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  • Slide Suspension interaction

    Posted by Darcy on June 1, 2017 at 4:27 pm

    We
    were leaving our lot in Indio in April this year for home and one of the pins
    on my front slide didn’t set properly. I was able to get a hold of Jeff who
    helped work around the issue and get them all set properly and we were able to
    travel. It seemed like the slide was binding a bit coming in, and Jeff made a
    comment that made me really think about my suspension system. He said that once
    the coach had levelled off in the RUN position the slide should just smoothly
    move. I had noticed for some time that I had to manually raise my coach after
    being parked, it wouldn’t just rise to travel height on it’s own?? Jeff’s
    comment started me thinking and I spent a lot of time reviewing my air diagrams
    to fully understand what was going on. I realized that perhaps my leveling
    valves weren’t working properly, BUT it wasn’t just one valve, all the coach
    would not rise. Reviewing how the system works, the pilot air lines to the
    front and rear Norgrens are from the front control solenoid valves to supply
    air from either the Level Low or the RUN side of the Norgrens to position the
    spool in the appropriate position. As I operated the level low switches
    (Liberty system), I could feel and hear the solenoid valves click while cycling
    the various three positions (RR, LR, Frnt) on the Level Low system. When I put
    the switch into the RUN position the drive solenoid did nothing, I had 24 volts
    on the solenoid but no sound. I removed one of the pilot lines and installed a gauge
    on the valve, and when I switched the system again over to RUN, No pressure was
    on the gauge. Therefore no air pressure was being supplied to the Norgrens to
    put the Bus into the Run position in the suspension. I changed the pilot Valve
    Bank and am saving the old manifold in case I have to use the good solenoid
    valves in the future. Everything works fine now, coach raises on RUN, air
    pressure is getting to the pilot lines, all is good. I suspect my sporadic slide
    issues are now also solved with the slight coach twisting being stabilized with
    the suspension working properly.

    Jeff
    was a tremendous help getting me going, but also helping to flag to me that
    something wasn’t right. I just wanted to share this bit of learnings as I
    appreciate reading so much information on this forum to expand my knowledge, I
    like to share my experiences as well to hopefully help others.

    Kirby replied 9 years, 3 months ago 3 Members · 2 Replies
  • 2 Replies
  • Archived

    Member
    June 1, 2017 at 4:52 pm

    Darcy has explained what is just about the most common leveling system failure and that is the center solenoid valve in the 5 (or 4) valve stack fails. That is the valve that is energized at all times when the coach is being driven and the coil on the solenoid valve is the typical failure.

    If you suspect your coach is not going to the driving height, or staying at the driving height it is very easy to verify the center solenoid valve is functioning. With the engine running (or just the key on) and air in the accessory system identify the center solenoid valve and loosen the compression fitting associated with the valve. If air escapes the vale is open and functioning. That means the problem is elsewhere.

    But if the valve is not opening, and no air escapes, the first and easiest next step is to swap the coil on that solenoid valve with any other in the stack (AS LONG AS YOU DO NOT HAVE A LIBERTY CLASSIC). Keep the wires with their respective valves. A couple of screws will remove the wire connector from the coil and there is a snap ring that allows the coil to come off the valve stem..

    If you have a Liberty Classic check the voltage rating for the coils and replace a bad coil with one of the correct voltage. I believe the center coil on a Classic is 24 volts, but the other coils are 12 so you may have to carry a spare 24V coil.

  • Kirby

    Member
    June 1, 2017 at 7:29 pm

    Common problem with the center coil and valve. That center one is energized with the ignition and gets REALLY hot.

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