While driving that long straight road from WY to SD (16) on our way to Custer, I had a chance to monitor my dash air gauges for longer than just a quick glance every once in awhile.
Here is what I noticed. At 60 MPH both the fwd and rear dash gauges would cycle from about 100 to 125 PSI constantly. A few seconds to 125, then a few seconds to 100. I can't ever recall seeing this happen before. I did notice when the eng was at idle this did not happen!?
The other thing I noticed, when we stopped at Shopko for some supply's, I did my walkabout around the coach checking tiers and tow gear and noticed the air dryer was cycling about every 2 minutes! By that , I mean that it would exhaust every 2 minutes. I know that hasn't happened before.
After some thought on this, I'm thinking my D2 gov is not working as it should. BTW, I did check around the air dryer for leaks but didn't find anything.
I hope I expressed myself well enough so that I can get some feedback on this problem.
I have had the governor cause purge issues in the dryer. Most times it caused either long purges or would open the purge and leak until the truck shuts off. I don't know what air dryer you have but I have seen the valve start hanging up too. Based on your symptoms I would start with the governor.
Uhm...did it occur to you to check for air leaks?
That's one of the first things I did Krush. With the quick cycling you'd think there would be a massive leak that one could hear.
I noticed that the air gauges are reading 20psi difference; is there a reason to beg concerned? I had D2 governor replaced and the new one was defective so the old one was reinstalled. The gauges read 120psi and 100 psi.
John, what gauges are you talking about? Mine or yours? Mine are the same.
I would look at that tank that is reading low. They should be the same.
John,
How long has this 20 PSI difference been going on?
Need to determine if this is a gauge issue (more likely) or a real 20 PSI difference in tank pressures.
Swap the air lines going to the gauges,if the same gauge is still 20 pounds low you have a bad gauge, MAKE sure you drain the air system before you do this swap.
It started after Bern'd replaced the dryer along with the D2 governor. The replacement D2 was defective as it would build air pressure until one used the brakes and then go to 35psi. So Bern'd changed the D2 back to the one that they took off.
I would look at the air hose going from the governor to the drier and the connection at the drier. Also, the drier purges every time the pressure reaches the governors max (120) in your case. Seems like a leak related to the governor.
Thank you Twig for the possible cause and what to check. Not near the coach but will check as soon as I can get away and let you know what I found out.
Good call Bill,,,, Both tanks are filled from the same air line from the wet tank. His problem is a bad gauge.