[Fred]

Open doors -rear- right hand side of engine- is air compressor. On top of it part of the assembly is governer. A easily replaceable item. You will have plenty of warning of problems and they are available at truck stops and parts places everywhere. Common to trucking industry. I have not found it to be a high maintance item. Bob Sorry (brain lapse) back not top. Sometimes you just need to be looking at it!

[Ray]

Andre,

Any truck place will have them, they’re cheap. Common item with Napa also. They’re adjustable, you can turn the air up or down, but the spread between the cut in and cut out is about 30 psi. So it will usually cut in at 90 and off at 120. I like 125..

[Archived]

Prevost calls for 120 to 125 upper limit. You can adjust the governor if you need it, but I believe the compressor relief valve is set at 140 so at some point if the governor is set too high you are going to pop open the valve.

There is no adjustment on the differential between cut in and cut out pressures.

[Archived]

Thanks to all,

I found it on the back of the air compressor. For whatever reason, I was under the impression it would be bigger. So I never relized that the part on the back of the air compressor was what I was looking for. Tom, your picture sure made it easy to find.

Thanks again,

[Archived]

Sorry about that. Sometimes you just need to be looking at it.(me) I have brain lapses it seems when trying to remember. Bob