The problem is caused by the rotary contacts at either end of the hose. I carefully drilled small holes into the cover fittings and squirted in Servisol electrical cleaner and lube, available from Jaycar in Australia. Used the small tube extension supplied. It solved the problem for a while, but had to repeat the spraying about every year or so.
I would like to change the circuit to keep the top speed hard wired, but have not found out how to do this.
Rex S.
Rex Swensen, September 2014
