Level low problem

[ajducote]

I managed to get the bus out this weekend for a short get a way. But ran into a small problem.

The Prevost installed level low system, all manual system, no automatic features.

Set the switch to "front" and I can go "down, but not "up". When I hit the "up" switch I hear a solenoid kick in and a small puff of air, but no air seems to be passing to the airbags.

When the switch is in the "left" or "right" setting, "up & down" works. Or i seems to be anyway. The bus does rise up. Just not sure if it is the rear only or both rear and front.

I read the article on the web site "THE PREVOST SUSPENSION SYSTEM AND REPAIRS (http://www.prevostownersgroup.com/public/index.cfm?fuseaction=articles.view&id=3724&publicationtype=Articles)" http://www.prevostownersgroup.com/public/index.cfm?fuseaction=articles.view&id=3724&publicationtype=Articles

and is suspect that the 2nd from the top solenoid valve may have a stuck spool in it?? Just a very wild guess on my part.

Any suggestions would be appreciated. I would like to track this down and fix it myself if possible, but without spending a lot of effort looking in the wrong places.

Thanks in advance, let the fun begin.

[Joe Cannarozzi]

Andre you have diagnosed that correctly.

All those components are available separately. Brian E posted these parts with a picture. If you have a hard time getting separate components let me know I have a used spool valves, I will send you one.

You can swap it with another to confirm your failure.

[ajducote]

Joe thanks for the confirmation on my guess work. I searched for BrianE 's post and found the pictures. So I took the valve apart (#2 from the top), cleaned the O rings, put it back together, and it works! I suspect there was a little piece of dirt or grit, but I really did not see anything.

Next stop, order a spare looking at Mango Mike's web site, looks like I need part # 641928
http://www.prevoman.com/Pages/Manifold/Manifoldpg2.html

Question:
Is there such a thing a generic 3 port and 5 port Norgren valve? Can I have just 1 spare of each to cover me?

[Joe Cannarozzi]

On the norgrens, yes.

Get a spare electric solenoid that actuates that spool valve you just cleaned and fixed. They fail, easy to check, 0 resistance across the terminals.

[Jon Wehrenberg]

Adding to what Joe suggested....the solenoids are alike, mounted on the manifold. The only critical one on your coach is the center one, which controls the five port Norgrens which bring the ride height valves into play.

We all can suffer a coach out of level until we get around to diagnosing and curing the problem, but we need the ride height portion of the system to be functional or we cannot drive.

Should that one fail to function, just swap it with any other. If that does not cure the problem it is likely one of the three Norgrens that is getting stubborn and the spool is not shifting out of the NC position.

[gmcbuffalo]

I could not get my right rear to raise with the loLevel. So I started swaping parts in the drivers side front compartment. Seems if I put the coil and wiring for the left rear side on the valve post for the RR the bus would go up. Good no problems from there back. I took the coils apart, put the LR (working) coil on the wiring for the RR valve, still not working. Put the RR coil on the wiring for the LR, Works. Good don't need new solenoid or coils. I then didn't continuity check of the wiring to the switches, no breaks in wires. Boiled it down to the two switches. The position switch looked expensvie so I started with the rocker switch and it turned out to be the problem. A 9 pin switch three inputs from the position switch and 6 outputs to the solenoids. Every post worked but the one to lift the RR. Noticing some greasy looking lint around the rocker I decided to clean the switch with some elctrical spray cleaner. Bingo my friend. It started working again.

So as Jon's say you can swap around like parts to diagnose problems, if you want to spend the time. But it does feel good doing it yourself and it works.
GregM

[phorner]

Joe thanks for the confirmation on my guess work. I searched for BrianE 's post and found the pictures. So I took the valve apart (#2 from the top), cleaned the O rings, put it back together, and it works! I suspect there was a little piece of dirt or grit, but I really did not see anything.

Next stop, order a spare looking at Mango Mike's web site, looks like I need part # 641928
http://www.prevoman.com/Pages/Manifold/Manifoldpg2.html

Question:
Is there such a thing a generic 3 port and 5 port Norgren valve? Can I have just 1 spare of each to cover me?

Just be careful...... even BRAND NEW OUT OF THE BOX Norgren valves have been known to leak....... right, Joe ?:eek:

[Joe Cannarozzi]

Paul there is 1 3-port in the steering bay that is actuated with an electric solenoid instead of air. The rest of them all look alike but what do I know.

Great work Greg. How many other projects did the job spawn:confused::o:D:rolleyes:

[Jon Wehrenberg]

On Paul's bus and all Libertys there is a 3 and 5 port Norgren on the rear wall of the steer compartment, both operated pneumatically via the solenoids on the same rear wall.

There are also 2 solenoid operated three port valves and these are located ahead of the computer box.

[gmcbuffalo]

Joe I figured out how the little bubble level is mounted and how to make it read accuracely. On mine there were three allen head screws that work just like the air bag controls, two for the rear and one for the front. Level bus with carpenters level, then turn screws to move bubble to the center of circle.
GregM