Driving with a failed airbag/airbeam

[Tenor]

I'm in a pickle and need advice.  My MCI 7 blew a drive axle airbag, which is keeping the passenger side from airing up.  It still has the airbeam system.  The bags are not plated.  Can I drive this thing as far as 20 miles to get it to a shop or do I need to fix it where it is?  I at least am on pavement in front of my parents house and have acess to most tools.  Thanks!

Glenn

[Christyhicks]

OK, I'm not sure why my post ended up on this thread, so please just ignore it, ok?  We'll blame it on the ever-present Gremlins!   Christy Hicks

Christy,
    I went ahead and delated the post, but will leave all the comments about your mistake!   LOL   Jack

[lostagain]

How big is the hole in the bag? If the compressor can keep up, drive it to the shop. I would think in most cases, you could drive it a few miles to a shop. If not, changing an air bag isn't that big a deal if you have good tools to remove the old bolts: a saws-all or a torch.

JC

[kyle4501]

An old, really old, really really old, former Hound mechanic said that back in the day, late 50's thru the 70's, they would jack it up, shove a block of wood in there, block off the air & drive 'em in to the shop for repairs. 

I don't know that I'd do it if I had other choices . . . .

Christy, It looks like the men aren't the only ones that aren't paying attention.     

[Christyhicks]

Christy, It looks like the men aren't the only ones that aren't paying attention.     

HAHAHAHA

Well, I do have a defense this time, it's the "It's Monday 'cause I bonked my head on the music stand while exercising this morning". . . , but that, too, was another story that definitely doesn't belong in this thread, or,  ;)well, in any other, ha ha.  Christy Hicks

[Tenor]

JC, the hole is about an inch in diameter.  Big enough that it did not hiss, it just dumps air.  I did drive it around the block, in thoughts that it might be a bad leveling valve, but after putting it up on ramps, the hole became obvious.  It also explained why my Dad and neighbor heard a big bang...

Kyle, I have access to a sawsall.  I have changed airbags on GMC's but not on an MCI.  What is the best way to use the sawsall - on the bottom and just hack through the retainer rings and bolts, or from the top?  

Anyone ever use the "Really old Hound Mechanic" approach?

Thanks!

[kyle4501]

. . . . What is the best way to use the sawsall

Very carefully. 

If it were me, I'd fix it where it is. You have to fix it anyway & you aren't on the side of the road . . . .

My limited experience would have me buying all new bolts, rings & bag & just 'get after it'. I used a razor to get the old bag out of the way & lots of imagination to remove the bolts.

[jjrbus]

To me the tool of choice was a 4 1/2 inch angle grinder with cutting blades, not grinding blades. All the old parts were out in minutes. If you go after the ring side there is a small chance you could damage the seating area of the bag. I vote for the nut side!!  HTH Jim

[gus]

When I removed the bag bolts on my 4104 the bolts with seized nuts just broke off. Maybe your bolts are larger, I think mine were 5/16".

If you drive it with such a large hole the hole might suddenly enlarge so much you no longer will have brake air pressure. If you have spring brakes you will come to a sudden stop!

[fe2_o3]

Yes I've used the out hound mechanics trick. Ran about a dozen blocks with wooden blocks tied to the lower beam, in front and behind the axle. Bumpy ride but, slowly, it got the coach to the shop. Location and traffic required this, but it is not my first choice. If you have a place to safely do it there. Save your kidneys. Do it there...Cable

[Tenor]

Thanks everyone!  I'll call Mohawk in a little while and get a bag/rings and bolts overnighted and just do it on the road.  At least it's a 25mph side street!

Glenn

[HighTechRedneck]

Thanks everyone!  I'll call Mohawk in a little while and get a bag/rings and bolts overnighted and just do it on the road.  At least it's a 25mph side street!

Glenn

Are there any parking lots close enough you could carefully limp it over to?  That would be better than working on it in the street.

[JackConrad]

   If it is the front bag on the drivers side, the bolts towards the front of the bus are the most difficult to get at. I used a 4 1/2" grinder with a cut-off wheel. Depending on bolt location, some I cut the nut vertically with the blade running along side the bolt, then knock whats left of the nut off with a chisel. Others I cut horizontally right above the plate the air bag attaches to.  Jack

[buswarrior]

Try the fasteners first!  I was pleasantly surprised when I did a tag axle bag, they all  just loosened off and the rest of it needed the screw driver to pry off the mounting point.

The less I use cutting and hacking tools, the fewer BIG mistakes I make....!!!

If you were going to drive it, you just have to confirm that the pressure protection valve is doing its job and keeping the brake system isolated at the pre-determined minimum before allowing air to the suspension.

The air leaking out the bag stops shortly after engine shut down, and there's still decent air to make the brakes work after the leaking stops? It'll be working. Long lingering leak down, and no air to make the brakes work? It is nonfunctional, and you have something else to fix for the safety of your bus operation.

driving that distance won't do anything to the compressor that hasn't already been done to it by others.

happy coaching!
buswarrior

[Tenor]

Thanks again everyone!  Since I'm on a 25mph residential road with great police presence (the neighbors!) I borrowed some construcion barricades and have those out in the road, since I'm barked opposite the direction of traffic.  That gave me room to get the wheels off.  I've got about a third of the bolts for the bag off and only one has broken so far.  I have the bus nicely blocked up so that now I can get to the inside ones.  The new bag and rings and bolts will be here in the AM.  Wish me continued luck!

Glenn