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  • Aux air system and Tag drop

    Posted by Marius on March 21, 2017 at 9:15 am

    Starting a new thread so that I can get this sorted out if anybody is willing to help with specific info.

    I will definitely start the hunt for leaks once I get the bus in the shop and up on stilts.

    Just to understand this correctly….the tag will not drop if the Aux system is maintained at over 35 psi ? How is that accomplished ? There will be some leaks…..Is the 12V compressor supposed to add enough air into the system to keep pressure that high ? There is no 110V compressor on this vintage.

    I don’t have an air operated toilet or pneumatic doors on this coach….so air is only for leveling and generator slide…unless I am missing something.

    Would like the get a new set of Norgrens for a decent price. Has anybody compiled a list for the early 1990 XL and would be willing to share so that I can buy them all ?

    I can see merit in Jon’s suggestion. $1800 for those valves is rather steep……and addresses only one issue.

    On a 40 footer the tag lift is not that critical as it is on a 45 when maneuvering tight turns….does not drag much really and with the solid axle upfront, the turning radius is not very tight anyway.

    Now ….if the tag would be double duty- dump and/or raise to take some addtional weight off the drive axle when needed (like Newell does), that would be a whole different story….

    Tim replied 9 years, 6 months ago 3 Members · 3 Replies
  • 3 Replies
  • Tim

    Member
    March 21, 2017 at 9:20 am

    The way your system works is the aux pressure keeps the 3 port Norgren open such there is a path between the drive and tag air bags. When that pressure is lost the Norgren shifts so the air from the drives is locked in, but the tag axle air bag air is exhausted. The reason for the $1800 is there is more going on back there, and the fix had to take that into consideration. When you lift the tag manually you also disable the brakes on the tag so the fix has to address that issue also. I also think above a certain speed the tag is going to drop but I am not sure of that.

  • Tim

    Member
    March 21, 2017 at 6:39 pm

    As Jon pointed out, there is much more going on for the Reverse Tag Logic than simply replacing valves.

  • Archived

    Member
    March 22, 2017 at 10:28 am

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