| Author | Message | ||
| Jim Connelly (Desertbum)
Registered Member Username: Desertbum Post Number: 11 Registered: 2-2005 Posted From: 207.200.116.13 Rating: N/A |
Can someone tell me if the suspension air bags on a 4106 are all the same and if this is something better left to a pro to change? There are two in each rear wheel area. Is it best to change them in pairs or as they leak. They might both be leaking on the left rear as I can hear a loud air leak and it is low in the left side. Also please, is this an air bag that could be purchased at a local truck parts store or do I need to order it special? I have my 4106 at home so no problem there. I am a good mechanic but the size and weight does intimidate me as far as getting under it. Thanks for any comments, Jim 4106 in SoCal | ||
| Don Evans (Doninwa)
Registered Member Username: Doninwa Post Number: 286 Registered: 1-2007 Posted From: 208.81.157.234  Rating: |
Before you do I would nail down where the air is coming from. Might be something other than the bellows (air bag). I would order them from Luke a US Coach. Super nice guy and super supporter of the bus community. He even had the foresight to include the special nut need for the stud that the air line fits. They come completely assembled so ignore DA Book about changing the end plates. Just did one for a fellow busnut. Not that bad if there is just a little bit of contortionist in you. It is all covered in DA Book. Following is what I remember but I defer to DA Book, as I was also changing the lower mount frame. Basically, SAFELY block (should read crib) up the body by DA Book. Since you are taking the rear axle (parking brakes) off the ground you MUST securely block the bus so it can not roll. Put a floor jack under the axle. Remove the wheels. I would do one side at a time, just me. Unbolt the leveling valve and push valve, up I think, to deflate bellows. There is a delay built in so hold it there for a while. Remove 4 bolts from top plate (slight contortionist here especially on right rear bellows because of hoses in the way) and 2 bolts from bottom holding bellows in place. Love those fine thread bolts with lock nuts! :>) This lets the bellows down a bit so you can remove the air line from the top of old bellows. Do a little bit of rust removal and you are ready to install new one/s in reverse order. Good luck Don 4107 | ||
| Jack Fids (Jack_fids)
Registered Member Username: Jack_fids Post Number: 184 Registered: 1-2009 Posted From: 69.171.161.220  Rating: N/A |
Based on my very recent experience doing a front bag replacement..... Don has just given the most succinct spot-on instruction one could hope to have prior to performing the job. The only addition I can possibly add is: the brass fitting on the top plate for the air line to bag connection is slightly different. STOCK was a rubber compression fitting which had a deeper well to receive the hard line. Luke supplies a BRASS BALL compression fitting, slighty shalloer well for the hard line. The important issue is ...IF the hard air line is corroded near the fitting end the brass ball will not fir over it. If it looks "thick", a bit of sandpaper in a strip shoeshine style will go a long way towards having to replace the whole line. Be VERY careful removing & replacing the original brass & you won't run the risk of having one strike against you when you're in the tight place. Everything else is straight forward common sense, a little patience, strength & finesse you can pull this off in a short day with ease. The pieces are big but the job is small potatoes, don't be fooled or daunted, just use you head & some good tire chocks. I weigh 125#'s, can't remember this morning and have the minimum of half inch sockets & ratchets & I finished a single bag in 5 hours with the wheel on with no jack & only 11-inches of clearance to squirm in... (contortionist-ism runs in the family). It's not a job worth losing sleep over that's for sure! | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1339 Registered: 10-2006 Posted From: 99.173.23.73  Rating: N/A |
Squirt a bit of water / soap at the bags and especially at the leveling valve. It may not be the bags. FF | ||
| Jim Connelly (Desertbum)
Registered Member Username: Desertbum Post Number: 12 Registered: 2-2005 Posted From: 207.200.116.13 Rating: N/A |
Hey...Thanks for the info and advice. I feel better about crawling under there and also, I will make sure it is the bag.I have the safety stuff to secure it all. Thanks again, Desertbum.SoCal | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1988 Registered: 10-2003 Posted From: 71.58.71.157  Rating: N/A |
When I had a pesky leak, I made a schrader adapter and disconnected line to suspect bag. (relieve air via, leveling valve first after proper blocking? Attach adapter to line and pressurize. It. will then show whether the leak is in the bag/air beam (on 4104's), or the other components in the system. Keep the adapter in tool box for future diagnostics | ||
| Jim Connelly (Desertbum)
Registered Member Username: Desertbum Post Number: 13 Registered: 2-2005 Posted From: 207.200.116.13  Rating: |
Follow up..Good news. I was able to find my leak and it was a rear bag. I drove it up on some wood blocks and was able to slide under and get to the bag. I replaced it. I had a spare bag with some of the parts I got when I bought the bus and it happened to be a rear so I was able to use it. Like you guys said, it was not too bad of a job once you get to it safely.I followed the instructions you gave me and it took a little time but it is done.I found an air line going to the brakes leaking while I was there and I replaced that line. It was rotted.Napa had one that worked out. I had to change the end fittings. Thanks for the help, Jim 4106 SoCal |
