I had that problem with one of mine. The switchover valve is small and can get stuck. I work on mine on the bench where In can see everything clearly. I use my central vac to power it.


1951 GMC 1 Ton Flatbed -- It is finally on the road and what a great time I have driving it!
1951 1 Ton Completed


My Chevy Master 4 Door is on the Road!