Page 2 of 4 FirstFirst 1 2 3 4 LastLast
Results 11 to 20 of 31

Thread: raise and lower cab

  1. #11
    4 Star General NDT's Avatar
    Join Date
    Dec 2008
    Location
    Camp Wood/LC, TX
    MVPA
    4954
    Posts
    6,925
    Thanks
    1,985
    Thanked 3,279 Times in 1,757 Posts

    Default

    Sounds like trash is being circulated in the system. Personally I would start at the easy place, the fittings at the lift cylinder. Remove them and look for chunks of crap inside. Usually that is where the flow restrictors are, I don't have TMs handy presently.

  2. #12
    4 Star General Steel Soldiers Vendor m-35tom's Avatar
    Join Date
    May 2007
    Location
    eldersburg maryland
    Posts
    2,736
    Thanks
    103
    Thanked 577 Times in 366 Posts

    Default

    System is extremely clean and no sign of water or trash. Pump will operate suspension usually, cab up sometimes but not cab down. Spare tire for 2" then never again. Cab will not open past where the cylinder pushes it. The pin will not slide up in the loop at end of cylinder. So brace never goes over center into safe area. Strange. This truck has been possessed in so many ways I think the devil lives in it.

    I took out the 3 top spool valves, fluid pumps easily into which ever is selected by bottom valve.
    tom bauer m-621
    air conditioned - 28 air
    6 wheel drive - 3 air lockers
    power steering - hydraulic - over 250 kits sold
    fast - now 1 of 43 with .69 od !!!
    m-35 transmission expert
    avatar - 64mph @ 2400 rpm with 14.5R20XL

  3. #13
    4 Star General NDT's Avatar
    Join Date
    Dec 2008
    Location
    Camp Wood/LC, TX
    MVPA
    4954
    Posts
    6,925
    Thanks
    1,985
    Thanked 3,279 Times in 1,757 Posts

    Default

    None the safety braces on my trucks go overcenter either. Yes these trucks are no G742, they all have these type issues and much worse too. Spend some time searching the FMTV forum for bizarre problems other people have had with the cab lift. There have been several resolutions posted by folks.

  4. #14
    4 Star General Steel Soldiers Vendor m-35tom's Avatar
    Join Date
    May 2007
    Location
    eldersburg maryland
    Posts
    2,736
    Thanks
    103
    Thanked 577 Times in 366 Posts

    Default

    Looking at the design, it seems apparent that it was intended for the cab weight to go further forward so the cab brace would fold on itself and lock. I cannot find any reason the cab stops where it does.
    tom bauer m-621
    air conditioned - 28 air
    6 wheel drive - 3 air lockers
    power steering - hydraulic - over 250 kits sold
    fast - now 1 of 43 with .69 od !!!
    m-35 transmission expert
    avatar - 64mph @ 2400 rpm with 14.5R20XL

  5. #15
    4 Star General Steel Soldiers Vendor Suprman's Avatar
    Join Date
    Feb 2013
    Location
    Stratford/Connecticut
    Posts
    6,229
    Thanks
    19
    Thanked 2,144 Times in 1,417 Posts

    Default

    The cab brace should fold out and lock when the cab is fully open. I had a truck that was giving me hyd function issues I swapped the control box and all was good. I had planned on taking the bad one apart and see what was going on with it but haven’t gotten to it.

  6. #16
    4 Star General Steel Soldiers Vendor m-35tom's Avatar
    Join Date
    May 2007
    Location
    eldersburg maryland
    Posts
    2,736
    Thanks
    103
    Thanked 577 Times in 366 Posts

    Default

    It should fold forward so the bottom part hits the pin it the top part?
    Last edited by m-35tom; 01-25-2019 at 22:57.
    tom bauer m-621
    air conditioned - 28 air
    6 wheel drive - 3 air lockers
    power steering - hydraulic - over 250 kits sold
    fast - now 1 of 43 with .69 od !!!
    m-35 transmission expert
    avatar - 64mph @ 2400 rpm with 14.5R20XL

  7. #17
    4 Star General Steel Soldiers Vendor Suprman's Avatar
    Join Date
    Feb 2013
    Location
    Stratford/Connecticut
    Posts
    6,229
    Thanks
    19
    Thanked 2,144 Times in 1,417 Posts

    Default

    The arm folds open and locks out. As best as it can for what it is. So if you push on the cab it’s locked open. And to start closing it, takes hyd action to pull the cab and arm back.

  8. #18
    4 Star General Steel Soldiers Vendor m-35tom's Avatar
    Join Date
    May 2007
    Location
    eldersburg maryland
    Posts
    2,736
    Thanks
    103
    Thanked 577 Times in 366 Posts

    Default

    So the oblong part in the odd shaped slotted end on the cylinder moves to the top? Mine will not move, rust maybe.
    tom bauer m-621
    air conditioned - 28 air
    6 wheel drive - 3 air lockers
    power steering - hydraulic - over 250 kits sold
    fast - now 1 of 43 with .69 od !!!
    m-35 transmission expert
    avatar - 64mph @ 2400 rpm with 14.5R20XL

  9. #19
    4 Star General Steel Soldiers Vendor Suprman's Avatar
    Join Date
    Feb 2013
    Location
    Stratford/Connecticut
    Posts
    6,229
    Thanks
    19
    Thanked 2,144 Times in 1,417 Posts

    Default

    I have seen the whole oblong assembly installed backwards. B2C62392-A75F-4E22-A803-B83149D656F8.jpgYou can see bottom right of the pic the lock arm is fully open.

  10. #20
    4 Star General Steel Soldiers Vendor m-35tom's Avatar
    Join Date
    May 2007
    Location
    eldersburg maryland
    Posts
    2,736
    Thanks
    103
    Thanked 577 Times in 366 Posts

    Default

    That arm is not open or locked. It looks just like the position mine gets to. Not far enough.
    tom bauer m-621
    air conditioned - 28 air
    6 wheel drive - 3 air lockers
    power steering - hydraulic - over 250 kits sold
    fast - now 1 of 43 with .69 od !!!
    m-35 transmission expert
    avatar - 64mph @ 2400 rpm with 14.5R20XL

Page 2 of 4 FirstFirst 1 2 3 4 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •