Tsssssssssssssssssssssss.........

[JIM CHALOUPKA]

Gordon and Adam, there are many posts on bus support points.
Use the search tool.
I have included one for you.
Your manual also has a diagram.

http://forum.prevostownersgroup.com/...support+points

Dale made his supports similar to what Joe described.

Gordon in theory the hyd. jack is not a proper and safe support because there is the possibility however remote that it will fail in some way and leak down on you. You only need one failure to ruin your day.

Some other things to consider when supporting the bus are you must be on level ground or the bus may tip the supports however strong and send the bus down at a rate of 32ft/sec/sec., that's like faster than you can scoot out from under.
Another is the nature of the surface on which you will be working. The supporting surface must be capable of supporting the weight of the bus concentrated in four points of surface contact. Do not assume that a concrete surface is strong enough. It may be to thin or of a composition that does not have a compressive strength per square inch high enough to support the bus. If your work area is in question place your supports on large pads to distribute the load over a larger area.
If you are at all doubtful do not proceed until you get on site expert help.
I have only offered tips and general info on the topic. I do not make any claim that they are all inclusive or fool proof.

JIM

JIM

[Jon Wehrenberg]

Adam, Orren is correct. However, just to satisfy my curiosity and perhaps lead to an additional problem, does the bus drop as air escapes?

With the bus running, the Norgren valves shift to run aux. air throught the ride height valve you have pictured into the air bags. When the correct height is reached, the arm moves to the center position and air flow, both in or out stops.

When you turn the key off, there is no air supply to the "air in" port on the ride height valve because the Norgren valve directing air flow has gone to the closed position.

That's why I ask the question to see if there is a secondary issue.

[adamdegraff]

Adam, Orren is correct. However, just to satisfy my curiosity and perhaps lead to an additional problem, does the bus drop as air escapes?

With the bus running, the Norgren valves shift to run aux. air throught the ride height valve you have pictured into the air bags. When the correct height is reached, the arm moves to the center position and air flow, both in or out stops.

When you turn the key off, there is no air supply to the "air in" port on the ride height valve because the Norgren valve directing air flow has gone to the closed position.

That's why I ask the question to see if there is a secondary issue.

No, the bus does not seem to drop as air escapes.

Thanks for the help!

~Adam

[GDeen]

Ok, thanks for the input. I spent most of Sunday afternoon under the bus running smartire antenna cable from the rear to the front and thought I was pretty well covered. Will check into some of these additional options.

[Jon Wehrenberg]

Adam, just as I thought.

Question number 2.....is the bus at its normal ride height when you hear the air escaping? And just to clarify, the bus does not lean or sag in the front, but you do have your aux system air go down to zero reasonably fast, correct?

[adamdegraff]

Adam, just as I thought.

Question number 2.....is the bus at its normal ride height when you hear the air escaping? And just to clarify, the bus does not lean or sag in the front, but you do have your aux system air go down to zero reasonably fast, correct?

The bus DOES seem to be at its normal ride height when I hear air escaping. And yes, the aux system air does go down to zero somewhat quickly, though that effects very little on my bus as I don't have air pocket doors.... just the air slide.

Have we reached a verdict?

~Adam

[Jon Wehrenberg]

Adam,

My bad. I had my brain working in reverse and was thinking the Norgren five port valve is ahead of the ride height valves.

I think that ride height valve you pictured has failed, and what appears to be happening is that it is leaking internally and air is escaping. The air in your airbags is trapped by the 5 port Norgren, so the bus remains as it was when you turned off the key, but the air in your aux system is the source of air that is leaking and that air is escaping through the valve.

Replace the valve and you are good to go. The valve shown appears to be the type Prevost used that has a built in delay before it functions. I suggest when you order the valve you make sure you get that type. The other type now used by Prevost is an instant acting valve and has a black plastic case. Personally, I like the type you have.

That is an easy fix, but you have to get under the coach. Please do not get under it unless you have it properly supported. To get the maximum height raise it up on the air bags and use good support under the chassis support points. There is plenty of room for you to slide around on your butt once you are in the area between the two front wheels. Did I say support the coach?

If you do not change the length of the rod that ties to the lever arm on the valve you will not have to adjust your ride height so the replacement will be a simple remove and replace. Don't forget to support the coach.

Jon

[adamdegraff]

Thanks Jon,
My plan is to sleep under the coach tonight, just to get acquainted with it, and then support it tomorrow morning. Will that be soon enough to support the coach?

Just kidding.

Thanks for the help!

Adam

[garyde]

I think one of the most dangerous aspects of working on these Coaches is getting under them. You don't know what you don't know.
Jim C. has some very important points.
When Jon provided Stnds to a group of POG members, it came at the end of several weeks of discussion regarding supporting your coach and where the support points are located.
This endeavor should be approached with extreme caution.

[hhoppe]

Adam: After hearing you perform with your Fiddle (violin) I want you to stay out from under that bus. Take the bus to a truck service shop and pay them to replace the valve. I'm sure you can make a deal with the tech. there not to play a violin and you will not chance damaging highly trained and conditioned fingers and hands. This is your Pa Pa talking Son, so pay attention. Trade him performance tickets for his work and you both will be winners. The Poggers that have heard Adam play will agree with this post.