New Airbags - New plates?

[eb99603]

For any of you out there that have airbags that are literally just the bag when purchased new, do you ever replace the lower piston or upper mounting plate as well? A friend's bus has bags that, when ordered, come with upper/lower mounting plates attached to the bags (from the factory). My style isn't like that at all.

My piston, bag, and plate are 3 separate parts. Today I began the process of removing all of the bags for replacement as some appear to have been dry rotting for years. 

The upper plates seem to be in rough shape. Almost all have a layer of flakey rust where the top plate meets the bus frame. In some cases, nearly 1/8" thick. Now, that's 1/8" of bubbled/flakey rust not actually 1/8" worth of the top plate missing. The top plate dimples in maybe 1/16" or less.

I took a few pictures and will post those as soon as I can. Question of the hour - Do I drop $130/plate for new ones? Or are they good enough until the next time I replace bags? Have any of you run into this before, and what'd you do? If I need to drop $1k on new plates I will, but the prospect seems less than ideal.

[eb99603]

Some dry rot:


Some of what I'm dealing with

[eb99603]

Scary!

[Dave5Cs]

Could you use those for patterns and cut your own plates out of Aluminum or steel. Should be able to that for a lot less than the price of new ones.. Just saying.
Dave5Cs

[jackhanow]

how thick are those plate and are the beads in good shape. The rust on the cone is normal. They are just like a tire on a rim. I did a set of those as a roadside emergency. The driver drove the good side up on a block. I popped it off and just kinda set it in there pushed the bottom on the bead alittle and got the top to seat pretty easy and it filled right up. Gotta watch your fingers. Cause once they start inflating, it goes pretty fast. The driver told me the trick. How much of that is frame?  From what I see I don't think your gonna notice the difference between those plates and new ones. Paint them and check them next time. By the way don't  use soap or other lubes on the beads to install.  

[chessie4905]

My sitting g P8M4905 has the three piece air bag setup like yours. Mohawk Bus Parts sell a bag that eliminates the extra parts. Apparently an upgrade years ago to save labor for the bus companies.

[eb99603]

Hey guys, thanks for the responses. The plates actually don't look too bad when cleaned up. Some worse than others, but there's still a good bit of metal even in the thinnest spots. The rust is worst on the top of the plates. The bottom is generally in goodish shape and most importantly the beads are all great. I decided to just go for it today.

Chessie, I don't care what those cost, when it's time to replace these bags again, I'm calling Mohawk. This three piece aparatus is a PITA to install. It takes all of my strength to get the bag seated on the piston, and then rolled down the side. All the while hoping I rolled it just far enough so I can smash it into the space in the bus, and not have to try to "unroll" the bag while underneath the bus. It's exhausting work. Perhaps it'd have been easier if I took the wheels off, but {shrug} it didn't seem necessary at the time.

Work in progress:


Don't mind the bump stop. (It came out like that - not my doing.)


Had to spend some time melting nylon today to salvage two of these sleeves. No one in town had anything of adequate thickness.


A bit more of a gap than I'm comfortable with, though the gap's almost entirely created by the frame mount, not the bag plate.


A little better looking on the rear drive axle bag. Again, the frame mount has a bit of a bend to it.


Anyway, they're all in and leak free. Woohoo.

4 old bags against 2 new. All the same style.

[bigred]

Was that big gash in that air bag or did you do that getting it out?If that bag was that way before you removed it ,I don't see how you were getting enough lift to clear the tires!!