7.5 compression

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  • June 2, 2021 at 5:24 pm #239402
    james hobson
    Participant

      Question I did a compression check on my 7.5 evinrude I believe a 1956 I am getting 70 on top cylinder and 72 on bottom cylinder is this enough to run good and also idle or give up on motor,thanks

      June 2, 2021 at 5:50 pm #239403
      crosbyman
      Participant

        Canada Member

        try it ……….if it runs good keep it regardless of what it should be psi wise

        most of my bigger…. newer 9.5 are all around 65-75 and run fine. just run a good decarb product and enjoy it.

        Joining AOMCI has priviledges 🙂

        June 3, 2021 at 5:41 am #239416
        fleetwin
        Participant

          US Member

          These are low compression motors, so those readings sound normal to me….

          June 3, 2021 at 9:29 am #239429
          james hobson
          Participant

            Thanks guys, is that enough compression to idle.

            June 3, 2021 at 11:57 am #239447
            crosbyman
            Participant

              Canada Member

              very hypothetical question …just run it

              it is 65 years old with unknown TLC….but they are good motors. have you not tried it ???

              70s sounds fine with me. and both cyl look pretty much equal which is a good sign

              if the pressure tank leaks you need a good tank or convert to pump (easy)

              Joining AOMCI has priviledges 🙂

              • This reply was modified 4 years, 5 months ago by crosbyman.
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