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Cat 308 loose track, stuck tensioner...

Discussion in 'Excavators' started by Denys, Feb 27, 2021.

  1. Denys

    Denys Member

    Joined:
    Feb 13, 2021
    Messages:
    9
    Location:
    Vancouver
    Have Cat 308 with the loose track. Tried to pump the grease in with the high-pressure grease gun and she takes some grease and then stops(the idler will collapse if you push it with the bucket, so I assume the cylinder is fine), the excavator works in the mud constantly, what do you guys think, something gets stuck or what and how to fix it?????
     
  2. Tones

    Tones Senior Member

    Joined:
    Mar 15, 2009
    Messages:
    1,720
    Occupation:
    Ex land clearing contractor, part-time retired
    Location:
    Ubique
    How worn are the tracks? If they are the adjuster piston will come out to far and dump the grease. If the aren't to bad then a damaged seal will be the likely problem.
     
  3. Denys

    Denys Member

    Joined:
    Feb 13, 2021
    Messages:
    9
    Location:
    Vancouver
    thank you for your reply

    do you mean seal inside of the cylinder? they usually do not fail that often as I know
    I had a simular thing on cat 314, and the only thing which helped it is to heat the cylinder with the heat gun, that trick did not work on 308 though, I suppose the mechanism got a bunch of rust and mud in there, a good thing would be to put the b*****d in a heated shop, but company does not have one
     
  4. Tones

    Tones Senior Member

    Joined:
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    Occupation:
    Ex land clearing contractor, part-time retired
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    Ubique
    Lift the side of the machine thats leaking then grease the tensioner. Then you can see where the grease is leaking from but I'll bet you for one reason or another the seal is buggered. Those seals can be purchased from any decent bearing supplier and should be a viton seal.
     
    CM1995 likes this.
  5. John C.

    John C. Senior Member

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    Occupation:
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    I've seen plenty of the small excavators with the frozen track adjuster cylinders. I've had to try to pull plenty of them apart and they wouldn't come apart. Replacement was the only fix. Bust the track, the idler comes out the front of the track frame and the adjuster cylinder will either be in front of the spring or behind it. Sometimes the grease is coming through the wiper seal. Most of the times the cylinder is split. How stretched out is the track?