Basic plumbing question...

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ChasB

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Hi folks! :)

I've just fitted a new sink, and got a leak!

20210827_183054.jpg

The top hose is from the tap.
The brass thing just below is a male/male sex changer that measures 204mm (0.8in) across the outside of the thread. The white stuff on the thread is plumber's tape
The plastic connector at bottom is the hose from the boat's plumbing. The hose has a 5/8" outer diameter.

The leak is from the bottom of the plastic connector. Maybe I overtightened it. :( I think I need to cut the plastic hose and replace the connector. I'm a novice to plumbing, but a keen learner. ;)

What bits do I need to go out and buy?

Many thanks! (y)
 
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I suspect the thread on the lower part of the brass connector is not long enough to seal against the rubber washer in the grey fitting so it doesnt matter how much you tighten it, it'll leak.

Can you confirm whether the grey fitting has a rubber washer in it?

You may get away with another washer but this is a bodge and a hose tail would be best as Aeolus says.
 
ChasB said:
Hi folks! :)

I've just fitted a new sink, and got a leak!

View attachment 121552

The top hose is from the tap.
The brass thing just below is a male/male sex changer that measures 204mm (0.8in) across the outside of the thread. The white stuff on the thread is plumber's tape
The plastic connector at bottom is the hose from the boat's plumbing. The hose has a 5/8" outer diameter.

The leak is from the bottom of the plastic connector. Maybe I overtightened it. :( I think I need to cut the plastic hose and replace the connector. I'm a novice to plumbing, but a keen learner. ;)

What bits do I need to go out and buy?

Many thanks! (y)
Click to expand...
I would recommend one of these Metric Compression Hosetail (13mm or 10mm to suit the bore of your grey hose) . Discard the nut that comes with it but keep the olive. Remove your brass thing and screw your silver nut on the top hose onto the new fitting I recommended using the olive that came with it but without any plumber's tape. Don't over tighten. Now cut that plastic fitting off your plastic hose and slip the hose over the hose tail on the new fitting together with a stainless hose clip, tighten just enough to seal but no more.

www.solocoastalsailing.co.uk
 
Thanks.

Maybe worth adding that the sink went in a while ago, and the water's only just been turned on.

The plastic hose is not rigid and is flexible to a degree, but only a bit. I'm not sure how pliable it would be under compression, so whether a hosetail would work. Would heating it help?

I think you may be right S-F, the thread may not be long enough. There was no washer in the fitting (did my helper at the time lose it? ) so I put in an approximation. But I think (?) the leak is from around the metal clip at the very bottom. Should have looked more closely. Always difficult to make these judgements when away from the boat.

I'll go down to Homebase and see what I can find...
 
By seeing the ptfe tape on the male thread I would assume when fitting you did not know it was to be sealed on the flat face with a rubber washer, it’s either not long enough to seal or needs a couple of fibre washers to fill out
 
Daverw said:
By seeing the ptfe tape on the male thread I would assume when fitting you did not know it was to be sealed on the flat face with a rubber washer, it’s either not long enough to seal or needs a couple of fibre washers to fill out
Click to expand...
Or the PTFE which shouldn't be there is actually preventing the cap being screwed on far enough to seal against the internal gasket which may or may not be there...
 
I love PTFE tape! I once drilled through a wall and accidententally shaved the edge of a central heating pipe causing a small leak. I wrapped some PTFE tape around it as a temp repair. It worked. 29 years later it's still there!

Maybe time I went back to that... :LOL:

I bought the drain-off below, which has the advantage of having an on/off tap built in . I cut the plastic pipe and found it to be a little small, so I put it in hot water, slapped some sika on the drain-off, pushed it on, and added a jubilee clip. I put some PTFE and a little sika on the thread and Bob became my uncle!

So nice not to have leaky plumbing.

Thanks for all the advice! ;)

Screen Shot 2021-08-30 at 10.03.30.jpg
 
What exactly is the brass fitting, there are many that look similar but are NOT.

My guess is you have a15mm pipe coupler with the olives and nuts discarded. These have a cone shaped entry for the olive and do not present enough of a flat face for the washer to seal against. If it did, the top one would not be wrapped in half a roll of ptfe tape,

Get the correct fitting or similarly bodge the bottom connection with a load of ptfe tape.
 
ChasB said:
I love PTFE tape! I once drilled through a wall and accidententally shaved the edge of a central heating pipe causing a small leak. I wrapped some PTFE tape around it as a temp repair. It worked. 29 years later it's still there!

Maybe time I went back to that... :LOL:

I bought the drain-off below, which has the advantage of having an on/off tap built in . I cut the plastic pipe and found it to be a little small, so I put it in hot water, slapped some sika on the drain-off, pushed it on, and added a jubilee clip. I put some PTFE and a little sika on the thread and Bob became my uncle!

So nice not to have leaky plumbing.

Thanks for all the advice! ;)

View attachment 121610
Click to expand...
I don't think that the "o" ring spindle seal in that type A drain cock will hold back the water for long. I was never intended to be used as you have, its a butcher's bodge at best.
 
Check the size of the incoming pipe: it looks like it’s 10mm. Cut it off square and fit the appropriate Speedfit adaptor: a wide selection is available here 10mm, 15mm, 22mm & 28mm Plumbing Fittings Sizes | Speedfit. Speedfit are a simple push to fit solution and easy to use. When connecting the tap tail, don’t overtighten, finger tight only. It’s what I have fitted throughout the boat (and campervan).
 
I suspect that the pipe fitting the OP has used to solve his problem will last longer than his ownership of the boat. My kind of solution!
 
Don't wanna put a dampener on your repair, but........the fitting you used is a 1/2 inch drain off. This is not designed to hold positive pressure on its outlet. What sometimes happens is when draining through said valve and you place thumb over outlet ( to swap bucket usually). The water flow diverts through the small o_ ring type stuffing gland exiting around the squared off section, and soaks your protective work sheets. Generally only occurs on older drain offs so you possibly be ok.and soaks re 12 water pump starts to kick in randomly you'll know where to first look ..
 
mmm you say leak is at BOTTOM of plastic connector .. but picture shows the whole junction wet from the chrome flexi nut down.

Just confused why use 2 intermediate connectors ? The plastic pipe appears to have a compression clip - so I would be inclined to unclip .. remove the plastic and brass connectors ..

Insert a male metal connector into plastic pipe - fasten compression clip to seal - then put decent washer in the chrome flexi pipe nut and screw it up.
You can of course use PTFE tape as well ...
 
Those chrome flex fittings have a sealing washer built in. BUT, the entering thread needs to have a quite narrow sealing width (i.e. a large internal diameter) so that it beds onto the washer. The use of PTFE tape on that sort of joint allways raises flags.
 
Well, as i said, i've done it now. and it seems to work OK.

"not designed to hold positive pressure on its outlet" But this is not mains water pressure. Just whatever the pump is providing, Which I'm assuming is a lot less. My approach is different when it comes to house plumbing - I get a plumber in! :LOL:
 
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