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?