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644b won't push dirt

Discussion in 'Wheel Loaders' started by Wildbill1561, Aug 5, 2022.

  1. Wildbill1561

    Wildbill1561 New Member

    Joined:
    Aug 5, 2022
    Messages:
    2
    Location:
    Logan UT
    I have an older JD 644b and I'm having problems pushing through a pile of dirt to get a full load in the bucket. I'm changing fuel filters here soon, but it seems like it just doesn't have enough power to push through.

    Doesn't seem like the engine is choking or bogging down, just not enough power with the wheel to get through the dirt. Seems to lift and turn just fine.
     
  2. Rustyfender

    Rustyfender Well-Known Member

    Joined:
    Oct 3, 2021
    Messages:
    109
    Occupation:
    Equipment operator
    Location:
    Ontario, Canada
    Hmmmmm does it feel like it is in 2nd gear?
     
  3. materthegreater

    materthegreater Well-Known Member

    Joined:
    Jul 25, 2012
    Messages:
    181
    Location:
    VT
    Did you check to make sure it's not low on transmission fluid?
     
  4. Wildbill1561

    Wildbill1561 New Member

    Joined:
    Aug 5, 2022
    Messages:
    2
    Location:
    Logan UT
    I'll check tonight... Thanks for the thought
     
  5. JonathanMA

    JonathanMA Active Member

    Joined:
    Feb 15, 2009
    Messages:
    38
    Location:
    Massachusetts
    Theres several throttle linkage pivots that wear out all at the same time resulting in less than max engine RPM, which creates doggy transmission response. With the pedal to the stop on the floor, make sure the injection pump lever is against the stop on the pump --- If not, sometimes a slight upward bend (very stretched out upside down V) in that final long linkage rod can take up some of the slack created by loose pivot points.
     
    DB2 likes this.