MCI Airbag replacement.....

[Ncbob]

I'm about to take on the job of replacing both my L Rear airbags in my MC5A this coming winter in FL and am like a dog $hitting peach pits over it.  Any advice would be more than welcome.

It strikes me that if I were to put some solid hardwood blocks between the air beam and the lower support that I'd be way ahead of the game for starters. I won't be doing this on a concrete slab so there's room for some help.

Before I open my mouth and convince you that I have no idea about what I'm about to embark on..I'll tell you up front...I know nothing!  But your advice would be more than welcome. I know that determination alone won't cut it.

Bob

[gomer]

first don-t panic about doing it.  second- air the coach up like you were going to ride and while it is up in the air, block up the coach SOLID because when you dont have the air bags up they will come down and it will hurt    I always put good cribs and build them and and secure the coach solid and then slightly jack the axle and remove the tires. it will be much more accesable to get to the bolts and remove them and slid the bag out{ no not the wife] and clean the area and re=install the new ones.  watch for rusty areas that might not let the new bag seat.  I think that ought to do er

[captain ron]

Hey Gomer, Didja lern all that at Cooter's Garage?

[gomer]

  no Iearned that by me one self haha

[captain ron]

Well gauhleee, Sing us a song 

[JackConrad]

I found the hardest part was getting the old bolts out.  Rusted and no head  (have a head kinda like a carriage bolt).  I used a 4 1/2" cut-off wheel and torch to remove the bolts.  Jack

[jjrbus]

Relax Bob its not that bad a job, for a thirty year old.  When you order the bellows, also order new rings and bolts. Now that you have ordered the bellows rings and bolts, you would think they would send you the nuts and lock washers also, right? Wrong, unless you want to make a trip to the store also order the nuts and lockwashers.
Many people have reused the old rings, for the few bucks they cost I would not want to redo the job.
A 4 1/2 inch angle grinder works very well for getting the old bolts off. Do not bother trying to save the old bolts it is not worth the effort.
                        HTH Jim

[JackConrad]

Bob,
   Ya'll are welcome to bring your bus to my shop to do this job.  I will be glad to give you a hand if you need it.  Jack

[Stan]

Flames and sparks under a bus can create a very dangerous situation. Air bag bolts are easy to remove if you spray them first with one of the penetrating sprays and then running a die nut down on the exposed threads. Any tool house will have 5/16"x24 die nuts. Note that this is not a threading die which is too large. A die nut is the same size as the regular nut (1/2") and is used to clean up threads.

The little dimples on the bolt head that lock the bolt into the ring and keep it from turning for the first couple of turns. After that the nut can be removed with your fingers or very little torque with a wrench while holding the head in place. Do not allow the head to rotate and destroy the retainers. If necessary put a pair of needle nose Vise Grips on to hold the bolt head tight in the ring.

If not working on concrete, make sure that you have adequate support under the axle before removing the wheels. A hardwood block between the airbeam and lower bag frame is a good safety measure but you may want to raise the body higher than normal to get the new bags in with less swearing. The new rubber is a lot stiffer than than the ones you take out.

I have seen comments on other threads that some new bags require longer bolts so it may be wise to just order the complete assembly. MCI used to sell individual components or there was a part number for the complete assembly that had everything in a plastic bag.

[captain ron]

Flames and sparks under a bus can create a very dangerous situation.

Breathing the air is dangerous but we've been doing it for years same as grinding and torching under a bus. I believe in safety but don't try to scare people away from doing what's necessary and making a job simpler and is of no more of a threat than farting in the same room with a wood burner. Use common sense when using any tool and there all safe.

[jjrbus]

 Those are 35 year old nuts and bolts, the guy going after them is double that. Its a few minutes with an angle grinder or 2 hours with a wrench and then may or may not get them all off. Damn the sparks full speed ahead!!!
Bob are your beams plated? maybe its time for rolling lobes?

[Hartley]

Be prepared to pull the tires off the rear.
Some handy things are: Die grinder, Air chisel, Cutting torch or plasma cutter
and plenty of band-aids.

You should get the new bolts, washers, nuts and rings to go with the new bags.

Don't even imagine that you can reuse the old ones. Way too much aggravation.
Just make sure the new bolts are long enough "before" you start taking the old ones off. This will save you a few headaches....

While you are under there you may want to check and replace the leveling valves so that you won't have to go back later to do that...

Sorry, I know the MC5 is different than the MC9 but the essentials are the same.

Dave....

[oldmansax]

Bob,

Make sure to order the block off plates when your order the bags,bolts, nuts, lock washers, and rings, assuming your bus has the air beams blocked off. I did not order plates and ended up doing the job twice.  No fun!

If your air beams are OK then you can ignore this advice until later.

TOM

[Ncbob]

Well guys, I feel more comfortable about it now. If I knew where I could find the ambition to chew this one off I'd go for a double order.  I have the grinder will need to stock up on some cutting wheels.  I'll round up some 12" timbers from one of the timber frame outfits before I leave here to block the weight off the rears.

Jack, old friend, I'd guess you're in the mix but not until after Arcadia. Thanks you for the offer...we'll work out the details.

I've asked Fred to order the bags for me and will correct my request to include the seals (rings) and bolts and nuts...lockwashers I've got.

Jim, you sound soo experienced...you might wish to drive up and lend a hand.

Thanks to all who offered their advice...when the time comes we'll keep you posted on progress.

Bob

[FloridaCliff]

Now Bob,

You know that I will ALWAYS give you a hand,
thats what neighbors are for.

I would much rather do it on the concrete floor in front of my shop though.

But, I bet you will get much quicker service from Jack(semi retired) than Me (still working). 

Cliff