My time in the barrel

[poppi]

Well I have been putting it off for 9 months now. Since the bus wasn't going anywhere I didn't worry about it.
Now I want to get it on the road again. So I traced down some air leaks. The airbags on the walking beam are
leaking. Tag and front are airing up fine. Well I'll need to replace the airbags so I can find the rest of the leaks.

So my questions are. (and I did search but with so any hits it would take me a week to find what I am looking for.

   1. Place to get the parts that does'nt require a prior account.
   2. A while ago I viewed a web sight where  the guy had a good picture documentary on changing airbags.
       anybody know a link?
   3. My beems seem to be ok maybe won't know until I get the bags replaced. Rolling lobes and just bypass the whole
      issue? thoughts appreciated.

   Probably will need new rubber stops also.
  Thanks for the input
   skip

[belfert]

I don't recall any bus/truck parts place that won't sell to cash customers including local places.  Heck, these days a lot of places will sell to anyone just to make a buck.

Try Mohawk, US Coach, or Muncie-Baker for your parts.

[jackhartjr]

Skip, are you sure it is the air bag itself leaking?
Jack

[skolbibp]

IBP can supply the block off plates and rest pads in polyurethane.  Call me at 1-800-468-5287 or email me at skolb@ibpindustries.com . 

Steve

[Chopper Scott]

I've came to the conclusion that I'm in it for the long haul and am going to covert over to the rolling lobes on my 7 regardless. I have already fixed a leak in one of the rear beams successfully (fixed it from the inside of the beam then patched over the hole in the beam I made to get to it) but figure it's just a matter of time. If I'm correct going with the rolling lobes you don't need the blockoff plates as the lobes have an exterior line supplying them. There are short and long fixes to every problem. I had to change the 65 lb regulator on the front axle that had a leak also. Lots of places for leaks!! Later

[Sojourner]

About the choice of which route should you spend your money for the longest life and the quickest fix.

First of all...your MCI may already have a block plate with an air line attached to the edge of the plate. Which mean it been installed to by pass leaking air-beam.

If no plate in-between double convolution air bag (spring) and the air beam and it is leaking from either bag or/both air beam. My suggestion is go for rolling-lobe type air spring.

Why?...Here are 4 good reasons:
1)   If air beam is leaking but not sure where and how many more future leaks after it repaired plus you may have to remove part of the flooring above the air beam (about 8" x 40" long) to get access to repair. Most lightly it on top of air beam that gets corroded from build up of road salts if it been in the cold climate area.
2)   Old air bag leaking badly around the ring of mounting bolts. You can retighten them but is could be flaky or hair-line cracked rubber sealing from old age.
3)   Rolling lobe is whole lot better cushioning than double-convolution spring. Example....using a toy balloon that is about 8" diameter lay on top of table. Take a drinking glass and push the base of glass down from the top of the balloon to learn how far it travels before it pop (it may not pop that ok). That is a Rolling-Lobe demonstration.  Now for Convolution demonstration is to have a balloon on table but compress with a large flat surface hard bound book down-ward till it pop. See for yourself which travels the most and push the easiest before it pop or bottom out?
4)   Parts cost is nearly the same.

The bottom-line is to maximize the ratio of cushioning as possible for the softest ride before the bottom-out.

BTW...a non-leaking air beam with double convolution (OEM) is about the same ride comforting as a rolling-bag set-up but without the air beam.

Sojourn for Christ, Gerald

Example of rolling-lobe conversion kit for MCI
Mohawk

[poppi]

Thanks for the input guys. I think I'll go the rolling lobe type

Jack:
   Fair enough question. Diagnostic methodologies can always be improved on. So I'll explain how I came to this point in
my mind.

   I try and use all my senses when trying to diagnose a problem but over the years some of my senses just aren't what they
used to be and are a constant question of the voracity of there input.

   Hearing: after 34 yrs of being around diesel engines and impact wrenches my hearing is to the point where I can here a leak
               but I have trouble pin pointing direction. I can here air behind the tires but couldn't be sure if it was a line, tank,
               valve, or wind blowing through my ears.
   Sight: I have always been myopic thus seeing problems has always been an issue for me. Soapy water would work if the
            tires weren't in the way and if I could get the bus high enough to drive it on blocks I could get under it to check the
            rest of the components. The bus tires have settled down in the ground more than I thought they would. I parked it
            where the prior owner parked his tractor. (must have been light ground pressure and not as compacted as thought)
   Taste: not applicable in this situation.
   Smell:  not applicable in this situation.
   Touch: Of my 10 fingers 8 work pretty good. 2 have nerve damage....long story But 80% is still pretty good so that is what
             I depended on. with a 63" inch spread I can reach in around the tire to feel for air leaking on the bags. 2 bags I can feel
             air around coming directly from the bag itself. the third the air changes pitch when I stick my finger in the fold.

   Thus I concluded 3 bad air bags. Might as well change the fourth while I am at it Last time I was under the bus I can't remember seeing any bumper stops but then again my memory is always suspect.

    If I have an error in my methodology please let me know I'm always up for improving myself.

   Thanks
   Skip

[jackhartjr]

Skip, when I asked the question I was not trying to be funny...if you took it that way.
In my experience with truck air bags they usually blow up...never just a small leak.  I wondered if the air may be coming from the mounts or air supply line.
Again...if you took it that I was challeging your mechanical expertice, that was not the case.
Jack

[JohnEd]

Skip,

As I share all of your current condition plus partial paralysis and blind in one eye, I got a very big laugh from your post.  Yeah, I use all my senses too.  Morals:1) misery loves company 2) First liar doesn't stand a chance.   As to your comment about your memory....I am referring to your last post   At least I think I am....can't say for sure at this point???

Jack,

Way to go!  This was a clean sweep for me.  Paranoids love company, too.   Nice of you to be concerned.....for me.  Oops, add ego centric, also.

Thank you both....sincerely

Poppi,

I use a stethoscope with a 12 inch length of copper tubing attached instead of the stock diaphragm.  It is like a directional mike and you can zero in on the sound you are looking for and follow it to its source.  Putting it right on the leak might be a solution to your hearing any darn thing at all.  Be careful.

John

[poppi]

 Jack,
   No umbrage taken at all......Though it doesn't stop me from having some self directed fun posting on
 something that is going to take some time and money to resolve. The bus isn't like a truck where I can lift up the
 back end a bit to R and R the bags. Yes air bags usually blow out. It could be at the mounts wouldn't rule it out.

 No matter what it requires jacking the thing up.   And if I am going through the trouble a little preventive measure isn't
out of the question. I have no records on the maintenance if this rig and I don't trust looks alone.

  I basically work 14/7 and my MCI fix or repair daily leaves little time for interior work. If I couldn't make light of the bus
issues then cliff driving would be high on the list of things to do.

 Still wish I could find that link of an air bag R&R....I want to see which jacks he was using.

  Thanks
Skip