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Case 688 Swing Problem

Discussion in 'Excavators' started by u118824, Jul 14, 2019 at 4:26 PM.

  1. u118824

    u118824 New Member

    Joined:
    Sunday
    Messages:
    2
    Location:
    Northern MI
    A friend of mine has a 1988 Case 688. The problem is he can’t operate the swing with the engine at normal RPM or the swing function is lost. He has to shut the engine off, restart and then he’ll regain swing. All other hydraulic functions work fine at all rpm. He’s been nursing it along but it’s gotten to the point that swing only works at slightly above idle without losing it. He had a young Case tech look at it with no resolution.

    Any ideas on what the issue is? He’s changed the hydraulic filter. Thank you.
     
  2. Coy Lancaster

    Coy Lancaster Senior Member

    Joined:
    Dec 19, 2014
    Messages:
    766
    Occupation:
    service tech
    Location:
    Arkansas
    Sounds like the problem is in the swing valve. It is located beside the main control valve. It's been a number of years sense I've messed with one of those machines.
     
    Vetech63 likes this.
  3. u118824

    u118824 New Member

    Joined:
    Sunday
    Messages:
    2
    Location:
    Northern MI
    Thanks for the reply, I’ll pass your info along.
     
  4. old timer

    old timer Active Member

    Joined:
    Aug 31, 2010
    Messages:
    37
    Occupation:
    field mechanic
    Location:
    manitoba canada
    I think that is a Poclain made machine, Coy is right on about the swing valve, it's separate with the counter balance valves in the block. I had a 1088 with a swing problem like that, failed '0' rings in the counterbalance valves. Hope this helps
     
    Coy Lancaster likes this.