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JD 690E-LC Swing Motor/Brake Hyd. Leak?

LOFAYTX ยท 2015-12-16 21:58

I finally got the JD 690 E-LC home. The hyd. leak looks like it's coming out of the bottom of the swing gear box. the seal is out. What is most likely to be the source of the hyd. oil? The swing motor seal or the swing brake seals ?

Replies5
  1. #1LOFAYTX2015-12-16 22:26

    When I pulled the inspection cover plug in front of the rotary manifold it had 1-1/2" of grease diluted with hyd. oil in it.

  2. #2mikebramel2015-12-16 23:03

    The hydraulic motor may be pushing oil out of its shaft seal into the reduction box, overfilling, and causing it to leak? Or they have a common seal on the bottom. The bearings may be out or just the seal

  3. #3LOFAYTX2015-12-17 00:19

    I am going to dig into it more this weekend!

  4. #4LOFAYTX2015-12-17 21:19

    Do you know how the swing motor brake works? Can it cause a Hyd. leak?

  5. #5lantraxco2015-12-17 21:56

    The brake is built into the reduction gear and yes, it has piston seals so if they leak, the gearbox fills up and then oil pushes out wherever it can.