Air Leak From Exhaust Port of The Vaccuum Venturi Assembly

[Carl Tesch]

I am an instructor in a Diesel Technical school. We are working on a Newell Motor Home which belongs to the Governor of South Dakota. We have all the information we need to work on the brakes, engine, gen set, etc. ; but very little technical information on Newell itself.

I am trying to repair a constant air leak from the exhaust port of the vaccuum venturi assembly which I think supplies vaccuum to the heater/defroster blend doors. I have purchased a new venturi assembly and it acts the same as the old one. I have used a hand vaccuum pump to supply vaccuum to the "S" port but this still does not close the valve. Any suggestions? Can you tell me how this device is supposed to work?
thanks for your time and attention.


Thank You,
Carl Tesch