Author Topic: Air Suspension system  (Read 403 times)

Offline DominicM

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Air Suspension system
« on: July 17, 2018, 08:23:08 PM »
Im sure I know the answer but I am still going to ask the question.  I aired up the suspension this morning via my electric compressor.  I left for a couple hours, when I came back I noticed that the drivers side front corner was lower that the rest of the bus.  I did fill it up again and climbed under enough to see both bag are filling up. 

At this point I will need to climb under and start checking for leaks with a soap and water mixture.    Reading the service manual there is a check valve, and a leveler valve. Are these generic parts that I can pick up at Fleet Pride or are they something that I need to preorder from MCI?  Is there any thing that I need to watch out for or be aware of before I start looking for leaks, check valves, and lever valves? 

I do plan on ordering new airbags from MCI and replacing all of them just as a preventive measure, possibly installing one of the kits to use the bags to level when parked.
67 MCI 5A
I live in Nashville,  and Reside in my 5A in Big Spring TX for work at the moment,  Will update as I move around.

Offline chessie4905

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Re: Air Suspension system
« Reply #1 on: July 18, 2018, 03:28:15 AM »
If bubble check doesn't give results, rig up a Schrader valve adapter to bypass levelling valve. This way you are directly airing up air bag. Check after sitting overnight. Worked for me a couple years ago to find a leaking bag. Good adapter to have around for finding elusive leaks. Don't go over 50 to 75 lbs.
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Offline richard5933

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Re: Air Suspension system
« Reply #2 on: July 18, 2018, 04:54:10 AM »
Just be absolutely certain that you block up the body of the bus before getting under it. If something gives way while you're under, there is not enough room to live.
Richard
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Offline DominicM

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Re: Air Suspension system
« Reply #3 on: July 18, 2018, 05:36:12 AM »
I have a dozen pipeline skid 4X6 blocks to use as blocks.
67 MCI 5A
I live in Nashville,  and Reside in my 5A in Big Spring TX for work at the moment,  Will update as I move around.

Offline bigred

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Re: Air Suspension system
« Reply #4 on: July 18, 2018, 06:56:04 AM »
Since your front suspension only has one leveling valve?? It would have to almost be a problem around the wheel ,however ,on my Preavy there are four leveling valves in the rear ,so I would also check to make sure it is not a problem in the back .Have a friend who has worked on a lot of fleet buses and he says the only difference in the leveling valves that you buy from MCI or Prevost and the ones you buy from Grainger  is the price .He tells me that he has even rebuilt these things .Hey guy's ,if I am telling him wrong ,some body slap my wrist again,lol 
« Last Edit: July 18, 2018, 05:31:21 PM by bigred »
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Offline Dave5Cs

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Re: Air Suspension system
« Reply #5 on: July 18, 2018, 02:39:59 PM »
Here is the could be's. Front
Blown Air bag you have 4 in the front.
Airbag filter on one side could be plugged up.
Disconnected air line from an airbag but will generally hear it.

Being it is like a triangle with 3 leveling valves, 1 up front and two in the back. Front adjusts coach level front to back and the rear leveling valves adjust side to side sooooo,
Bad leveling valve rear one side.
Stuck arm on leveling valve or broken arm.
"PATHFINDER"1979 MCI MC5Cs 6V-71,644MT Allison.
 1998 Jeep TJ & 2002 Buick Century, Roseville,CA
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Offline DominicM

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Re: Air Suspension system
« Reply #6 on: July 18, 2018, 03:07:29 PM »
Thank you for the insight, I will at the moment guess its one of the sides probably drivers sense the drivers side is empty in about an hour of standing still. I  can not locate any air leaks but all the bags are cracked so I will replace all of them. Sense I am already there I will replace the filters and levelers.  I did notice that the bung on the rear tank is covered in pack rust. I am afraid to touch it until I have a replacement tank.   Any ideas on where to get one at?

67 MCI 5A
I live in Nashville,  and Reside in my 5A in Big Spring TX for work at the moment,  Will update as I move around.

Offline chessie4905

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Re: Air Suspension system
« Reply #7 on: July 18, 2018, 07:27:48 PM »
Check with Luke at US Coach.
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Offline DominicM

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Re: Air Suspension system
« Reply #8 on: July 19, 2018, 05:15:47 AM »
he was on my list of places/ people to check with.
67 MCI 5A
I live in Nashville,  and Reside in my 5A in Big Spring TX for work at the moment,  Will update as I move around.