1951 Johnson QD12 bypass flap

Home › Forum › Ask A Member › 1951 Johnson QD12 bypass flap

Viewing 3 posts - 1 through 3 (of 3 total)
  • Author
    Posts
  • January 17, 2018 at 3:19 am #9020
    bob-d
    Participant

      US Member

      Does anyone know what this flap with the spring closure is for?
      It looks like a exhaust pressure release flap, but it vents off the driveshaft tube. I don’t believe there is any exhaust pressure in that tube?
      Bob D

      Attachments:

      January 17, 2018 at 11:56 am #69802
      frankr
      Participant

        US Member

        Good question. Putting on the ol’ thinking cap, I’m thinking the gearshift linkage opens the flap, allowing exhaust to ENTER the drive shaft tube, where it escapes to the outside through vents in the tube. (Right??)

        January 17, 2018 at 3:26 pm #69808
        bob-d
        Participant

          US Member

          Bingo….your right Frank.
          The C shape connector the attaches the top shift rod to the lower unit, hits the top of the lever, and opens the flap. Never thought of that.
          The early QD’s definitely has some unusual design features.
          Thanks for figuring it out.
          Bob D

        • Author
          Posts
        Viewing 3 posts - 1 through 3 (of 3 total)
        • You must be logged in to reply to this topic.