Community Forums

FIRE UP · 09-28-2021, 07:35 PM

Question for you boys,

So, based on what we've seen here in the last few posts to this thread, it is possible for the governor to not regulate the pressure to the given or set amount, correct? If that can happen, and, our basic air systems are normally topped off around 120 to 130 psi, then wouldn't safety pressure release valve, sitting on the side of the air dryer, take care of the excess pressure BEFORE that excess pressure damages any component of the air system?

Our system(s) as stated, are supposed to run at or around 120+ psi and, the pressure safety valve, if I recall, is rated at 150 psi. I don't know what any and all hoses and air lines are rated at but, I would definitely assume that pretty much ALL of them are rated for at least higher than 150 psi, correct?

So, if that might be the case, and the pressure safety valve IS the main safety of the system, then I would think that, in the cases where the the OP was having excessive pressure, as indicated on his gauges, that the safety valve on the compressor has also failed, correct? Or do I have all this all screwed up? Especially since the safety valve is rated for only 20 psi higher than our normal operating pressure.
Scott

twinboat · 09-28-2021, 08:29 PM

Yes, the safety valve should control the pressure in a reasonably new or well maintained RV.

This is a 1999 RV.

Djmckee · 09-29-2021, 02:45 PM

New update
All lines have been checked they all got to go. Using compressed air and compression tester I was able to pressurized them they all hold air

Next I went to the compressor the discharge line going to air dryer has very little pressure coming from compressor

I removed the Governor with it removed I have the same result very very little pressure

Now I believe I could have a stuck unloader valve in the compressor.

Any other thoughts?

tompands · 10-04-2021, 03:50 AM

Quote:

Originally Posted by Djmckee

New update
All lines have been checked they all got to go. Using compressed air and compression tester I was able to pressurized them they all hold air

Next I went to the compressor the discharge line going to air dryer has very little pressure coming from compressor

I removed the Governor with it removed I have the same result very very little pressure

Now I believe I could have a stuck unloader valve in the compressor.

Any other thoughts?

You might need a new compressor. If it's not building air, the compressor is probably shot.

twinboat · 10-04-2021, 05:34 AM

You may be able to remove the unloader valve to take a look.

Google the model of the compressor for a parts breakdown.

Djmckee · 10-05-2021, 04:03 AM

I have determined that that compressor is bad not building the pressure needed. A friend remove the unloaded and compressor still would not build the pressure. I am currently trying to find one or a rebuild kit. The compressor is a 3558215RX Cummins has only one available for $1650

Next step is to replace the compressor then I still need to find the issue that caused the compressor to overwork

RonAz · 10-05-2021, 05:11 PM

I have found that the symptoms of a bad governor is excessive cycling of the compressor with pressure staying high. Example is 105 to 120 off and on continually

tompands · 10-06-2021, 06:34 PM

Quote:

Originally Posted by Djmckee

I have determined that that compressor is bad not building the pressure needed. A friend remove the unloaded and compressor still would not build the pressure. I am currently trying to find one or a rebuild kit. The compressor is a 3558215RX Cummins has only one available for $1650

Next step is to replace the compressor then I still need to find the issue that caused the compressor to overwork

That is probably a HOLSET from Cummins. If you look around and make some phone calls, I'm sure you could get one cheaper than $1650. That's a very high price. i just did a quick online search and found it for $1300. You could also do a Bendix compressor which would be a lot cheaper for you. You don't have to replace it with a HOLSET. A air compressor is just a air compressor.

Djmckee · 10-21-2021, 06:53 PM

Okay I found a rebuilt compressor in Missouri for $350 will be ordering tomorrow I will give a update when I get it changed.

Big thanks to everyone you guys helped me a lot. I knew nothing on the air brake system. I would still be lost without your help
Thanks again