Driving with failed Air Spring

[budwilson]

Please help me and educate me on this. What I understand is when you inflate the airbags you raise the body off the frame and when you deflate the airbags you lower the body down. Isn't the engine and transmission attached to the frame and not affected by raising and lowering the body? If my understanding is true how does the drive shaft angle change? Please forgive my ignorance, but my old mind doesn't understand.
Thanks for your patience

[wolfe10]

Originally Posted by budwilson

Please help me and educate me on this. What I understand is when you inflate the airbags you raise the body off the frame and when you deflate the airbags you lower the body down. Isn't the engine and transmission attached to the frame and not affected by raising and lowering the body? If my understanding is true how does the drive shaft angle change? Please forgive my ignorance, but my old mind doesn't understand.
Thanks for your patience

Transmission output IS "frame supported" (above air bags).


The rear axle is NOT. So, the drive shift connects "above air bags" to "below air bags".



The air suspension raises the frame to the correct height.

[budwilson]

Thanks now it's starting to make a little more sense. Every time you go over a bump or drop into a pot hole the angle changes but not enough hurt anything. When the snow gets off I will have to crawl under and take a look at it. Thanks for making it a little clearer.

[Dunrollin]

Originally Posted by wolfe10

Dean,

I would still suggest that virtually all owners could do a quick inspection before resorting to towing.

Something as simple as the link coming off the ride height valve could cause this and could likely be "fixed" with no or very common tools.

YES, make sure you have "safe room" under coach so you will not be crushed even if air suspension completely deflated.

That was my situation driving down the interstate, air alarm sounded, the ride was unbearable. Fortunately I was at an exit, got off and took a trip under the motorhome. Heard a loud hissing at the back and found the pressure relief valve on the air dryer had tripped and was wasting all the air. Hit it carefully with my wrench and it reset giving me plenty of time to get where I was going. Shortly after I returned home I replaced the air dryer unit but I did avoid a tow.

[richard5933]

Originally Posted by deandec

OP here.

It appears that those of us, who are the average "DP with Air Springs" operator, will be calling the tow truck when a spring completely fails enroute.

Thanks to all who responded.

Always a respectable plan.

However, if you have a coach with a difficult-to-find air bag or with airbags which have a few years on them, it might be wise to carry a spare for each size. You'll likely have no trouble finding the tow truck to pull you to safety. If you have a difficult-to-find airbag though, you might be camping in their lot for a few days or more till one can be located. The older your coach gets the more spares you should consider carrying.

As an alternative, if you have a friend or family member able to ship things to you, you can leave your spares at home and just call for them as needed. Might involve a couple of days of waiting, but still better than a longer wait if your particular parts or generally NLA (no longer available).

[FIRE UP]

Well boys and girls,
*Hopefully*, we won't be experiencing any *Blown* or even leaking air bags in the near or, even distant future. I just finished replacing all four of mine, to the tune of $890 and that's with my 68 y.o. fat body doing the work. To those that think replacing them is an easy task or *roadside* work, well, you are definitely better men than I am. I did it in a controlled environment, jacks (both coach and bottle) were used, along with tire dollies, torque multipliers, 4' long 100-600 ft. torque wrench, and a roll-away tool box full of just what I needed to do the job, AT HOME.

Would or could I do it out on the road? Well, I gotta tell ya, if you've not done the replacement, either on front or rear, depending on your particular coach and it's age and layout, that can be one serious son of a ..... job. As an example, there are four large 1 1/8" nuts, that need to be removed to get components apart that retain the front bags on our coach. It took right at 500 ft. lbs. of my 4' long 3/4" drive torque wrench, just to break those loose. I do not, and never will, carry that 4' long 3/4" drive torque wrench in our coach.

And that operation was/is AFTER you've broke loose, (10) 450 ft. lb. lug nuts and, removed the 156 lb. alloy tire and wheel.

So, needless to say, without a doubt, I wouldn't EVER want to even THINK about tackling replacing especially the fronts on the road, or in a campsite etc. The rears, well, still a pain in the a... but, a tad bit more doable if away from home.

