Author Topic: Air bags not filling up  (Read 4271 times)

Offline buswarrior

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Re: Air bags not filling up
« Reply #15 on: March 27, 2019, 12:38:33 PM »
I've seen 'em simply be stuck, and a short bit of "agitation" by moving it and it springs up.

Sitting is the DEVIL for these worn out old whores.

Achieving some sort of normal pressure is half the battle, bent leveller arm, seized valve, ancient lube inside finally gone hard enough to block movement...

The only reason they go, is if they keep going. Park it on dirt for months at a time.... trouble.

It ain't yer Dad's Oldsmobile...

Happy coaching!
Buswarrior

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

Offline Gordie Allen

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Re: Air bags not filling up
« Reply #16 on: March 27, 2019, 01:08:14 PM »
My thinking is to (1) make sure the leveling valve is moving freely. (2) If that doesn't do anything try blowing out lines (100# should do that, but I guess a big gob of old hard crud could block it (3) or bad check valve.
Augusta, MI
1956 4104
DD 671

Offline chessie4905

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Re: Air bags not filling up
« Reply #17 on: March 27, 2019, 01:12:43 PM »
There is only one leveling valve on the front of the GM's. It controls both bags. Two at rear, one for each side. If right rear isn't filling, it can tilt front of coach, giving the inpression that there is an issue at the front.
GMC h8h 649#028 (4905)
Pennsylvania-central

Offline richard5933

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Re: Air bags not filling up
« Reply #18 on: March 27, 2019, 01:26:40 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?

From my understanding, if it is just one corner leveling valve not the first thing to look at. When I have had one corner not building air it was either a lose air line connection at that corner or a leaking bag.

The front leveling valve controls the front-to-rear height, so two corners would be down. The rear valves each control the height of the front & rear corners on that side, so again two corners would be down.
Richard
1974 GMC P8M4108a-125 Custom Coach "Land Cruiser" (Sold)
1964 GM PD4106-2412 (Former Bus)
1994 Airstream Excella 25-ft w/ 1999 Suburban 2500
Located in beautiful Wisconsin

Offline Gordie Allen

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Re: Air bags not filling up
« Reply #19 on: March 28, 2019, 12:49:41 PM »
So the problem has to be downstream from a check valve on the right front?
Augusta, MI
1956 4104
DD 671

Offline Gordie Allen

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Re: Air bags not filling up
« Reply #20 on: March 28, 2019, 01:01:28 PM »
So can a 4104 be towed without removing the drive shaft or releasing the brakes?
Augusta, MI
1956 4104
DD 671

Offline Dave5Cs

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Re: Air bags not filling up
« Reply #21 on: March 28, 2019, 01:16:06 PM »
Releasing the brakes and pulling the axles.
or removing the driveshaft.
"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.

 

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