How to seal a leaking end cap?

[yadnom1973]

I had a small sink in the corner of a room I’m using and it was in the way so I removed it. I cut the hot and cold pipes and went and bought something to cap them with. At the DIY shop I bought two of these little plastic end caps that seal using the pressure in the pipe.

When I turned the water back on the hot pipe sealed up perfectly but the cold did not. The end did not pop up and water started to dribble out the side of the cap. It was as if there was not enough pressure in the cold to make the little cap work properly.

so I wrapped it up with a load of the rubber sealing tape and it did the job for a few months but today there’s a drip, more than a drip, a little spray. I got down there and wrapped more round it till it looked like a rubber ball on the end of the pipe and it’s stopped for now but I’ll need to deal with it in the near future so I’m wondering what’s the correct way to seal a pipe like this?

I’ve tried googling this but all I can find is how to fix leaking I joints but there’s no thread on the top to apply all these compounds to just the cut end of the 15mm pipe.

Any advise appreciated.

 

[Ian]

If this is a 15mm copper pipe you could use a push-fit endstop to get a good seal:

https://www.screwfix.com/p/jg-speedfit-pse4610wp-stop-ends-10mm/39981
https://www.toolstation.com/shop/p52927

Is that what you're using already? They should work well as long as there was a clean cut and the pipe was undamaged.

I prefer using brass compression fit endstops, but if you're not familiar with compression fittings then the push-fit method is much easier and should work.

 

[yadnom1973]

That was the advise and the product I got down the shop first time round and I cut and filed the pipes but as some people have pointed out I did not remove the paint. Ether way once The water was back on there was a small dribble coming from one of the caps. At the time it seemed to me that it was due to not enough pressure in the pipe but as no one in this thread has commented on this and the water had enough pressure to find its way out after a month or so I’m presuming this was a flawed assumption.

I was however introduced to the compression joints a few posts up, these I did not know about before so I ordered two of them as a more permanent solution though I’m not to eager to remove both caps. Messing with something that’s not broke makes me uncomfortable.

Learning how to fit these compression end-stops also seems valuable in it’s self.

 

[TommyD]

Buy a roll of plumber's sand-cloth and get the paint off the pipe, and try the cap again.