Author Topic: Air bags not filling up  (Read 4287 times)

Offline Branderson

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Air bags not filling up
« on: March 25, 2019, 06:47:22 AM »
I started her up yesterday and the front bags are not filling up.  You can hear the air which I immediately knew something was wrong.  I don't think the air is even getting to the air bag but I have a mechanic coming to check it out hopefully today.

My question is if it's still drivable when the front bags are not up?  I didn't want to take a chance and ruin the fenders when turning b/c it looks like it could touch.  I figure it's best to have the mechanic come to me.
- Brad

Offline Jim Eh.

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Re: Air bags not filling up
« Reply #1 on: March 25, 2019, 07:27:16 AM »
About the only thing you should do is drive it up onto ramps at your location. You probably will damage fenders/air bags/possibly steering components.

You could jerry rig an air supply from the drivers seat directly to the height control but if you are going to go that far you may as well just fix the problem.
"Some days it's just not worth chewing through the restraints"
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Offline Dave5Cs

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Re: Air bags not filling up
« Reply #2 on: March 25, 2019, 07:38:50 AM »
Your air dryer s purge valve on the bottom of the long cylinder on the from wall of the front wheel well is probably open and leaking all the air out. If you can't air up in 90psi your brakes will still be locked. Try taking a stick and slap the bottom of the air dryer to see if it will close without going under it. You will need to service it because sound like it hasn't been done unless you live in cold country then it might be frozen and you can slide a small heater under it to thaw it out. :)
"Perfect Frequency"1979 MCI MC5Cs 6V-71,644MT Allison.
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Offline Branderson

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Re: Air bags not filling up
« Reply #3 on: March 25, 2019, 07:46:01 AM »
The mechanic is bringing ramps so he can get under there.  Thanks for the input.  My gut said not to drive it, I'm glad I didn't.

The PSI guage got to the normal setting and the rear was aired up just not the front.  Over the phone the mechanic thinks it might be a line that detached but he's not sure.

- Brad

Offline Dave5Cs

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Re: Air bags not filling up
« Reply #4 on: March 25, 2019, 07:54:28 AM »
If rear aired and the front didn't could also be a check valve between the accessory tank and the front leveling valves.
"Perfect Frequency"1979 MCI MC5Cs 6V-71,644MT Allison.
2001 Jeep Cherokee Sport 60th Anniversary edition.
1998 Jeep TJ ,(Gone)
 Somewhere in the USA fulltiming.

Offline Branderson

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Re: Air bags not filling up
« Reply #5 on: March 25, 2019, 12:05:03 PM »
Okay turns out the air line broke. Apparently it was plastic or a plastic part that broke so he's going to replace it with a copper line.  He pinched it off with a zip tie and it aired up properly and I will drive it to his place tomorrow. 
- Brad

Offline buswarrior

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Re: Air bags not filling up
« Reply #6 on: March 25, 2019, 12:12:06 PM »
Preventive maintenance opportunity...

Go find the rest of 'em and change 'em out.

In the shop on purpose, or on the road on your own...

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline Branderson

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Re: Air bags not filling up
« Reply #7 on: March 25, 2019, 12:14:02 PM »
That's a good point warrior.  We are going to Talladega for the races next month and I don't want any mishaps b/c there's not much out there and this will be my first dry camping with it.
- Brad

Offline Branderson

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Re: Air bags not filling up
« Reply #8 on: March 26, 2019, 06:00:33 PM »
Heres under and see where the line broke. It was only half broke but he cut it so he could zip tie it yesterday. He put in a copper line so hopefully that lasts.
- Brad

Offline Jim Eh.

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Re: Air bags not filling up
« Reply #9 on: March 26, 2019, 06:36:11 PM »
That line does not even looks like a DOT air line.
"Some days it's just not worth chewing through the restraints"
Jim Eh.
1996 MC12
6V92TA / HT741D
Winnipeg, MB.

Offline buswarrior

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Re: Air bags not filling up
« Reply #10 on: March 26, 2019, 06:39:52 PM »
No mater the type of piping, be sure it is protected from movement/vibration where it carves through the pylon, and anywhere else it could touch anything.

Vibration rubs holes in EVERYTHING...

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline chessie4905

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Re: Air bags not filling up
« Reply #11 on: March 27, 2019, 04:14:16 AM »
Is that line for the ice maker?lol If I were you, I'd check all the other lines for that material. It's not designed for that use.
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Offline richard5933

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Re: Air bags not filling up
« Reply #12 on: March 27, 2019, 04:41:47 AM »
And if replacing with copper air lines, be certain to use the correct type of copper tubing and brass fittings. The flare fittings from Lowes or Home Depot are NOT the same as air line fittings, and the copper line needs to have adequate wall thickness to withstand the vibration and pressure.

Most decent parts suppliers will have the correct air line fittings.
Richard
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Offline Gordie Allen

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Re: Air bags not filling up
« Reply #13 on: March 27, 2019, 12:30:50 PM »
Paradise fire victims we gave our bus to just called with same issue. Right front side won't fill. Air pressure 100# and they can't hear any leaks. They're in Redding. Any shop up there that could help? Also, could it be the leveler valve?
Augusta, MI
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Offline Branderson

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Re: Air bags not filling up
« Reply #14 on: March 27, 2019, 12:37:25 PM »
I think not hearing the leak is important b/c I could hear it big time.  I wonder if it's more of a check valve issue.
- Brad

 

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