"Chris S" wrote in message
...
Advice please. I am connecting a water supply hose to washing machine
but getting a slight leak.

http://www.toolstation.com/images/li...bbig/32532.jpg

The hose is brand new and the rubber seals inside the screw heads are
undamaged. The screw part of the hose and the screw part of the washer
are both plastic.


(1) Is the rubber seal at the end of the hose supposed to be
sufficient to keep the joint water tight?

I do not think I am over-tightening the joint. If anything I may be
under-tightening it as I'm tightening by hand and, at my maximum,
probably could give it another 1/4 or 1/2 a turn.

(2) Is it good practise to use PTFE sealing tape on these screw
joints? Or is the use of tape a sign of a poorly connection?

No PTFE tape on plastic screw joints, all it does is deform the threads and
water still leaks.

However I have had instances where a smear of Fernox LS-X on both sides of
rubber washer and even lightly on the thread has finally sealed things.

One hose I couldn't seal was due to a blob of gloss paint on the rear of the
thread of valve, due to when the kitchen was replaced ,that just lifted the
plastic thread off the thread and leaked, Only obvious when I removed the
valve for replacement.

Other than that you can get replacement ends for the hoses that jubilee clip
on if hose replacement is not possible as some appliances the hose
terminates inside the appliance in a manufacturer specific connector.