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Final Drive?

cat 302 ยท 2022-01-22 00:39

Hello Folks I have a 1993 320L CAT. One final drive is slower then the other. Right hand side only going forward it was doing it before and then stopped and now it has returned. It almost sounds like a hissing sound or something is not opening all the way. The Machine is getting up to around 10000hrs and I was told the hydraulic pump may start to fail around now. However because it is only doing this in That one direction I am not sure.

Replies8
  1. #1Nige2022-01-22 05:13

    Have you re-sealed the centre swivel since you had the machine.? That would problaby be the first place to start on a machine of this age, the seals will likely have gone hard and probably fallen apart by now. Also you could check the flow from the travel motor case drain hoses and compare the LH & RH side flow to identify if the problem is in the motor. A Serial Number always helps when locating Part Numbers, etc. Especially for something as common as a 320 where there are probably 50 different variations.

  2. #2cat 3022022-01-23 04:03

    9kk00748 is the number for the machine.

  3. #3Nige2022-01-23 04:35

    On a machine the age of yours built July 1993 this is the first thing I would suspect. It has a load of seals (#7 & 8) inside that keep the oil in the different travel motor, brake, etc, circuits apart from one another. These seals go hard and crack over time and can allow the oil flow from one circuit to go into another. Personally this is the first place I would start if you do not have confirmation of a recent re-seal.

  4. #4cat 3022022-01-23 13:15

    When it first started happening I replaced the seals. It did not make a difference. It seems to come and go a bit almost like something blocked or not opening all the way.

  5. #5cat 3022022-01-23 13:17

    This only happens on the right hand track and only moving forward.

  6. #6Mobiltech2022-01-23 14:14

    Sounds like a relief valve problem in the counterbalance valve on the back of the drive motor. You could try swapping relief valves to see if the direction of the problem changes.

  7. #7cat 3022022-01-23 21:27

    Thanks I will check that out. It went away before I was climbing a steep hill working it hard and it just started working but then went back to being slow. Makes a sound like when your only on the pedals half way. would anyone happen to have a diagram of the relief valve? Thanks

  8. #8cat 3022022-02-06 00:54

    Anyone know a good place to buy used parts in Canada