Airbags and self-levelers

fangthorpe · 08-01-2003, 10:40 PM

I've got something weird going on with the rear airbags in my '92 300LE. Front bags are gone, replaced with heavier springs and swaybar, and handling on the road is not at issue. The coach rides a little nose high, I guess because the springs are new, and I'm reluctant to lower the front, as everything is aligned and it really goes well. Rear bags run at 75 PSI and seem to behave on the road, except that when the self levelers jack up the rear to auto level the coach for the night, the rear bags bleed down and drop the tail again, but drop it lower than it is on the road. When you shut off the auto levelers, you can hear the bags bleeding down. I can't seem to get it to stay level. Do I have to raise the ride height gizmo, even though I like the handling now, or is there some way to override the bleedoff so I can add more air for the night and get the tail up.? I've tried going back after the bleeding stops and turning the ignition back on and letting the pump run until it stops and that helps some, but not enough to get the bed level. Help.
Thanks, Andy

87MH · 08-02-2003, 12:30 AM

Andy:

I think the air bags are doing exactly what they are supposed to do. When the hydraulic jacks raise the frame, the air leveling system senses that the front is effectively "lowered", and bleeds off air from the bags to compensate. Of course, when the hydraulic jacks are extended, the suspension system is unable to follow the directions of the air level sensors, so the bag air continues to bleed off.

On my 87 345 sometimes the system will bleed completely off when supported by the hydraulic jacks, and the springs on the drive axel actually make contact with the upper flange of the frame when lowered down off of the hydraulic jacks.

Like yours, I have found that for the air leveling system to bring the bags up to a pressure that will level the beast, some movement of the unit must occur, 50 feet or less usually brings the air leveling system up to an acceptable height.

Part of the camp departure procedure is, as soon as I clear the campsite, to exit the MH and do one more walkaround, checking the camp area itself and also the undercarriage for proper bag inflation.

PeterH-79MH · 08-02-2003, 05:16 AM

Quote:

Originally posted by fangthorpe
....., or is there some way to override the bleedoff so I can add more air for the night and get the tail up.? .....

You could add 2 solenoid valves after the leveling valve and before the bags. They would be connected to your 12 V compressor source, which would mean they are deenergized when the ignition is of and seal the air flow from the bags. Once you turn the ignition on, the valve opens permitting flow through the valves.

Special order through a Parker Hydraulics Distributor, appr $40.- ea

Part#: C2LV1 251DC11AH

kzener40 · 08-03-2003, 08:10 AM

I find that if I park my MH after driving it with the back airbags full and then after some time has passed (days) walk in the back of the coach all of a sudden the airbags start releasing the air and I can feel the back end start to drop. Is that normal? Should the airbags stay inflated after you're done driving? Is there somekind of system that bleeds the bags and if so should when should that happen?

Thanks
KEN

jfuller · 08-11-2003, 10:41 PM

I have found that once the bags bleed off air to the point where there is air need from the tank my bags will deflate. The reason I think is that the leveling valve was leaking. This cause the tank to bleed off. Then when the laveling valve open to call for more air it just leaked out the valve. I have been trying to find a new valve. I have called Airstream with no help. Does anyone know where to find a new valve? or what the number is. I have found a Haldex valve which looks like it will work. But I am not sure.

My compressor runs all the time and it is unable to bing the tank up to the 100# of pressure need for the bags.

PeterH-79MH · 08-12-2003, 05:51 AM

This valve also looks like it would work, but probably needs some mods.
Ridewell leveling valve

wb13798 · 08-12-2003, 07:31 AM

fleet pride has the valve and the cost is $34 or the airstream dealer in jackson mississipi has them for $225 same valve. you should be able to get the valve from any heavy truck patrs dealer as tracktor trailer rigs use the air valves. lol
al

jfuller · 08-12-2003, 10:16 AM

Thanks for the info.....Is there a model number on the valve?...
I will make some call today...thanks again