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  • Kneeling system?

    Posted by Ron on November 14, 2012 at 1:20 pm

    This is an odd
    question, but feel free to consider the source. I’m looking for arguments
    against disabling the kneeling system on my formerly seated coach. So long as I
    am able to date young athletic women, I can think of no situation where I will
    ever need to reduce the height of that first step to enter my coach. I can put
    a step stool on the ground if I get so feeble I need one for myself. The issue
    came up when I discovered a significant air leak that I traced to the exhaust
    port of the front ride height valve. When replacing the valve with a new one
    made no difference, I bench-tested the original and found it operated normally.
    The only way I could duplicate the leakage was to have less air pressure at the
    supply port than at either port that delivers air directly to the air springs.
    In my feeble troubleshooting efforts, I’ve only been able to surmise that the
    Norgren valve supplying air to the front kneeling air tank is failing to shut
    off the flow when it is commanded to do so. To correct the problem, I can
    replace the valve to stop the leak and retain the original kneeling option or I
    can add fittings to tie the air bags directly to the supply source (like on
    your coaches) and cap off or remove the valves associated with the kneeling
    circuit. I don’t take jerry-rigging a professionally engineered system lightly,
    but I could use that surge tank to reduce the cycling of the air compressor in
    my trailer that keeps the coach aux air topped off. If I finally get all the
    other little leaks stopped, this will be pretty weak justification for changing
    the function of that surge tank.

    Any thoughts you
    experts have will be most appreciated. If you have a source for reasonably
    priced Norgren valves in the Los Angeles or Phoenix areas, that would be very
    valuable to me as well. Thanks.

    Ron replied 13 years, 10 months ago 4 Members · 5 Replies
  • 5 Replies
  • Bob

    Member
    November 14, 2012 at 1:34 pm

    I by passed the one on the 89 for the same reason: Another board member flew Tomcats. Small world. Hope the world finds you in great shape. Back to question presented no problems for the years I owned coach. Just was another place to leak. Spliced line and bypassed controll valve. 1/8 line if memory serves me rite. been 8plus years. Bob

  • Archived

    Member
    November 14, 2012 at 2:02 pm

    Bob, Tomcat drivers can’t be all bad, even if they did fly for that other branch of the military. 🙂 Thanks for your input. ‘Glad you’re still out there.

  • Bob

    Member
    November 14, 2012 at 3:47 pm

    If your bores and spools are good there is a kit available to rebuild them. or just buy orings seperate. The flat one is a little hard to find. If you can come up with a old one take it apart and look at it. I know you did your own maintance on aircraft so well within your knowledge. Most problems are just cracked old o-rings./dry bore problems. Actually a little air tool oil in a sticking valve sometimes is a temp solution and diagonostic tool. By the way my new bionic back is great and I’m pain free! I think you will find bore & spool near perfect with no slick spots or scouring. Bob

  • Davy

    Member
    November 14, 2012 at 6:09 pm

    Ron, I don’t have a dog in the fight, but from my perspective I will guess most places you park are going to be level, and those that are not are likely to be going uphill from the front as often as those that go downhill. With those odds it would be tough to justify the extra hardware and future repeats of the problem. If you indicated you could raise or lower the rear also, I would not have suggested you do away with the system.

    Climbing a high step will keep you healthy.

  • Ron

    Member
    November 15, 2012 at 9:58 pm

    Bob, thanks for
    the Norgren valve info. Since it’s time to go through the entire air system, I’m
    about to learn a lot of new lessons. Congrats on the new back. Now if you can
    just resist the temptation to start tossing things like tires around again…

    Jon, I’ve got the
    full low-buoy, but only the front high-buoy. I used the low-buoy once to quickly
    drop the entire coach to go under a low bridge, but don’t need the frazzled
    nerves ever again. It’s much more comfortable to back up and turn around. The
    full high-buoy would be handy when I need additional ground clearance, but it’s
    hard to picture the need to temporarily raise only the front of the coach. How do you open the door if that little old
    lady is about to step off a loading dock anyhow? I don’t really think I need to
    try to keep up with the Latino kids who have fast acting air shocks on all four
    corners for creative cruising.
    J Thanks for pondering a strange question.

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