Home Forum Ask A Member 1957 johnson 18hp fuel mixture

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  • #262929
    mike n
    Participant

      US Member

      hello, i’ve been running this engine on 24:1 mixture with tcw3 2stroke oil. does anyone recommend something different. thanks

      mn

      #262930
      dave-bernard
      Participant

        US Member

        16-1

        #262938
        Sams Outboard
        Participant

          I run 16:1 I believe that’s what they are from the factory aswell

          #262940
          bobw
          Participant

            US Member

            I run all of my mid 1950s motors, including my 1957 18hp at 16:1.   Oil is cheap compared to replacement parts.

            Bob

            1937 Champion D2C Deluxe Lite Twin
            1954 Johnson CD-11
            1957 Evinrude Fastwin 18
            1958 Johnson QD-19
            1958 Johnson FD-12
            1959 Johnson QD-20

            “Every 20 minute job is only a broken bolt away from a 3-day project.”
            "Every time you remove a broken or seized bolt an angel gets his wings."

            #262943
            johnny
            Participant

              US Member

              The instructions say to mix 1 quart of oil to a six gallon tank of gas and for smaller quantities mix it 16:1. One quart to six gallons of gas is 24:1 I run all my 1950s OMC motors with a 24:1 mixture.

              #262964
              bobw
              Participant

                US Member

                Here’s a copy of the tune-up data from a Johnson Condensed Service sheet, including recommended oil ratios, that I’ve always gone by.   Evinrude wouldn’t be any different.   There’s always a debate on the gas-oil ratio topic, but on any motor with bushings instead of bearings, I’ll run 16:1.

                Screen-Shot-2022-07-14-at-10.53.43-PM

                Bob

                1937 Champion D2C Deluxe Lite Twin
                1954 Johnson CD-11
                1957 Evinrude Fastwin 18
                1958 Johnson QD-19
                1958 Johnson FD-12
                1959 Johnson QD-20

                “Every 20 minute job is only a broken bolt away from a 3-day project.”
                "Every time you remove a broken or seized bolt an angel gets his wings."

                #262967
                bobw
                Participant

                  US Member

                  OK, digging a little deeper in my files, I found this later version of an Evinrude oiling chart that indicates 24:1 is OK for a 1957 Fastwin.   Don’t know how/why/when OMC might have changed this specification, but I’ll continue with 16:1.

                  Evinrude-Oil-Mix-Chart

                  Bob

                  1937 Champion D2C Deluxe Lite Twin
                  1954 Johnson CD-11
                  1957 Evinrude Fastwin 18
                  1958 Johnson QD-19
                  1958 Johnson FD-12
                  1959 Johnson QD-20

                  “Every 20 minute job is only a broken bolt away from a 3-day project.”
                  "Every time you remove a broken or seized bolt an angel gets his wings."

                  #262975
                  mike n
                  Participant

                    US Member

                    Thank you all for the input.  I know this has been a debate for quite a while. Just wanted some info.Going to run the beans out of it next week. Think I’ll try 16:1

                    mn

                    #262989
                    elgin2
                    Participant

                      US Member

                      I have heard that if they used a pressure tank use 24:1.

                      #262991
                      duralark
                      Participant

                        Hi Bob W — also happens to be my name. FWIW, friends and I in Michigan are all running 32:1 in all of our Johnsons and Evinrudes; 1956 Lark and Javelin 30hp, 1958 Lark 35hp, various smaller motors from 1956-58, Using TCW-3 spec oil. Less smoke and no lube-related problems in hundreds of hours at this ratio, and less oil in the lake too, of course.

                        I need help with a different issue. My 1958 7-1/2 Johnson, AD-12, has been hard to start for a couple of seasons, and began stalling when running at about shifting speed. It would stop suddenly, no signs of being rich or lean, no one-cylinder miss, just sudden death. And a rowboat ride home. I had rebuilt the carb (including a new float) when I got the motor a few years ago and it ran well until it started stranding me last year. Now it’s unusable.

                        I went through the carb again, everything looks as clean and beautiful as it did before. The sediment bowl and fuel bowl fill normally, inlet needle does not leak. But twenty pulls later, with choke on and throttle at start setting — she never popped once, and the plugs are completely dry. I took reed plate off, all looks good to me; but it’s as if fuel is not being drawn from bowl when cranking. But the motor runs fine, from idle to full throttle, when it does run. I’, looking through the carb again, hoping to find some clogged passage or something, but all looks great. Any ideas? I have started it with starting fluid a few times, after which it runs fine until it decides I need more rowing exercise. Argh.

                        Any advice appreciated,

                        Bob / Duralark

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