Mechanical advice - air pressure issue

Check your bleed off valves. Maybe they are leaking a little until they had enough pressure to close them

 

Seems there's something blocking the line into the tank

 

You sure that's a vent and not a port,that a plug fell out of?

 

Then there is a problem getting air into the truck tank

 

We had one hell of a time with one truck and the lack of building pressure. It was giving issues with the governor tripping at 139 psi, and then not cycling so we replaced it and the new one gave us fits, not building air pressure. We replaced the governor, then thought it was the air dryer (cummins system so it had an extra line going to the ad-9), then we looked at the tanks, lines and all of it. The truck was down for two weeks, it was losing too much money. I had it towed to the nearest freight liner dealer, they did more, replaced the compressor but being in the shop at this point with 15 hours of work there, nothing was getting done.

So I had the truck towed back to the yard and was ready to put it for sale. I started to tinker with it out of frustration and took the governor off, compared to the old one - nothing different. I messed with the replacements that were in the tool box, all looked the same. Near the end of the day, i was looking at the newest one I took off the truck. I decided to remove the plug from one of the two ports on it, move it to the port that control line that went to the ad-9 and moved that fitting to this now open port to see what happened. I put the thing back on the compressor, started it up and .... It built up pressure ... Popping off at 125 or so psi.

I don't know why this was the case, I spent 30 minutes on the phone with the dealer, another 30 minutes with bendex telling them what happened which they could not or better out would not tell me why. So in the end I ended up with one hell of a loss from it, 5 brand new governors and nearly a new air system on the truck.