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John deere 644E boom cylinder rocking at full extension

Discussion in 'Construction Equipment Attachments' started by fast_st, Nov 14, 2022.

  1. fast_st

    fast_st Senior Member

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    So, have a boom cylinder on a 644E, was leaking from all over on the right boom cylinder, resealed and it was dandy, then it started leaking again, found a torn seal on the gland seal, rod seal was fine, resealed, dandy again. Another couple years goes by and its leaking again, gland seal again. Now the job just before the leak was building a block wall and we were lifting those big concrete blocks pretty much all the way up, 12 feet and more.

    We finished up the job and parked Tiny for the week, look at it this weekend. No drips, push down on the bucket, no drips. seal mostly dry. Okay, maybe because it has cooled off, a thought came, run the boom full stroke. Right at the very tip top of the stroke, the right boom cylinder cocks a couple degrees upwards relative to the rod. Cycled up and down a few times to repeat the motion and then on lowering, a few ounces of fluid dribbles out.

    The other side cylinder doesn't seem to wiggle like that. Trying to figure the cause, guessing it could only either be a bent rod or a distorted barrel, maybe flipping the eye 180 would reveal the culprit?

    That assembly is a heavy cuss for certain.
     
  2. Diesel Dave

    Diesel Dave Well-Known Member

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    Sep 29, 2022
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    Location:
    Ontario Canada
    Sounds like a bent rod. There should be signs of scuffling of the chrome on the rod where the bend passes through the gland. A straight edge along the rod will prove it as well.
     
  3. fast_st

    fast_st Senior Member

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    I didnt see any scuffing on the rod, maybe have to pull it out