Hi
Just an update, have fitted the new solenoid and all works perfect.  Old one was quite rusty
Didn’t hVe to change anything, fitted into same slots and connectors
Cost £25, on Amazon , supplier was in Cardiff
As a by,  the hand pump lifts the keel in about 7 mins and the valve release drops it as normal.  So you could actually survive if electrics went, although would have arms for a weightlifter
I will see how this solenoid fares this summer, fingers crossed
Barry
Sulito