Newell Gurus

Gang,

About a year ago, I had Newell replace the rear air bags on my coach (2003 model).  In August of 2014 I was back at Newell for some other work and we realized that one / both airbags were leaking.  Replaced again.

Fast forward to Jan 2015...I am at Newell and bags are leaking again.

They have now been replace again, but I am wondering what is causing the failures.

Symptoms:
1) There is no obvious damage to the air bags.
2) On one of the failed airbags and possibly on all of the failed ones, there is a metal support piece (imagine the inside of a donut) that came loose.  I will append pics of that piece, but in the goodyear diagram (attached) it is the piece that holds the bottom of the airbag to the coach.
3) Air seems to be coming from bottom of bag, not from fittings.

Here are my questions:

1)  The number on the bags old / new is 1R11-066.  Is this familiar to anyone with a 2000 vintage coach?
2)  Has anyone just had bags start leaking for no reason?  (No checking, no holes, etc)
3)  What could cause a bag to leak around the top / bottom?
4) My shocks have never been replaced (on back) 220k miles...could bad shocks contribute to airbag demise?

Thanks!

bill

http://newellgurus.com/showthread.php?tid=60

this link takes you to my airbag journey

the  1R11-066 is the same one that was on my drive axle. (though i used a firestone equivalent to replace it with)  the tag is different on mine as is the front.  

did you happen to call goodyear or firestone and ask them about failures?  you might try it

tom

Tom,
I'm not sure what I would ask them. I have done research and the only fault condition that *could* be applicable is if the airbag is too short for the application. Newell said that the part that was originally installed was superseded at some point in the past but that the 1R11-066 is correct now.

Any thoughts about the ring? (see picture) That ring came loose on one of the replaced bags. Not sure if that is a problem or that is how they are made.

Cheers,
bill

Bill are you at Newell? We are an hour down the road in tulsa

Bill,

Can you elaborate on the failure mode? Are you saying the ring in the second picture where a finger is pointing came loose? How loose? falling off loose? can spin it completely around loose, of just air leaks between the ring and the bag?

Richard,

In one of the pictures you can see the ring (has a finger pointing to it). That ring came all the way off on one of the bags. If you look down into the bag you can see that there is really nothing holding the ring in. Not sure if it was glued, or friction fit....but it is def apart. On other one(suspected good one), the ring is solid.

I am not sure how to seal the bag to inflate it and understand the failure mode.

Can you take a picture of the ring where it meets the bag, and another picture of where the bag where it meets the ring. I am sorry but I just don't remember what they looked like on the inside.

If it is breaking loose like that I can only imagine a couple of scenarios. One, do you raise the rear all the way up very often? For example, I learned the hard way that the aux air compressor will run to it's max while the leveling system is still on. I blew a tag air bag by leaving it in level and compressor overinflating the bag.

Second, check the rear panhard bar. If the coach is moving side to side on the suspension it would put a side load on the bag that is it not designed to handle.

I find it hard to think you have had a bad run of air bags to result in three failures in the same axle. Something may be amiss. Your shock idea may be worth looking into. You can't really tell if the shock is good or bad just by taking the lower bolt out and tugging on it. BUT, you can tell if it is completely shot by doing that. I would at least check it out while it's on the pit.

Bill: I hate when this stuff happens. I would be taking a long look at how the bag could become overextended. That configuration is designed for the bottom end of the bag where it is embedded in the bottom plate to be pointing down. An overinflated bag will be pulled upwards against the rim of the bottom plate and puts mechanical stress on the joint in addition to the air pressure stress. I believe there should always be a downward fold this style airbag.

On my 77 coach all the tapered cones on the bottom were loose and never leaked. I replaced the bags because they were getting cracks in the rubber.

What did Newell have to say about the cause of the failure?