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pc 50-uu-2 final drive motor seized up.

Dwallace ยท 2020-04-27 06:49

I have a pc-50 uu-2. has two new final drive motors. yesterday I was working the machine and 1 motor seized and will not turn. acts like there is a brake holding it. any advice on where to start. thanks, Daniel

Replies3
  1. #1Vetech632020-04-27 07:11

    1. Drain the oil from the final drive and see if there is any metal in it. 2. Does it make noise of any kind when you try to move it? 3. Why does it have 2 new drive motors in the first place? From a previous failure? 4. Who did the drive motor replacement? 5. Machine serial number will be needed.

  2. #2John C.2020-04-27 10:47

    What your are trying to describe is a hydraulic drive motor turning is generally known as a final drive gear set. The failure mode you are describing is usually caused by something in the gear train breaking and the metal jamming the gears in place. To check this, do as Vetech63 suggests as there will be metal shards and grindings caught in the oil. The motor does have a brake inside of it but that is spring applied and hydraulically released when you send hydraulic oil to the motor to travel the machine. The failure mode for that brake system is to allow the track to turn on its own when parked on a steep hill. If you can take a photo of the final from the side of the machine so we will know the brand, someone here might be able to point you in the right direction as far as being able to fix the problem or replace the unit. Good Luck

  3. #3Dwallace2020-05-13 15:31

    resolved the problem. brakes were not releasing. blowed oring off piston. had to machine some off piston so it could move in housing. poor quality from manufacture. final drives.com is where they came from. tech did try his best. but they left me hanging with this defected drive a few months out of warranty with about 40 hours on it. now i'm expecting other side to fail about middle next job.