Community Forums

walt2137 · 07-26-2018, 06:26 PM

Above the left rear axel on the frame, but if its leaking the air escaping will tell you where you are having trouble wherever it is

tc914-8 · 07-26-2018, 07:09 PM

Ok just ran a few diagnostics, chalked the wheels, released the parking brake, pressure held at 100psi no movement. I started the coach with p brake on, compressor kicked on popped up to 130 and shut down, pressure crept down to 120 and held solid. Released parking brake, wheels chalked, pressure dropped a bit but held. Ran several tests, dump valves, P brake on/off compressor kicked in 100 cut out 130, pressure crept down to 120 in 30 Sec. Then held. Next test will be a road test. I’m heading out this weekend, I’ll give it the same diagnostic run thru and see if anything changes. Maybe I jumped the gun, I don’t think rolling down the road with foot off the brakes would be use any air ?

slickest1 · 07-26-2018, 07:36 PM

My coach was doing the same thing and it was the air dryer. It was leaking out the exhaust port after it purged. I am on a road trip right now so I just unhooked both in and out lines and joined them together and bypassed the dryer and it does not loose any air at all now. I will replace the dryer next week when I am not travelling. Mine just had a new filter and such put in when I bought it this spring, so I will just replace it.

96 Wideglide · 07-26-2018, 08:45 PM

Dennis, your near me. Where would be the best place to get a replacement dryer?

tc914-8 · 07-26-2018, 10:38 PM

I got mine on Amazon very reasonable and here in 2days w prime

CountryB · 07-27-2018, 04:06 AM

Quote:

Originally Posted by tc914-8

Ok just ran a few diagnostics, chalked the wheels, released the parking brake, pressure held at 100psi no movement. I started the coach with p brake on, compressor kicked on popped up to 130 and shut down, pressure crept down to 120 and held solid. Released parking brake, wheels chalked, pressure dropped a bit but held. Ran several tests, dump valves, P brake on/off compressor kicked in 100 cut out 130, pressure crept down to 120 in 30 Sec. Then held. Next test will be a road test. I’m heading out this weekend, I’ll give it the same diagnostic run thru and see if anything changes. Maybe I jumped the gun, I don’t think rolling down the road with foot off the brakes would be use any air ?

Last test, with air pressure at full, parking brake released, shut off engine then step on brake pedal and hold pedal down. Air pressure should drop some but hold steady. If the pressure keeps dropping you have a blown brake diaphragm.

Driving down road with foot off brake the only thing using air is the air leveling (air enters and exits air bags as coach adjusts to road changes). But if that was leaking you should hear it when stopped too.

walt2137 · 07-27-2018, 05:41 AM

Quote:

Originally Posted by tc914-8

Ok just ran a few diagnostics, chalked the wheels, released the parking brake, pressure held at 100psi no movement. I started the coach with p brake on, compressor kicked on popped up to 130 and shut down, pressure crept down to 120 and held solid. Released parking brake, wheels chalked, pressure dropped a bit but held. Ran several tests, dump valves, P brake on/off compressor kicked in 100 cut out 130, pressure crept down to 120 in 30 Sec. Then held. Next test will be a road test. I’m heading out this weekend, I’ll give it the same diagnostic run thru and see if anything changes. Maybe I jumped the gun, I don’t think rolling down the road with foot off the brakes would be use any air ?

That is strange also the drop from 130 to 120, another posibility is the PSV ( pressure safety or relief valve) leaking .

JLHoughton · 07-27-2018, 06:35 AM

I have had mine do this as well. Was on the interstate and the road was like a washboard and was causing the airbags to deflate and inflate, Once back on smooth road it settled down and there was no longer a loss of air pressure. I do have a slow leak at the Air Drier purge valve that I need to address. In cold weather it will leak down and purge with the engine running but not leak when engine if off.