TimW Wrote in message:
What sort of fitting is
needed for black plastic pipe? I had an idea that I could cut the pipe
and maybe fit a stop cock with the stop cock open and the water flowing
through, then turn it off, then deal with the trough valve. would that work?

As long as you get a full bore valve it shouldn't be a problem.
I've done it indoors without making an enormous mess. It's
helpful to fix a bit of hosepipe or similar to the downstream
side of your new valve temporarily to direct the flow of water
well away from you whilst you're tightening the fittings


Tim


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