Author Topic: Air Ride Question  (Read 427 times)

Offline Rcurtin

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Air Ride Question
« on: September 14, 2019, 09:35:28 PM »
Hey all just had a quick question with something I am learning more about every day but still not all that familiar with. My bus (1989 Flxible Metro 40102 6C) has an issue with its air ride system. After sitting for a while the entire left side of the bus lowers causing it to slant. While the bus is running there are no issues and I have no audible air leaks. Weather permitting I will be getting under her and spraying some soapy water to find any smaller leaks soon. My question, is there a way to "release" the other side while I am not running the bus? I am on shore power and connected to sewer and water at a park so I do not need to run the bus. I have only owned this rig for a couple months and haven't had much time to fully get to know her inner workings fully. From what I can tell there are 3 air tanks 1 is very large and assuming this is the main air system. There are 2 smaller tanks one on each side near the front wheels. Can I release the air from the right side to "even" the rig out manually?

Thank you in advance

Offline buswarrior

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Re: Air Ride Question
« Reply #1 on: September 15, 2019, 02:47:16 AM »
Focus your efforts on the rear air bags and leveling valve on the side that drops.

Levelling valves lead a hard life and get leaky, out the exhaust, out the shaft attached to the linkage. They move all the time when the bus body moves, so they are a wear item.

Safety first, please don't go under the bus until you know how to block it so you stay alive

Search function on here leads to lots of reading.

Happy coaching!
Frozen North, Greater Toronto Area

Offline chessie4905

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Re: Air Ride Question
« Reply #2 on: September 15, 2019, 06:05:45 AM »
You could, also after proper blocking, disconnect line going to airbag from leveling valve. Make up an adapter made up of a Schrader valve (tire inflation stem) and necessary adapter to connect to bag air line. Inflate to no more than say,80 psi. Check your adapter with soapy solution for any leaking and correct as necessary. Check the next day or sooner if faster leak. If it checks ok, check opposite side while you are at it if you desire. With everything connected, you can check the rest of system, either before or after. I found a leaking bag on my 4905 with this.|71700000053806316|58700005143166037|92700045172697044&gclsrc=aw.ds&&gclid=EAIaIQobChMIy_CRsvLS5AIVjh-tBh3XGAt7EAQYASABEgJQqvD_BwE
GMC h8h 649#028 (4905)

Offline rgrauto

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Re: Air Ride Question
« Reply #3 on: September 15, 2019, 07:52:52 AM »
My bus would sag on one side after a few days and my solution was to build a set of blocks,one for each side where I always park. Build with bus fully aired up leaving blocks two inches ,give or take , below suspension,body,a strong place ,not axle add wheel stops so bus will stop in same place every time,problem solved. Bus needs to be fully aired up before you drive off or you will hang your blocks.

Offline richard5933

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Re: Air Ride Question
« Reply #4 on: September 15, 2019, 07:54:34 AM »
When our 4106 did that the culprit was a rear valve leaking internally. Air was getting past the check valve and going back to the tank. No external leaks were found.
1974 GMC P8M4108a-125 (Custom Coach "Land Cruiser")
1964 GM PD4106-2412 (Former Bus)
Located in beautiful Wisconsin