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KX121-3 auto idle

Cummins ISB ยท 2017-06-22 04:55

Sometimes while working the excavator with auto idle on it will suddenly idle down. Then it won't rev up again unless I turn the AI off. There doesn't seem to be a pattern of when it does that except when its hot.

Replies5
  1. #1MikeVG2017-06-26 07:13

    Had the exact same situation with a friends Deere 35D. Started out with by trying the simplest fix and changed out the potentiometer although the original seemed to check out OK. Hope, that wasn't it. Ended up with replacing the controller module and the actuator - $2500 later! should have just done away with the AI and put in a throttle lever and cable like the earlier version 35's

  2. #2Cummins ISB2017-07-02 21:49

    It's not a big issue for me, so I won't be doing anything about it for now. Not for that much money!

  3. #3Tags2017-07-08 17:53

    I believe the auto idle unit is under the floor plate and can get surrounded by mud and dirt causing it to get stuck sometimes. It wouldn't be too hard to check that.

  4. #4Cummins ISB2017-07-08 19:23

    Thanks, I'll check that next time I have it home in the shop.

  5. #5JPSouth2017-07-19 11:34

    Why I own a '99 KX161- 2 . I'm not a Luddite or anything, and tend towards being an early adopter, but also fully embrace the KISS principle. $2500 buys me a nice new bucket, grapples for the skiddy, or 1/2 of a new set of hybrid tracks. A guy should not have to pony up that kind of coin to get his machine to idle up.