[Fulltiming]

Tony, your coach was just a few after mine so I would think it should have a 120 volt AC air compressor. Mine does not have a 12 VDC compressor since I don't have air toilets or air pocket doors. My 120 VAC compressor is in the front right compartment with the generator blower motor. My only switch for the 120 VAC compressor is on the dash.

[BusNit]

I am following this as my coach too, loses aux air in about 15 min. My compressor is 120v and up front in the right bay next to wheel. I did find a slight air leak at the generator airbag regulator and one underneath right above the 6pack. Those two are not enough to cause the massive leak.

[Tf175]

My governor is a Bendix D-2 ,
P/N 275707 N . 105/125 psi .
The original threshold was 90 , I think.  
Governor is adjustable,  but I haven't changed the setting it  came with .
Chris

[Tfrazier]

Thanks everyone for the feed back. Regarding my compressor. Mine is in the front right bay with the generator blower as well. I checked it out (should have done that in the first place) and it is an Emerson 115V (per the label). I think I got confused about this because mine has the check valve set up that Richard mentioned. I attached a couple of pics.
I ordered a new governor this morning.

    [    

[Tfrazier]

Forgot to mention. The part number was worn off my governor but I could read the D2. Also the rating in mine ended in 125psi. Couldn’t make out the first number but looked like it could have been 100.

[smagown]

That look's very much like a Gast compressor.

[BusNit]

And what a new Gast compressor looks like within a refurbished bay

[ccjohnson]

I have my check valve plumbed on the other side of the drier. That keeps system pressure from being able to bleed off through the plastic bowl.

[Tfrazier]

To recap: After I completed the AD 9 install, I started the coach and it aired up to 130 and purged just as it should. I thought I was done and took a break before I started my clean up. Went back to the coach an hour or two later and both the brake and supply sides had dropped to 50psi. When I started the coach the Brake supply side stayed at 50psi, while the Supply side dropped to zero and neither side would not come back up. I tried this several times with the same results.

Got the new check valve on Thursday. For sure the old check valve was bad (see pics). I Installed the new check valve on Friday. Fired up the coach and the air built up to 130 and purged. In an effort to recreate the scenario described above, I fanned the brakes to bleed off the air down to about 50psi. This time the pressure built back to 130 and purged (Good sign). I did it again and had the same results so now I am feeling confident that the new check valve fixed the problem.

Today, I went back over to the coach. The Brake side was at 50 and the supply side was at zero . After saying a few choice words that I can't repeat here, I started her up. Both sides built pressure and went back to 130. So at least the issue of building up the air pressure seems to be solved. However, I still have to do further investigation on where this leak is coming from. Since it wasn't there before, one would logically think that it has to be coming somewhere within the confines of the AD 9 install and all of fittings that I touched during the process. I have checked, double checked, triple checked everything that I came in contact with. I have used an entire bottle of bubbles on the fittings and the AD 9. I can confirm that there is no air coming from the purge valve or any connection point on the dryer.

The weathers is going to be too crappy to do anything tomorrow so it will be next weekend before I can get back into it. I will have a new governor by then so I'll install it then. In the meantime, if anyone has any ideas, let me know.

           

[rheavn]

A leak down tester is the best way to identify which air line is leaking. Tool is described here.

http://newellgurus.com/showthread.php?tid=2705