bus not level when air up

bowmaga · April 17, 2008, 04:58:06 PM

We went and picked up our bus today, and noticed it seems the passenger side rides hirer than the drivers side. Is there any adjustment in the air bags that can be done...or is this a bigger problem? Its looks like one side is 3-4" higher than the other side.

FloridaCliff · April 17, 2008, 05:00:57 PM

The leveling valve may not be set right or disconnected

or one of the bags or hoses is leaking on that side.

Either way, block it up before going underneath.

Cliff

FloridaCliff · April 17, 2008, 05:03:41 PM

Drive it a little and see if it fixes itself first.

It may be just from sitting...

Cliff

PP · April 17, 2008, 05:20:18 PM

More than likely leveling arm on rear is bent or just out of adjustment, unless you can hear air whistling out. But like Cliff says, block it safely before you crawl under. Suddenly deflating bags can kill

Good luck with her, Will

Runcutter · April 17, 2008, 05:23:05 PM

Greg, I used to bring in dead buses periodically. This one could also be a disconnected/broken, or bent link between the leveling valve and the (axle? - I'm a GM guy). I remember bringing in a GMC transit by stopping every frequently, and hitting the link with a broomstick to air the bags back up.

You may be able to look in with a flashlight, and see if this is the issue.

Pay heed to the above, do not get any part of your body between hard objects (bus/tire, bus ground), without proper blocking.

(Edit - I guess Will and I both thought the same thing at the same time - too bad this isn't a place where we vote on the problem, because this would probably be the cheapest fix).

Arthur

bowmaga · April 17, 2008, 06:17:12 PM

the bus is on its way from Toledo to my house right now. I hope its something that is just disconnected. It drove an hour from Detroit to Toledo tonight and didn't level it self, so i think its more. It was just at the Allison dealership getting worked on so maybe something just got disconnected. I'll keep you posted. Should be here in about 30 minutes. Any exact place I should look first?

NJT5047 · April 17, 2008, 06:18:29 PM

May want to drive it a little before working on the leveling valves. Leveling valves suffer from lack of exercise (so do I

) and may begin to work correctly if driven a few miles. However, the low side drive axle leveling valve is very likely the source of your problem.
Could be other things too. Leaky anything on the low drive axle side...air beams, bags, bad leveling valve (s), or bent linkage. Keep in mind that the drive axle leveling valves are the side-to-side leveling.
One other item to check is that the tag axle dump valves are set correctly. Reach around the tag wheels and check the bags for inflation. If one dump valve is open, the bus may 'list' to the side with the uninflated tag bag. The valves are inside the RH side engine service door.
Air it up, shut it down (or use shop air), and get your wife to listen for leaks. Children can hear really well too. They'll hear things leaking that most adult males cannot hear.
If the air compressor is cycling frequently...on the highway maybe more than every 15 minutes, and the air leaks off the bus within minutes, some of the leaks should be repaired.
Get an MC9 manual so that you can sort out jacking up the bus and leveling valve adjustment.
Good luck, JR

TomC · April 18, 2008, 07:13:12 AM

My right rear valve is sticky in the morning. The bus leans to the right, but with the manual leveling controls I have, I can just level it up. Once the valve warms up, don't have any problems the rest of the day. Probably should replace all the valves. Good Luck, TomC

bowmaga · April 18, 2008, 10:50:07 AM

Yea, the bus has a serious lean to the left. My tag axles won't drop down, would that have any cause in it? I feel i might have bitten off more than i can shew with this bus. If anyone is in the Northwest Ohio area and wants to stop in and teach me everything they know, i would love it. June race at MIS is in about 58 days and i don"t think i will be ready for it. Starting to panic. I have my maintenance manual, and I'm pretty overwhelmed. If I can figure out this lean problem and get the tag axles to drop I would feel a lot better.

zubzub · April 18, 2008, 11:16:20 AM

Dude, I have nothing to add re the air bags, others are covering that. Re "starting to panic" well I've been there. These bus things are huge, and everything takes twice (3X? 4X? 5X?) as long than on a car. Jeez the other day using a air line from a big garage just bringing my tires up from around 35psi to 90 took close to 30 mins...5 of those sitting on my @$# after I almost knocked myself out smacking my head into the mirror arm. And filling up with coolant who knew that actually took a chunk of time. But driving that big ol beast around was great, and while the learning curve is steep, if you do good work along the way, many of the systems should not require constant maintenance. Well anyway, I've noticed thinking you bit too much off is a common feeling among the beginning bus nut crowd. Good Luck, Patrick.

bowmaga · April 18, 2008, 12:24:38 PM

my bus has been sitting all night now, and its still sitting leaning to the drivers side....shouldn't the air have settled out and basically deflated the bags to nothing and it should be level now? how do i deflate the bags on the passemgers side to set the bus low to the ground? or should i not do this or can't i do this? How do i adjust the leveling valves? help...help..help..

hiwaycallin · April 18, 2008, 01:28:42 PM

I think the fact that it is still aired up after sitting overnight is a good sign (no air leaks). At least that's one thing you've got going for you.

FloridaCliff · April 18, 2008, 01:45:05 PM

Greg,

Do you have the Maintenance Manual?

If not you reallly need one or someone on here may be able to fax you the pages you need.

Or someone with the same model may be able to talk you through this on the phone.....

By the way, you want it to stay aired up...its a good thing.

Cliff

bowmaga · April 18, 2008, 02:15:03 PM

i have the manual on cd in PDF version...looking at it made me feel even worse...ha. I shows me where stuff is....but what do i do with it? I know where the leveling vals are....but what do i do to try to fix my issues? To me it seems like the drivers side just isn't getting air but the passengers side is. Is there something I can start to look to resove with that. What is the first thing i should do to try to get air to the drivers side?

what if i want to let the air out of the bus and set her down on the ground? how do i do that. Where's all the MC9ers out there. Help an uneduacted busnut out.

6 hours ago i really wished I had my schoolie back....she wasn't so difficult. But now i've got a new positive attitude......

Sammy · April 18, 2008, 02:29:40 PM

Greg, relax.
Don't go under your bus at all.
Do this first:
Open the last small side door on curbside, just behind the curbside tag wheel.
Look on your right side,inside the compartment. There should be 2 small valves that control air flow to your tag axle bellows. Make sure they are in the proper position - air "on".
On the inside of that same small door you just opened, there should be a decal to show you proper position of these valves.Check the maintenance manual too.
Don't go under your bus until you know how to properly support the body and the chassis.
Air suspensions can KILL you, if not handled properly.
Best of luck with your new bus.