Kitchen mixer tap - how is it fixed?

[Larches]

We are replacing our kitchen mixer tap, but I haven't figured out how to remove the old one yet as I'm a lowly DIY-er and unfamiliar with the fitting that holds it in place.

The old tap is a Franke Zurich, and inspecting underneath the sink I can see it has what looks like a brass tube with a hexagonal end with a notch in it, projecting from the base of the tap just in front of the two water feed pipes. Picture attached. So my questions are: what is this called, and is there a particular tool for (un)fastening it?

Having just managed to get a second picture from directly underneath (quite possibly the most pointful use of a 'selfie' camera ), I can see that there is a screw part-way up the brass tube so it looks like some kind of sheath. Just had a quick go with a slim screwdriver but it won't budge (not helped that it's at the back of the cupboard so access is difficult, as ever).

I'm about to pick up the replacement tap which has flexi tails instead of copper pipe so I may have further questions on fitting very soon! Meanwhile though, if anyone can enlighten me on the existing fittings then I would be grateful.

T.I.A.

 

[exedon2]

Have a look on line for mono block tap spanner normally sold in set's of 3 probably need them to fit new tap.

 

[Ric2013]

The solid tails are soft copper, so just carefully bend them aside slightly and use a spanner on the nut or a socket from a car socket set. You're replacing the tap anyway so no need to be be too precious about the existing tails (and even if they break and you want to re-use or sell the tap, you should be able to get replacements).

 

[Larches]

Thanks both. @Ric2013 that's a fair point about the existing tails, I was a bit worried about forcing them out of the way as there's not much give, but as you say they'll be replaced anyway. It's just that this retaining bolt (or whatever it's called) is not a type I had come across before, and I wasn't sure whether I was supposed to be trying to undo the brass bit itself or the screw inside it.

Looking at the new flexi tails, they are quite long, so presumably no reason not to do away with the section of pipe with the push-fit connectors, so I can just screw the tails directly onto the isolation valves?

I guess I may need to check if the valves have a flat top though, and buy some tap tail adaptors if not (don't really want to risk damaging the rubber washers and getting a leak at some point).

 

[ShaunCorbs]

No you can’t as you need male irons eg JG Speedfit Brass Push-Fit Adapting Male Cylinder Coupler 15mm x ½ - https://www.NoLinkingToThis/p/jg-speedfit-brass-push-fit-adapting-male-cylinder-coupler-15mm-x/23662

 

[Larches]

No you can’t as you need male irons eg JG Speedfit Brass Push-Fit Adapting Male Cylinder Coupler 15mm x ½ - https://www.NoLinkingToThis/p/jg-speedfit-brass-push-fit-adapting-male-cylinder-coupler-15mm-x/23662

I might be talking rubbish, but just looking at the valves, I thought it already was male at the top end, with a compression nut on the pipe above screwing down onto the valve - so with that top nut removed, would a flexi tap tail with female connector (as shown in last picture) not just screw onto it in the same way?

Although come to think of it, I guess that means I couldn't use a tap tail adaptor if there's no nut on the valve itself to hold the adaptor.

 

[ShaunCorbs]

It would but it would cut into the rubber as it’s designed for an olive eg sharp edge /. Ridge

 

[Larches]

It would but it would cut into the rubber as it’s designed for an olive eg sharp edge /. Ridge

Ah right, yes, that's what I was getting at before regarding the adaptors, although I was obviously tired last night as I think my last comment made no sense!

So it seems the best solution might be to get a pair of flat-faced tap tail adaptors for a few quid and fit those where the copper currently comes into the top of the iso valves, then fit the flexi tails onto those to avoid damage to the rubber.

 

[ShaunCorbs]

Yes you can or use the ones I linked where the couplings are now

 

[Larches]

Makes sense, thanks for your help.

 

[Larches]

Well, the replacement is done and it didn't go too badly - i.e. new tap works fine, looks good, no major injuries and the house isn't flooded.

So that's the good bit out of the way. Unfortunately, there is just a very slight bit of intermittent weeping from somewhere on both hot and cold sides.

I say 'somewhere' because the water is just around the brass adaptors and there is such a small gap between the compression nut and the tap tail fitting that it's hard to tell whether it's oozing up from the valve or down from the tap.

Having said that, I've tightened up the compression nuts as far as they'll go without applying what would seem like excessive force, but the tap tails are a different matter. I had tightened them to a point that felt reasonable, but then I spotted the leak and found I could tighten them a bit more. A short while later - same process occurred. And again. So now I'm wondering how far I can/should go with tightening these as I don't want to risk knackering/distorting the rubber seals (if I haven't already). Is it normal for these to resist but then allow more tightening when they've been left for a bit, and how do you judge how tight is too tight?

Incidentally, I've got PTFE tape (2 layers) around the threads on both connections, not sure if that is helping or hindering!

Any tips for resolving this would be welcome.

 

[ShaunCorbs]

Don’t need the ptfe and should be from hand tight around 1/2-3/4 of a turn on the nuts

 

[Larches]

Thanks, I'll give that a try and see how it goes.