Governor for air dryer

[Party Barge]

Does anyone know where the governor is located on the xc chasis. My air dryer which was rebuilt by frieghtliner in march is purging to the point that I got below my 65 psi min. I'm going to rebuild the air dryer again myself, but the trouble shooting guide refers to the governor as a potenial problem?

[Pigman]

I'm not sure what you're describing. Can you expand on what you're seeing and especially hearing?

I had a problem where the air drier appeared to be purging, but in fact the problem was a crimped air line between the drier and the forward air tanks. This gave me high pressure stationary, but low air when using brakes and other issues. Watertown, NY Freightliner at first thought it was the drier valve, but a change there didn't help. Finally they traced it to a crimped line on the RH frame rail above the fuel tank. An additional symptom I had was that when stationary and air was building up it went to about 130-140psi. Since the gauge was so hard to read it went unnoticed, but I did find it was hard to release the emergency brake with one hand. Air holds it set.

John

[J Walker]

A pressure relief valve would be on the air drier and the governor would be on the compressor. On my Midland drier I have a pressure relief valve on my drier, and each time I get a new kit a new valve comes with it. I have never replaced the original valve since it is working fine, but I keep the valve handy in case I need it.

[dengraham]

Bob,
My friend just had to replace the pressure relief valve. They used to use 150 lb but now are using 200 lb valves. Call Freightliner; they may just send you a new one.

[Party Barge]

As it turned out, I researched purchasing a rebuild kit in my area and it had to be ordered. Since I had the dryer rebuit 5 months ago at freighliner LV I called them. I bypassed the dryer as instructed and took the rig up for service. The determination was a defective dryer and it has been replaced, all seems great except some $$$ and I'm watching the performance of the new dryer. The coach is loosing air when parked overnight, which it did not do before this issue popped up.

Going back to look at the rig this week with a spray bottle of soap suds.

I found out where the governor is located. I is on the motor just above the compressor. I has three tube going in to it. On my rig i need a mirror and a light to just see it.

[dengraham]

Bob,
The pressure relief valve is also located at the bottom of the drier. They sometimes "pop" because of a surge in the air pressure. If a small amount of dirt gets into the valve they will "leak" slowly overnight, or, they can just plain keep leaking and pull your air down to 65 lbs. The real qustion is whether or not they also changed the valve when they changed the drier??
On my own coach the governor keep "popping off" but is was one of those three lines that had a bad air leak (caused by a hot slag from the welding done at the Winnebago factory). It finally burned out the whole compressor. I hope you find your leak.