1999 Holiday Rambler Air Bag System

[bandm]

Hi a couple of questions on this very simple non automatic system

1. When parked and dumping the air it stops at about 60 psi in the secondary tank. I think that is the PPV working as it should. But then in less than 8 hr the system will show zero pressure on the secondary tank which feeds the air bag system the primary system holds air fine.

Ok so I wonder if the ride height valve is asking for air and it should get none if the PPV is holding ??.

By design would the ride height valve (Barksdale) exhaust air when it is in the demand cycle ie coach lower asking for air

NOTE this is a Monaco dump system and takes the air from the small blue lines that go from the ping tank (secondary) to the ride height valve

I have soaped every connection and can find no leak and can not see a leak at the ride height when down at the 60 psi level.

2. Going down the road we consume enough air that the compressor kicks in every 10 min or so. More so when the road is rough. I assume this is air from the bags exhausting due to more than normal movement. ? dose this system exhaust out the ride height valve ?

Rides well corners ok etc BUT if the shocks were getting weak perhaps we are overworking the air bags and causing the exhausting ?

No leaks or oil showing but close to 90k on the Bilsteins

Note on the service at Freightliner last time they rated the front ride height valves as slow to level. The ride height was checked and found ok

Thanks for your help and comments

[dickandlois]

BandM,

A reading of 60 psi after dumping is because of the PPV(s).

The drop in pressure to zero over 8hrs. is a little faster then some coaches. When you dump the air and are walking around in the coach with out the jacks down the leveling valves are going to slowly exhaust air.

The air dump valve is always open when the ignition is off, the reading of 60 psi is due to the PPV, between the Primary and Secondary Air Tanks. Once you have dumped air. The valve closes when ignition is on and you reset the dump valve to Auto, this enables the ride height.

You mentioned that you could not find any leaks.

The question I have is are the air ride springs OEM. They may have some dry rot this causes small pin holes in the air springs. As the rubber in the Air springs drys out it also effects the quality of the ride. This happens so slowly that we tend to not notice the slow decline. So you might try to spray some soupy water on them and look for leaks.

Regarding the Shocks. Do you notice any porpoising while driving down the road ? Shocks with 90K on them do not owe you anything.

Rich.

[bandm]

Hi,

This is a very basic system with no auto level or dump. You park, dump air, level with jacks and your home. I have soaped the bags and the total system and find no leaks.

With the air at 60 PSI I figure there is some leakage from the PPV and that's where it goes. So I think I will change the PPV which goes to the air bag manifold.

Going down the road is still one to figure out. But the height control valves do exhaust air in a big bump like we see on interstate 20 in Miss. So I think that is a major consumer of air.

Your right the shocks don't owe us a thing so will change them and see if it helps dampen things.

Thanks Rich

[Walt2137]

The air compressor cycling every 10 minutes could be lots of things but one thing to check out is the inversion valve because when you are in the park mode the leak will not show but going down the hwy it will leak. To check, air the coach up chock the tires shut the engine off do not engage the park brake and listen for a leak at the rear axle.