Community Forums

Jubilee 45 · 07-23-2019, 12:45 PM

Hi, called for mobile service. Lost air rear then front. Emergency brake won’t disengage. Is there anything o can do?? Thank you!!

**CountryFit** · 07-23-2019, 01:02 PM

When you ran engine, did you hear anywhere hissing?
Cummins air compressor failure isn't unheard but uncommon.

Here is a case reported by a member
http://www.irv2.com/forums/f115/cumm...re-130132.html

Jubilee 45 · 07-23-2019, 01:22 PM

No hissing. I ran the motor. Then turned off. Listened. No hissing.

Kodiakan · 07-23-2019, 01:25 PM

The brake is locked on for a reason; if you don't have air, you have no brakes. This is the same reason when we start our coaches we wait for them to air up to a decent level before taking off. Others will chime in on what to do but as for me, I just wanted to say, don't somehow get the brake to disengage unless you have plenty of air for the brakes.

BrianGlenn · 07-23-2019, 01:36 PM

Mobile mechanic is best to troubleshoot and fix issue. We are only armchair mechanics here.

Some coaches have a connection to add air to system if compressor supply is NFG. This assumes air tanks are holding and no leaks. This is ONLY to help move coach to safe area under controlled operation. Heavy tow operators can cage the service brakes if needed to tow ONCE the coach is secured to tow vehicle. Do not cage service brakes to move the vehicle under own power.

twinboat · 07-23-2019, 01:42 PM

Most likely the air dryer purge valve stuck open. Many of them have threaded discharge ports that a pipe plug fits. That gets the system working until a new air dryer is installed.

You won't hear air leaking unless you rev up the engine, but then the noise may drown out the sound of the leak. If you turn off the engine, it stops pumping so no noise.

Mobile guy will check that first and the the lines back to the compressor.

8.3Oilbuner · 07-23-2019, 01:43 PM

Good afternoon Bill; Sorry to hear you are have problems with your County Coach. As others read your post I am sure they will be asking, your air pressure gauge on the dash for front and rear air tanks shows no pressure at all or just a small amount like less than 25#? I think, not sure, you have a Cat. engine in your CC. I am not sure how the air compressor is driven if you have the Cat. engine. I hope someone here with a CC will respond soon to give you some ideas. Sounds like you have a mobile service on the way. Let us know what the problem was and how they fixed it. Good luck!

C&SL · 07-23-2019, 01:49 PM

Have you checked your Air governor?

C&SL
05 Sig

Jubilee 45 · 07-23-2019, 02:21 PM

Update. Front air holds at 50 PSI, rear zero. Mobile service will be here in 30’. Thanks everyone. I appreciate your comments.

twinboat · 07-23-2019, 03:29 PM

Quote:

Originally Posted by C&SL

Have you checked your Air governor?

C&SL
05 Sig

I'm very familiar with air systems, with training and years of experience.

How would he check his governor in this situation ?

C&SL · 07-23-2019, 05:14 PM

Quote:

Originally Posted by twinboat

I'm very familiar with air systems, with training and years of experience.

How would he check his governor in this situation ?

Well, I never said it was not the purge valve. I suppose I should have said, have you checked if there is air coming out of the exhaust port on the governor?

As you know, the only time air is supposed to come out the exhaust port is when the governor is transitioning to cut-in, when it has to dump the air in the unloader port to let the compressor start to compress again.

C&SL
05 Sig.

**CountryFit** · 07-23-2019, 05:16 PM

Quote:

Originally Posted by twinboat

I'm very familiar with air systems, with training and years of experience.

How would he check his governor in this situation ?

Always enjoy reading your posts; very informative and always hitting the nail on the head

.

twinboat · 07-23-2019, 06:41 PM

Only the small amount of air, that was holding the unloader valves open on the compressor and air dryer will exit the exhaust port of the governor. A quick tiny puff of air.

I suppose the governor could fail somehow that would cause air to constantly escape from the governor exhaust port, but I'v never encountered it.

Quote:

Originally Posted by C&SL

Well, I never said it was not the purge valve. I suppose I should have said, have you checked if there is air coming out of the exhaust port on the governor?

As you know, the only time air is supposed to come out the exhaust port is when the governor is transitioning to cut-in, when it has to dump the air in the unloader port to let the compressor start to compress again.

C&SL
05 Sig.