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  • Location of 5 port Norgren Valve ?

    Posted by Archived on November 5, 2019 at 10:03 pm

    Just read Jon’s February 2012 article entitled Diagnosing Suspension Problems in an attempt to figure out a current problem.

    Near the end of the article, it describes my current problem – leans to the left. Can anyone tell me where to find the five port Norgren valve that controls the rear LH side of the coach. (I see from the article, the three port is located between the drive and tag air bags) Thank you!

    P. S. – why would such a problem be sometimes intermittent? For nearly the past two weeks, the rear left would drop 2+ inches over night and I would raise it daily. Now the past two days, it has held full pressure without leaking.

    Cut and Pasted from the Article:

    If the coach leans to the left for example, the only place air can leak from the three rear LH air bags is through a defective or leaky air bag, one of the fittings associated with the three LH air bags, through the three port Norgren valve between the drive and tag air bags, or though the five port Norgren valve.

    Jeff replied 6 years, 10 months ago 14 Members · 20 Replies
  • 20 Replies
  • Ronald

    Member
    November 5, 2019 at 10:52 pm

    It is located on a bulkhead that runs east/west just forward of the drive axle

  • Art

    Member
    November 6, 2019 at 7:50 am

    Here’s where “the leans” will drive you crazy. First it is intermittent meaning it may not be leaking when you are trying to find the leak. Then if it becomes a continuous leak (cold temps tend to do that) you have to understand how the system works and focus on a procedure that will limit your efforts to just those areas associated with the left leans.

    The concentration on the system from the 5 port on the bulkhead through the fittings, air bags, 3 port and all fittings is correct, but because you have a Liberty you have one other potential leak and that is one of the solenoid operated 3 port Niorgrens in the steer compartment. Use the level low to lower the LH rear and whichever of the Norgrens in the steer compartment is exhausting air is also to be checked.

    If you do not need the leveling feature to work during the diagnosis plug the exhaust port on the Norgren in the steer bay and see if it leans. Then do the same with the 3 port between the drive and tag. The frustrating part of all of this is a Norgren valve can leak internally and air can escape through the end caps so it makes a difficult bit of detective work harder. If you sense you need to spend a lot of time inflating and waiting, in addition to spraying soapy water you are correct. At some point you may find yourself disconnecting fittings and pressurizing individual components or sections to attempt to narrow the search.

    The coach as it ages can have leaks in the valves, at the push in fittings, and even the air bags so if you have time and patience you can eventually isolate the leak(s) or you can just use a scorched earth resolution and change everything. At some point you have to do that anyway and depending on the coach and where it spent its life it may or may not be approaching that point.

  • Mike

    Member
    November 6, 2019 at 9:08 am

    I use Bird Dog spray to find leaks it can be found in air condition supply lots better than soapy water

  • Archived

    Member
    November 6, 2019 at 9:20 am

    Jeff when we 1st bought our bus,parked it would lean to the right when you leveled it, but not always, finally found the right rear tag bag was old and rotted right where it rolls around at bottom if it was lower it wouldn’t leak or higher it wouldn’t leak either, when the little bad spot was in the roll position it leaked bad. In trying to track down that problem I also replaced level valves and the check valve on level valve. I’ve replaced all the air bags and 3 level valves and check valves.

  • Fred F.

    Member
    November 6, 2019 at 9:29 am

    If leaks are in the air bag they can be a special challenge. The bottom “can” is steel and can rust so you lose pressure, but because it is surrounded by a plastic piston the rubber rolls over as it flexes you cannot get soapy water or any leak detector at that point or see any bubbles if you could.

    Leak detection involves ears, a stethoscope, soapy water, and ultrasonic leak detector or a means of pressurizing a system or part of a system to look for pressure drops. There is no single method of finding all leaks that is best. Each method has its benefits and shortcomings.

    But if I were to guess, on a 2007 with original parts my first task would be to spray every fitting and valve and make sure I also spray the joint at the end caps of the valves and exhaust ports. From that point on it gets difficult and tedious, and very expensive if you hire someone to do the leak checking.

  • Archived

    Member
    November 6, 2019 at 10:24 am

    Jeff

    you have the same problem I did when I purchased our coach . we replaced leveling valves ,NV and it turned out to be airbags ..

  • Archived

    Member
    November 6, 2019 at 12:52 pm

    cooler weather makes push fittings air lines leak more. If you start replacing air parts switch to compression.. Personal experience for a long time with this.

  • Jeff

    Member
    November 7, 2019 at 6:33 am

    And don’t forget the R-12 valve which interlocks the tag brakes when it is raised.

    The R-12 pilot air supply is between the 3 port Norgren and the tag bag. Even after new bags and new norgrens mine still leaked and leaned. Until i replaced the R-12.

  • Chuck & Katrina

    Member
    November 7, 2019 at 10:18 pm

    Great information – THANK YOU ALL VERY MUCH


    2000 Featherlite H3-45

    2024 Jeep Grand Cherokee

    Leesburg, FL
  • Roy

    Member
    November 8, 2019 at 6:12 pm

    one more ==Use gray teflon tape on air fittings –reduces possible leaks.. Learned from departed member.. he was correct. some knowledge lives on!

  • Mike

    Member
    November 8, 2019 at 6:57 pm

    What’s the difference between the white & gray Teflon tapes?

    Chuck

  • Dick

    Member
    November 9, 2019 at 6:15 am

    Just for info. Teflon tape colors

    • White: used on NPT threads up to 3/8 inch
    • Yellow: used on NPT threads 1/2 inch to 2 inch, often labeled “gas tape”
    • Pink: used on NPT threads 1/2 inch to 2 inch, safe for potable water
    • Green: oil-free PTFE used on oxygen lines and some specific medical gasses
    • Gray: contains nickel, anti-seizing, anti-galling and anti-corrosion, used for stainless pipes
    • Copper: contains copper granules and is certified as a thread lubricant but not a sealer
  • Tim

    Member
    November 9, 2019 at 8:41 am

    Thanks Mikee

    Wow, didn’t know there was that many. Just goes to show you never stop learning

  • Chuck & Katrina

    Member
    November 9, 2019 at 8:41 am

    Thanks Mikee

    Wow, didn’t know there was that many. Just goes to show you never stop learning


    2000 Featherlite H3-45

    2024 Jeep Grand Cherokee

    Leesburg, FL
  • Archived

    Member
    November 9, 2019 at 11:21 am

    I experienced less problems with gray than white. Not much price difference. Good explanation!! I do use stainless fittings(compression) why? because I have a large supply of them…free. Have brass and stainless in use. Never knew exact science just results..Seams like white has a tendency to shred during instalation when I use.

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