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Bobcat e80 hydraulic thumb cylinder pressure

Discussion in 'Compact Excavators' started by Tuckerdog, Mar 25, 2020.

  1. Tuckerdog

    Tuckerdog Member

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    I bought a new to me low hour Bobcat e80 to use around the house to stack some large rocks. The machine was set up with auxiliary hydraulics, but I had to buy an aftermarket thumb. I am lacking power in the thumb. The bucket overpowers it easily. Release pressure seems good, but it has now grabbing power at all. My Deere 310SJ grabs very well, but I can’t get it to where I am working. I keep looking for a valve to adjust the third valve, but can’t find anything. Any ideas would be greatly appreciated.
     
  2. Ronsii

    Ronsii Senior Member

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    Can you post pics of how it is plumbed? is there a valve switch for maybe using the aux. for a breaker???
     
  3. Tuckerdog

    Tuckerdog Member

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    I will tomorrow when I have some light. I kept eyeballing this, and tried some adjusting, but didn’t find it to make any difference in clamping force. That is mounted toward the base of the stick. It appears the auxiliary lines are plumbed to a hard line that is on the outside of the stick, and really don’t flow through that box, but that is all I could really find.
     

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  4. Tuckerdog

    Tuckerdog Member

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    I assume there is a relief valve somewhere, but I can’t find it.
     
  5. Ronsii

    Ronsii Senior Member

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  6. Tuckerdog

    Tuckerdog Member

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    That would explain why it didn’t help any...thank you for ruling that out for me. Any ideas on what to look for?
     
  7. Ronsii

    Ronsii Senior Member

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    I am not very familiar with the E80... is the thumb controlled by electrical switches on the sticks or floor like other bobcats?
     
  8. Tuckerdog

    Tuckerdog Member

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    It is a foot pedal.
     
  9. Ronsii

    Ronsii Senior Member

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    I believe the valve is at the foot pedal along with reliefs.... however I do not know this for a fact... hopefully someone else with direct experience will pop in and confirm it... otherwise I'd look under there...
     
  10. Tuckerdog

    Tuckerdog Member

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    Turn that knob 90 degrees clockwise, and you have two way flow. That is in the smaller hydraulic cover area next to the cab. Posting this in case someone else runs in to this in the future.
     

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