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Cat 931B backhoe removal

Welder Dave ยท 2019-09-08 23:44

I was wondering if Cat has a procedure for replacing the bushings in the swing tower on a 5G2150 backhoe? I'd like to leave the rotary cylinder on and hopefully leave everything complete to get at the swing pin bushings. I know I'd have disconnect the link for the rotary cylinder and maybe disconnect the hoses but thought there may a procedure for doing it that shows how to support the boom.

Replies3
  1. #1CAT Dillon2020-01-02 12:33

    I removed the rotary swing unit on a 935B and replaced the seals many years ago. the details have long since been forgotten. The rotary unit is probably 400 Lbs., and will smash anything when it hits the floor. Toes, fingers, etc. I made a hanger out of 3" channel and secured it with a 2 " ratchet strap to the rotary unit. Then I could remove the RU with a come along. replacing the seals was just standard procedure. The hanger is still lying around somewhere in my stash.

  2. #2CAT Dillon2020-01-02 12:42

    The splined shaft in the rotary unit is no longer available from Caterpillar. The constant turning left and right when digging with the loader causes the splined shaft to get hammered to the point of failure. Then you will be up the proverbial creek. I would remove the hoe when not in use. The bare machine is more nimble, though in a perfect world a counterweight should then be fabricated for the hoe brackets. The weight of the hoe also causes premature failure of the rear track frame roller on each side.

  3. #3Welder Dave2020-01-02 13:55

    I got it all done several month's ago. A few years ago I had the swing motor repaired because it was leaking. Splined shaft was worn but built up my spray welding for around $300. Seals for vanes were still good and housing seals were available. Putting the swing motor back in would require more precision than removing it but looking at it came up with an easy solution. I bought 2 3' length's of 3/4" ready rod and cut them in half. Then I threaded them into the mounting blocks for the swing motor. I used nuts to pull the swing motor into place and then replaced the ready rod with the clamps and mounting bolts. I wish I would have thought of that when taking the swing motor off.