably coming out from the bottom of the handle.  There is no obvious way to disassemble this part from the flange nut, for example to replace hidden stem washers or reduce any play in the mechanism.

[David JuppParticipant @davidjupp51506]

The O ring grooves, and the bore of the housing where the O rings contact, must be clean.   If there has been leakage, there may well be some limescale present which could prevent a good seal.

Also clean the screw threads to make sure they don’t try to align the parts when assembling.  A little silicone grease on the O rings should help avoid pinching during re-assembly.

O rings don’t make wonderful rotary seals, they will need to be changed from time to time.

[MacolmParticipant @macolm]

In my experience, with two O rings in series, water (or oil) does often get into the gap, presumably because under some circumstances the pressure facing O ring moves back and forward and also rolls slightly. As an example, I have a pair of basin taps each with two O rings where the gap slowly fills with water. The tap has different diameters of O rings, so soon becomes water locked and unable to be turned off. With one O ring removed the problem has been gone for many years.

[jon hill 3Participant @jonhill3]

If it is the orings causing a slight weep, that might explain why the handle stem and cam are not clearly adjustable.  I did try fitting alternative orings which were a devil of a job to obtain let a alone measure up and guestimate the correct ones.

Definitely one of those jobs I wished I had never took on! 😉

If anyone can recommend a kit box of imperial and possibly metric orings that might fit the bill?  I think its the epdm type for drinkable water and hotwater use unless anyone knows different….

 

[noel shelleyParticipant @noelshelley55608]

A supplier of hydraulic gear may be able to help, or a seal supplier. If the number for the Oring is 0, 1, 2 and 2 other digits it will be the BS number, metric goes by the section diameter and id or od.

Try a branch of Hayley/Dexis.Or the bay, look for a set of about 400 in a plastic box and cost about £20   Noel

[jon hill 3Participant @jonhill3]

Is there much difference between epdm and nitrile orings for plumbing use?

[noel shelleyParticipant @noelshelley55608]

Ordinary ORings are nitrile and I would suspect that what was used though there are other exotic materials, viton,epdm,slicone Etc . Noel.

[duncan webster 1Participant @duncanwebster1]

Epdm orings are available from Simply Bearings. In theory they are better than nitrile in water conditions, but I doubt you’d live long enough to see the difference.

[jon hill 3Participant @jonhill3]

Yep epdm are quite often 3x the price but are they worth the extra spend?

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