Trailer suspension issue

Discussion in 'Trucks [ Eighteen Wheelers ]' started by Cajuncowboy654, Jan 18, 2021.

  1. Cajuncowboy654

    Cajuncowboy654 Light Load Member

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    20210118_165750.jpg

    Is the port circled supposed to have air coming from it at all times or is it supposed to be an exhaust?

    Its on a manac stretch trailer with a lift axle that I bought. There is a petcock on the end of the hose and the fitting leaks constantly.

    My leveling valve was leaking from the exhaust so I changed it and its still doing the same, wondering if this valve is bad and causing the leveling valve to leak.
     
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  3. ibcalm19

    ibcalm19 Heavy Load Member

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    You bought a new leveling valve & it is leaking also(if I understand correctly) I would change that valve I believe it is not seating. I had similar issue on a regular dry trailer valve leaking.
     
  4. Cajuncowboy654

    Cajuncowboy654 Light Load Member

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    Yes the new one is leaking also.
    I adjusted it and it stopped for a while but then it will start letting air out of the exhaust again.

    I'm also trying to find out about the valve block pictured to know if I need to plug that line to stop it from leaking or if its supposed to be an exhaust and it is stuck open and the previous owner out a petcock valve to stop the leak in error
     
  5. ibcalm19

    ibcalm19 Heavy Load Member

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    What year is your trailer if I'm looking at that valve it looks like it is date coded for 06. If so I would say it has served itself well. Either way I would change it. I don't believe the exhaust port would be wise to plug I'm pretty sure it's is open for excessive pressure build up. That is probably why it is leaking it has worn out or debris is not allowing it to seat properly.
     
  6. Cajuncowboy654

    Cajuncowboy654 Light Load Member

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    Its an 08.

    Of course the exhaust port shouldn't be plugged, but the problem is, I dont know if it is an exhaust port or not. There are no markings and Google hasn't been much help.

    The end of the hose connected to that port has a push fitting with a petcock on it like the ones used to drain an air tank.
     
  7. xsetra

    xsetra Road Train Member

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  8. Cajuncowboy654

    Cajuncowboy654 Light Load Member

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    Yes I know that much.

    Just can't find any diagram or info pointing to which port does what so I can see if its an exhaust port or not
     
  9. xsetra

    xsetra Road Train Member

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    A manac dealer should have access to a schematic of the air system.

    I have called the factory a couple times. They have been very helpful.
     
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  10. Cajuncowboy654

    Cajuncowboy654 Light Load Member

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    Would anything else cause the leveling valve to constantly leak from the exhaust other than the valve being bad??
     
  11. Cajuncowboy654

    Cajuncowboy654 Light Load Member

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    So I traded to see where this valve comes and goes.

    20210121_155255.jpg

    The line circled in red, comes from the air bag side of the leveling valve
    The line in yellow goes to the bags.
    The blue circled line goes to a valve coming off the air tank.

    The purple one hangs down and has the push fitting with the petcock on it. Pictured below.

    20210114_134717.jpg


    Below is a picture of where the blue circled line goes, which I believe is the signal line for the valve 20210121_155340.jpg


    Anyone know yhe reason for this valve?
     
    Last edited: Jan 21, 2021
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