[A/S] water drain valve repair

["nickcrowhurst" <NickandSandra@xxxxxxxxxxx>]

Below the sink unit in our 1988 Excella 25 is a small access hatch 
which conceals the drain valves for the grey nylon cold and hot 
water lines. I managed to break the valve off one of the tubes. 
There is insufficient space to get my hands down the hole to effect 
a permanent repair (a stainless steel screw in the end is holding 
for now), and it looks as if a proper fix will involve replacing a 
whole section of pipe with a new valve at the end. This pipe 
disappears under the floor, crosses the trailer under the shower, 
and re-appears by the wash-basin in the centre bathroom. It might be 
possible to fix a new pipe to the old, and use the old to draw the 
new through this route. Past experience tells me there are good 
chances of this method failing. My smallest grandaughter has small 
enough hands to do the job, but at 18 months old, she has more 
important matters on her mind :) Any suggestions, please? Nick