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Compression Test - high?

Discussion in '60-Series Wagons' started by RenegadeQ, Feb 28, 2007.

  1. RenegadeQ

    RenegadeQ

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    I did a compression test yesterday with all the plugs out and the engine hot.

    Results were

    155 psi
    160 psi
    150 psi
    150 psi
    145 psi
    150 psi

    Then I checked my manual and found 149 psi should be the top pressure. Any idea what would cause higher readings? I'm assuming my 150 readings should really be 149 psi.
     
  2. NocalFJ60

    NocalFJ60

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    The guage's accuracy could be a little off which would cause it. Also in New Orleans if you are below sea level in theory it would be higher.

    If it was ever rebuilt, it could be higher compression than stock. I would test 5 again and see if it come up some. Other than that I would say the engine is in good shape.
     
  3. agent orange

    agent orange

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    I wouldnt worry about having too much compression, you can run up to 200 on pump gas with aluminum heads and attention to quench. Consider yourself lucky.
     
  4. 2mbb

    2mbb SILVER Star

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    Those numbers look similar to mine (mine may be a little higher). I've got the original 2F with close to 200K miles. I wouldn't worry about it. 149 psig may be the lower limit to what is considered acceptable.
     
  5. brian

    brian SILVER Star

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    i've heard that carbon build up can raise it.

    std 149 psi
    limit 114 psi
     
  6. RenegadeQ

    RenegadeQ

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    Good. Then I'll assume my oil buring problem is coming from the valve guide seals. Thanks for the feedback. :cheers:
     
  7. Sherpa 60

    Sherpa 60

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    "All plugs out, engine hot "...and throttle held wide open???
     
  8. grant5127

    grant5127

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    true... and your #s are correct........
     
  9. grant5127

    grant5127

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    because heated gas expands.... every stroke of the cyl. over the guideline limit of the test procedure raises the pressure.........
     
  10. grant5127

    grant5127

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    a leak down test is a useful tool in oil consumption diagnoses.....
     
  11. FJ40Jim

    FJ40Jim The Cruiser Whisperer

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    The 81-later high compression engines will gauge at 165. The service manual specs are not updated to reflect this.