When I walked by the Barth after shutting the engine down, I heard a hissing sound. I popped open the genset access door and noticed this devive which had 2 air hoses coming out of it. Notice the one port with nothing on it. It has air blowing out of it. Why? Is this device broken? I cannot seem to find any hoses that could have fallen off of it. I will post pictures.



Richard

That is your venturi vacuum valve. It pushes compressed air through the valve at the top and then it exhausts to the outside. That is where the dash heat and ac gets its vacuum to operate the flap doors. It would appear to be working properly.

Well that's a relief! Thanks,

Richard

If that venturi vacuum generator keeps hissing until there is no air pressure left in the tank (with the engine off) then it or the regulator just above it is defective. It also may be that you have a vacuum leak somewhere and so in order for the vacumm to be maintained it will keep bleeding air to try to generate vacuum. Both of mine crapped out and I replaced them with an electrical vacuum pump as the venturi generators are no longer available, originally made for Ford diesels.

HTH

Mwrench,

Do you have a picture of your new setup?

Hi Richard, No I don't have any pictures but can get some in a day or two. At the beach for the 4th.

My setup is fairly simple but does require a motorized vacuum pump, I tried the Volvo pump but it didn't last long. It didn't pull enough vacuum when I was at higher elevations and would run continuously.

You probably have another of those venturi vacuum generators in the back to run your cruise control, I replaced my entire cruise control with an unit from a late model Chev truck.

Ed, it looks like my cruise control is electrically controlled.

I discovered another potential cause of excessive leak down the other day. On the front of my Regency near the venturi is a small circuit breaker block with two blade fuses 20A. My son noticed that one of the fuses was crooked and that a bad connetion in the block had melted the plastic. I replaced the fuse after cleaning the melted area and the venturi air leak stopped. Now my tank pressure remains high much longer.

Turns out the fuse was for the high speed fan selection on the dash heater/AC not the vacumn leak.

Sorry for the misinformation.