Each of us has our abilities, tools, knowledge and experience. What we're all willing take on, in terms of a repair, while traveling, most likely would be determined at that time.
Scott

[Submustang]

I actually had it happen. Tripped a circuit breaker that controlled dump valve. I tried to drive it thinking it would inflate once I had it in gear. WRONG. When I realized it was not going to inflate, I tried to turn around to take it back where I started. I hit a bit larger than normal bump in the process and broke the windshield, even knocking a corner of it out of the frame. I was going very slowly the whole time. Not one of my better decisions. Based on my experience, I would not ever drive it again without functioning air suspension. Not sure wood blocks propping it up would necessarily be any better, no suspension is no suspension.

[CountryFit]

This thread had the discussions on the very topic click here.

My post #12 still stands. Unfortunately the screen shot showing my manual content on post #15 was carried away by the deceased tinypic.com.

Though CC said ok to drive the coach slowly, now I am not sure... If the airbag is ruptured, air would escape from the bad bag, the air brake could lock up the axle, and the coach becomes immobile... Ouch!

[Dunrollin]

Originally Posted by CountryFit

This thread had the discussions on the very topic click here.

Though CC said ok to drive the coach slowly, now I am not sure... If the airbag is ruptured, air would escape from the bad bag, the air brake could lock up the axle, and the coach becomes immobile... Ouch!

As FIRE UP said above, even a short trip without a working suspension is dangerous, the brakes should still work even with a ruptured bag. There is a valve that shuts air off to all components except the brakes so stopping is possible but of course at that point you are not road worthy in my opinion. Your low air alarm will be blaring of course.

My quarter of a mile without air bags was enough for me, and with my navigator certain we could not be on the road in that condition I was stopped for sure.

[FL420]

Originally Posted by chuckftboy

On my coach if I lost the front air bags, I could only travel in a straight line. Turning without being aired up would eat up a lot of fiberglass.

I learned the truth of this the hard way. Traveling at night on a rough country road into town the ride suddenly got even rougher. I was in fairly heavy traffic on a 2 lane with no shoulders so my first opportunity to pull over to investigate was a Walmart parking lot several miles and a few turns ahead.
There were no problems with stopping or turning on the streets if I stayed off the stops but the very last turn in the WM parking lot required a tight 90° left turn and the front tire bit into the fiberglass of the left front wheel well surround.
When I got under the coach I discovered the U bolt that held the travel height valve connecting rod to the front I beam had broken dumping all the air from the 4 front air bags. Close inspection revealed the previous owner had worn the U bolt about halfway through by dragging it on something, probably more than once. I had seen the U bolt several times before but had not looked at it from an angle directly below to be able to see the wear.

[CountryFit]

Originally Posted by Dunrollin

There is a valve that shuts air off to all components except the brakes....

This valve is new to me, glad one more thing to be added to my knowledge base... Is this valve to be shut off manually or it's done automatically? Where is it?

[Dunrollin]

Originally Posted by CountryFit

This valve is new to me, glad one more thing to be added to my knowledge base... Is this valve to be shut off manually or it's done automatically? Where is it?

The location can vary but I think it is near the air tanks. Below a set pressure (60 to 75 psi) it shuts off air to all but the brakes. it is called a pressure protecton valve and is one component that has no wires, only air lines. One piece good news is they are relatively cheap and usually available. See this generic air schematic where I added a red circle.

[CountryFit]

Originally Posted by Dunrollin

The location can vary but I think it is near the air tanks. Below a set pressure (60 to 75 psi) it shuts off air to all but the brakes. it is called a pressure protecton valve and is one component that has no wires, only air lines. One piece good news is they are relatively cheap and usually available. See this generic air schematic where I added a red circle.

That's nice to know, sure enough it's there to reserve the pressure for the brakes . Learning new things every day .

[Barneyb]

Originally Posted by jacwjames

A post like this is why I surf the IRV2 site. Always picking up ideas about ways to improvise repairs to make to a service facility. I'm pretty mechanically inclined but reading posts like this gives me options.

I agree, great post