Air bag won't inflate

[John Padmore]

I was able to get my front leveler working today by cleaning the switch (there is so much good info on this forum!). So I went ahead and leveled the coach to do some work. Now I retracted the RVA jacks because I have an appointment in a couple of hours to drop the coach off for engine service. When I get up to air pressure the driver front air bag isn't inflating (no problem previous to leveling). I tried getting up to pressure then dumping the air a couple of times but no better. Can I drive the coach 5 miles to get it to the service place, or is that a bad idea? Any idea what I can look for? Thanks, as always.....

John

[Joel Ashley]

Probably not a good idea to drive that way, John.  You need to be in full travel mode to be sure your drivers tire clears its fender on turns, and for suspension reasons.  When my air system failed to reach and stay in Travel Mode a year ago, I fully raised and lowered a few times until it somehow miraculously got into a travel height where there was no scary noises coming from under the rig when it moved (yes, there were better options for checking... my bad).  In Bend, the techs found a broken air valve link rod assembly underneath, a common failure apparently from other Forum threads here early in 2012.  I was lucky the thing raised to travel height and stayed there til Bend.

But try fully raising and dumping a time or two (make sure your front wheels are straight ahead!) to see if anything changes enough for you to safely get to service.  Then have your air system checked.  If you encounter too much twist and noise when raising, stop, so you don't damage anything.

Joel

[John Padmore]

Well I tried dumping and pumping the air system a few times (4) with no acceptable results. When I dump air the clearance between tire and wheel well is about 1 inch. After pumping up, the "good" side has 8" clearance and the "bad" side has 4" clearance. I let the cat run for 15 minutes before measuring. Still think I can't drive the 5 miles for service? Just asking...... Thanks for the help......

John

[Edward Buker]

John,

I have had a mechanical leveling valve stick before. The one with the rod on it. I was able to move the coach just a few feet back and forth in a straight line, do not turn as Joel mentioned. By tapping the brakes, to cause some chassis movement, the valve released and then the bags aired up. You could have other issues with the system but this might be worth a careful try as long as you can air up, have the compressor kick out, and hold air without any significant losses.

Later Ed

[John Padmore]

Ed, is there a way to spray some wd40 on this rod thing to get it to unstick?

[John Hennessey]

You may also have a sticky traveling solenoid.  We had to have ours replaced at BCS

[Gerald Farris]

John,
Like others have said, there is a possibility of damaging the coach if the suspension is totally deflated on one wheel. There is also nothing to spray WD-40 on. The highest probability for the cause of your problem is that one of the rubber connectors on the rod that connects the height sensor to the axle is broken. If that is the problem, it is very easy to repair. However it can be dangerous to work on the suspension height controls if you are not knowledgeable about the suspension because you can lower the coach unexpectedly while under it. So do not get under the coach without adequate safety stands for your protection.

Gerald    

[Gerald Farris]

John,
Like others have said, there is a possibility of damaging the coach if the suspension is totally deflated on one wheel. There is also nothing to spray WD-40 on. The highest probability for the cause of your problem is that one of the rubber connectors on the rod that connects the height sensor to the axle is broken. If that is the problem, it is very easy to repair. However it can be dangerous to work on the suspension height controls if you are not knowledgeable about the suspension because you can lower the coach unexpectedly while under it. So do not get under the coach without adequate safety stands for your protection.

Gerald    

[Joel Ashley]

Though I suspect the rubber boot on his ride height valve rod, as Gerald alludes to, it concerns me that he is low on one side and not both, if that's the case.  I say that because doesn't one valve control both sides up front on these coaches, whereas there is a valve for each rear side?  If his front rod boot was shot, wouldn't that affect both front bag sets equally?

Joel

[Steve Huber Co-Admin]

John,
I had a similar problem. Since the front adjustment only controls overall front height, adjusting the front rod won't affect uneven leveling. Check your rear leveling. You can make adjustments there that will affect the front. But, be very careful as you have to get under the rear cross-member just  forward of the axle to access the adjustment rods. If the coach drops, you could get crushed so use ramps to give yourself some height. You can "balance" the rear and front side to side level from the back.
I suspect you have a rear out of adjustment as your front bag is inflating somewhat (from 1 to 4"), just not enough.
Good Luck,
Steve

[Edward Buker]

John,

As others have pointed out you should not get under the coach and spray anything. The typical configuration has one air valve in the front that supplies the front air bags and that is probably working fine. There are two valves in the rear and my suspicion is that one of them has had the adjusting rod slip and is not calibrated properly anymore, given that you come up on the low side but not within proper calibration it would seem. As Gerald points out it could be a broken rubber coupler but my guess is, if that was the case, the side with the bad coupler should be lower with the bags on that side being depleted. It may also be that the good side partially lifts the weak side.

These valves have rods whose mounts are welded to the backside of the differential. What you may be able to do with a mirror set on an angle on some form of handle and a flashlight, is examine the mechanisms from a safe distance the to see if both rods are coupled properly and if the rubber couplers are in tact. This would give you are starting point to discuss the issue with someone who works on suspensions and can bring the proper support jacks to safely get under the coach and work on it.

Later Ed

[Richard And Babs Ames]

If you were level when you stopped odds are it is terrain causing the problem. IE one side of the rear or front axle and tires higher than the other. Driving foward should allow the coach to level itself out.

[John Padmore]

Ok, I had a truck repair mechanic look at the coach. He adjusted an air control valve on the front, and we were good to go! Took the coach over to their shop for Cat service and to have brakes checked. They will do a complete service and check the air suspension also. Thanks to all for your ideas and support.

Johnh