Aux Air Leak??

[0533]

When I arrived at my current destination I manually leveled the coach before turning it off. After turning off the bus I went outside so that Pam could extend the slide out. This process requires that we unlock the key which is an Aux Air driven device. All worked fine, and the slide went out without a hitch.

I then heard what sounded like air leaking from the steering bay, opened it to hear air escaping from a small red plastic valve release or over pressure device (see attached image).

When I placed my finger over the opening, bottom red plastic valve, adjustable to some degree, attached to a small black square box which has a black air line coming in the air stops, but after a few seconds the 75psi blow off valve blows off the excess air pressure. I thought that all that was happening was that I had a few extra pounds of air in the system and it was bleeding off until it reached the correct pressure. I decided to wait until the next morning to check.

I have checked the pressure and there is none in the aux air side which can be isolated by a valve for the slide out and pocket doors etc. I filled it back up and it is leaking back out at the same point, the little red plastic valve at the bottom of the row of 5. There are 6 lines, 2 black lines at the top, red green and yellow and black at the bottom underneath, its the black line at the bottom that leads back to a Norgren valve a few inches away.The leak is at the little red screw valve at the bottom black box.

Question: Is there a simple fix or do I need to replace the valve, as I call it, ie. the little black box with the red plastic pressure screw on it???

Thanks.

Bruce

[garyde]

Hi Bruce. Those are your solonoid valves, essentially your interface between your electrical system and your air system. Jon would know if they can be fixed, in a pinch you could swap one for another like your slide out floor.

[JIM CHALOUPKA]

Bruce there is in all likelihood a way to mechanically cycle the solenoid valve, such as pushing the piston/spool/valve with a tool such as a small screwdriver. You can shuttle it back and forth, to loosen and or displace a small piece of dirt or alleviate a "sticking of the valve".
I know this works on hydraulic valves, and should work on air.
If you get it to work, let this be your first warning and get yourself a replacement to carry for the next time it happens, as it surely will!
These solenoid valves are an excellent candidate for the spare parts to be carried on the bus.

[0533]

Hi Bruce. Those are your solonoid valves, essentially your interface between your electrical system and your air system. Jon would know if they can be fixed, in a pinch you could swap one for another like your slide out floor.

Thanks Gary for the quick response. Your answer opens up some new questions that I will have to better understand I guess, including where each line goes to, seats doors slide etc. I will give it a go. Still wonder why this happened all of a sudden.

I have been having some intermittent IRSI (Pice of sh..) seat problems with one line that comes off. I had all line connections replaced , but they missed one. Slide locks work great, pocket doors and bed lift, I need to stop the leak some how. The odd thing is when I have the pressure at 75lbs and place my finger over the solenoid that is leaking the pressure over flow valve blows off in about 5 seconds or so, can't figure this out.

I am clearly challenged in this area and will need a crash course.

Thanks.

[0533]

Bruce there is in all likelihood a way to mechanically cycle the solenoid valve, such as pushing the piston/spool/valve with a tool such as a small screwdriver. You can shuttle it back and forth, to loosen and or displace a small piece of dirt or alleviate a "sticking of the valve".
I know this works on hydraulic valves, and should work on air.
If you get it to work, let this be your first warning and get yourself a replacement to carry for the next time it happens, as it surely will!
These solenoid valves are an excellent candidate for the spare parts to be carried on the bus.

Jim , good idea and I will try this, but you have just said something about spare parts. Marathon created a spare parts box for me, will check it out and see what I have in the goodie bag.

If I find one, how do you replace it?? Do they come apart separately?? I am going to check for one now.

Thanks

[BrianE]

Bruce, Your photo shows the manifold valves (solenoids) that control your leveling system. They do fail but can normally be repaired.

Before doing that however, suggest that you re-level the bus then return the leveling system to the road position and immediately turn off the ignition key to prevent the bus from returning to road height. This seems to neutralize the valves in the off position and prevents leakdown. I'm sure Jon will be able to explain why. Adding one of these valves along with some O rings to your spares kit is a good idea.

To inspect/repair the solenoid, dump your leveling system to zero then remove the spring clip under the red screw. This will allow you to slide the solenoid magnet from the valve body and making 4 phillips screws accessible. Using a #1 phillips screwdriver, remove the 2 long machine screws from the valve body and remove it from the manifold. There are a large and small O ring on the bottom of the body which should be replaced. While you have it in your hand, remove the other two flat head screws from the body and carefully separate the two halves. You will find a spring and valve seat, inspect the rubber valve surface for nicks, dirt or uneven wear, if the seat is damaged replace the valve body.

I just took some pics of the disassembly process but noticed Jim C and Gary have chipped in. Will have the photos on line in a few minutes.

[BrianE]

Sorry about the focus, Dale will be ashamed of me.

[JIM CHALOUPKA]

Some have a single small screw in the center of the electrical "plug" on one end (the part with the wires)

Loosen the screw and wiggle off the plug.

Examine the valve body to discern the way in which it is mechanically mounted to the switch block, and loosen that mounting. (save all screws, as they will be needed for remounting the new valve)

Swing the old valve, still attached to the air, out of the way and mount the new valve to the switch block.

Remove the airline and fitting from the old valve. Install the existing line and fitting to the new valve. (best to have the air off), but could be done in a pinch with air in system (work quickly).

[JIM CHALOUPKA]

Brian, your camera needs cataract surgery.

[dreamchasers]

Bruce,

The attached link will provide log on information to the Suspension Presentation that Jon and I gave at Seiverville this year. It should help with the basic features of the suspension. I am sure your particular coach converter added its modifications. The presentation was based on a prevost drawing for my version of coach, 1995.

If Jim Skiff reads this message, please get in touch with me to coordinate providing a link to this presentation directly from this site for easy access by POG members.


http://forum.prevostownersgroup.com/...ead.php?t=2116


Good luck,

Hector