I have battled for several months to get the washers to work, having tried replacement Trico pumps; replacement vacuum switch; replacement rubber tubing; thinking that in all probability, the diaphram in the pump must have perished and battled to find an alternative.
Eventually, I checked the vacuum pressure from engine block and found it to be good. Then resorted back to my original pump; bought a new vacuum switch and replaced the rubber tubing with a more rigid tube and operated the system free from the dashboard switch, to find it all worked perfectly !!! Problem solved after all this time.
It was the tubing that was the problem. The previous rubber tube could not withstand the vacuum suction and was compressing as a consequence and preventing the suction from reaching the pump !!
Hope this may help anyone out there
Peter Bradfield
