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Another TNT platform issue…

Discussion in 'Technical Discussion' started by Pascal, Apr 19, 2025 at 11:17 AM.

  1. Pascal, Apr 19, 2025 at 11:17 AM
    #1
    Pascal

    Pascal Senior Member

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    The second stage of our TNT platform starts sagging on one side after a little while. No external leaks at any hose or fitting

    as a test, we filled the reservoir and placed shop towel around the filler. After an hour the second was down a little and fluid had spilled out of the tank

    I am guessing the valve in the valve block is leaking and allowing fluid to be pushed back under pressure? Can they be disassembled and cleaned ?
  2. Capt Ralph, Apr 19, 2025 at 12:23 PM
    #2
    Capt Ralph

    Capt Ralph Senior Member

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    You are our lift expert,,, Your asking us??
    rtrafford likes this.
  3. rtrafford, Apr 19, 2025 at 2:19 PM
    #3
    rtrafford

    rtrafford Senior Member

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    Couldn't it also be caused by a bad seal in the sagging cylinder? Possible to cap the lines to that cylinder and retest the block? Perhaps you can further isolate the issue before the dismantling begins?
  4. Pascal, Apr 19, 2025 at 4:42 PM
    #4
    Pascal

    Pascal Senior Member

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    A bad seal in the cylinder who result in a leak outside the cylinder. It s not the case. The pressure in the cylinder is held at the pump.
  5. Pascal, Apr 19, 2025 at 4:43 PM
    #5
    Pascal

    Pascal Senior Member

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    Well I m guessing the pump design is fairly standard, it’s not like TNT makes them. I was hoping someone had disassembled one before
  6. Capt Ralph, Apr 19, 2025 at 5:06 PM
    #6
    Capt Ralph

    Capt Ralph Senior Member

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    Well, If the ram piston seal was leaking, the cylinder could sag even though the pump check valve is holding.
    You would never see an external leak.
    I'm assuming 2 line cylinders.
  7. Pascal, Apr 19, 2025 at 6:44 PM
    #7
    Pascal

    Pascal Senior Member

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    I m no hydraulic expert but whoever I ve had a leak at a piston, it was pretty obvious. Especially above the water with a very obvious sheen

    yes 2 hoses on the cylinder
  8. Capt Ralph, Apr 19, 2025 at 6:51 PM
    #8
    Capt Ralph

    Capt Ralph Senior Member

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    Then an internal piston leak is possible.