Coach Lean

[Gary Winzenburger]

Our 40' 1997 Marquis is experiencing a right side lean going down the highway. It's built on a Gillig chassis using air bag suspension. I haven't weighed the coach, but I haven't added a lot of extra's beyond folding chairs and a portable grill. We're planning a long trip in September, so any idea's on what might be the problem would be greatly appreciated. Also, anyone doubting the importance of using surge protectors, ours tripped in the middle of a rainstorm showing more than 141 volts coming from the shoreline panel box. No apparant damage done. Of course, the campground checked it, and found everything was fine on their end!

[Steve Huber Co-Admin]

Gary,
Sounds like you've got a low air bag on the right side or an overinflated one on the left. If the Gillig is similar to the Magnum chassis, the bags should all be inflated so the distance between the top and bottom plate that the airbags mount to is 9.75 to 10.5". Yours may be different but all bags should be close to same measurement when coach is at ride height.
If a bag is off, it could be caused by an air leak or a leveler adjuster that has slipped. An adjustment can be made relatively easily but unless you have a way of supporting the coach frame, I wouldn't attempt it as a mistake can cause the to drop to the axles very fast.
Steve

[John Maguire]

To make any adjustments you will have to get under the actual Neway suspension member so you better have a good jack and some blocking ready before you go adjusting anything...Gillig uses a semi type setup with a leveling valve on either side of the frame controlling air bag volume that adds air by forcing the vertical rod you will see pointing down forward or reducing pressure by moving backwards...they are connected by a sliding rubber connector on the rear and a rubber hiem type joint on the front...it's pretty basic to determine if the valve is frozen up by loosening the sliding rubber connector and moving it towards the front of the bus...you will then see the airbag fill (engine running)if the valve itself is operating as it should..again be wary of anything that may be impacted by the bus suddenly rising if you have it blocked...if it does indeed rise as it should you will en have to begin debugging the leveling system which can also potentially get hung up..sometimes the vertical rod which is attached at the top by a 1/4-20 tensioner bolt can loosen and the rod will slide down making the geometry ineffective in leveling...most common is a valve failure however and they can be a bugger to get at the backside of the bolts. This all assumes you are interested in actually crawling under there...lol

[Gary Winzenburger]

Thanks John and Steve for the information. I'll go so far as to crawl under the back axle to see what you both are talking about and then decide if I want to tackle it.
Gary