Air Over Hydraulics System

[dreamchasers]

I am one of the Prevost owners that has the air over hydraulics system installed on my 45'XL. This system was offered as an option for a few years during the mid 90's and not every coach would have the installation. Jon W. has mentioned that his coach has the option also and his comments are positive about the action of the system. He has posted a past topic about the operation of the system. My attempts to get documented information concerning this system has lead me to Josyane Cote, Manager of Technical Publications and Tech Rep, Prevost Canada. She was able to locate two drawing referencing this system.

I contacted her asking for a hydraulic bleeding procedure for after I rebuild the two hydraulic shocks (Mine are leaking), thus, the hand writing on one of the pdf files. I will make available any additional information I receive.

I have uploaded the two pdf files to my site for any one that is looking for documented information concerning this system . Documentation is very hard to find.

http://dreamchasers.us/pog/image-1250910-0001.pdf

http://dreamchasers.us/pog/image-1250910-0002.pdf

I am not sure if the forum is the correct place to make the information available? If another method exists, please advise.

Any Comments?

Hector

[Joe Cannarozzi]

Hector

There are no rules here and you can put that info anyplace that suits you.

Great info.

Don't be alarmed or disappointed if Jon does not respond he is not online while traveling. Go figure:eek:

From the first time I heard of that feature I liked it.

I have gotten in the habit of using the tag dump at most corners and I know it is saving tires and suspension components. I am concidering moving that air toggle to a more convenient place as the stock location sucks. It should be just forward of the trans gear selector or somewhere very convenient so it could be easily used more frequently.

[Jon Wehrenberg]

The information belongs in the front of the POG site under Information Sharing.

Jim Skiff or JPJ, can you guys work your magic so it can be accessed there?

[Jon Wehrenberg]

As a related comment, we watched Tom and Nancy as they left ORA at PSL. When they turned the corner at the community building the entire rear of the coach was down. I am surmising that Tom used full LH turn on the steering wheel and his tags were dumped automatically.

If he saw that he would be wanting the stabilisators. None of us ever gets to see our coaches being driven so we are not aware of stuff like that.

[truk4u]

I don't have the automatic dump, it's all manual and I can sure tell the rear end is sagging when the tag is lifted. I wonder some times if we're better of just letting the tires scrub and be done with it, but it just doesn't seem like the right thing to do on tight turns on hard surfaces.

Any other opinions.....

[Jon Wehrenberg]

Tom,

For the benefit of us all and to provide more information Hector and I can use in the Seveirville seminar, are you saying that when you made the LH turn to leave ORA that you manually lifted the tag?

Are you sure your tag does not dump automatically? I understand it may not have the hydraulic rear support system, but I know all 45 footers were originally supplied with automatic tag axle air bag dumping.

[truk4u]

I lifted the tag coming off the site concrete and left it that way until I got straitened out before the guard gate. It is a manual system. If they all had the dump feature, there must be a specific year they stopped doing it. Mine is a 2000, 1999 shell.

Jim Keller - Does yours have the auto dump feature?

[Jon Wehrenberg]

If it is not on your model year coach it likely was dropped as a feature. When the 45 foot coaches were first introduced as MH shells the automatic tag dump was on all coaches.

As explained by Prevost representatives the engineers considered other choices to minimize scrubbing and to keep the turn radius as small as possible. One system considered and discarded was the MCI steerable tag axle wheels due to its complexity.

Even though a coach has the automatic dump feature the driver can still opt to raise the tag axle manually. I have raised my tag manually, but except for times when I need additional weight on the drive axle for traction, I have stopped doing that because the stabilisators are apparently not engaged when the axle is manually lifted.

[JIM KELLER]

Tom, Mine does not have a automatic dump feature. When we left ODR I did the same thing you did and raised the tag untill we were straight. I have always been more concerned about the sideways stress on the aluminum tag wheel than the scuffing of the tire although I also know dragging an automotive tire sideways will damage the belts in the tire.