Franken-A

Home › Forum › Ask A Member › Franken-A

Viewing 6 posts - 1 through 6 (of 6 total)
  • Author
    Posts
  • April 21, 2020 at 3:06 pm #200699
    need2fish
    Participant

      I have what I believe is an early Johnson Model A and I’m hoping to get some help to determine which model and year it is, so I can mate it to the correct rope sheave, tiller, muffler, flywheel and magneto plate.

      It’s been 15 years since I purchased it so I remember nothing about its story. I all I know for sure is that it either has to run and stay with the 20 or so that I plan to keep, or go with the 110 that won’t be making the cut.

      1) I don’t remember if I bought it with a rope sheave/flywheel/mag plate or not, meaning I have to know what I’m looking for in the dozen or so Johnson magnetos, flywheels and rope sheaves that could belong with it.
      2) The muffler is missing. Again, I could have it somewhere, but I don’t know what I’m looking for.
      3) It came with a semi-circular tiller support, bolted in place of the angular tubes that protrude from the front of the jugs (which in turn is where the tiller arm is attached). Is this a field engineering job or did the semi circular tiller support come as an accessory ? It’s made from stamped aluminum
      4) The armature plate with the fancy cutoff switch could be a candidate, but a stop-tab on the underside has been ground off, and the spark advance lever contacts the carb throttle when the throttle is in the S position.
      5) The tank filler has a short “snout”, whereas some of the A’s I’ve seen have a long one.
      6) There is a steel bar replacing the transom clamp pads. Another field engineering mod ?

      Any thoughts you have would truly be appreciated.

      Ken

      20200421_125436s

      20200421_125555s

      20200421_125638s

      • This topic was modified 4 years ago by need2fish.
      • This topic was modified 4 years ago by Mumbles.
      April 24, 2020 at 12:07 am #200922
      pm-t2
      Participant

        Canada Member - 2 Years

        Look on the underside of the powerhead. Check the flanges where the cylinder casting mates up with the crankcase. There should be some numbers stamped into the crankcase flange one one side or the other. Most likely a five-digit number, but you’ll have to clean it off to be able to read it well. Report that number and we can determine the vintage so you can set about looking for the correct parts. I’m betting its in t he 1924-26 range.

        In the mean time – what I can tell you in response to some of your questions’

        1). The semi-circular tiller attachment was never put on there by the factory nor was it an authentic accessory – thus, its home made.
        2). Short filler spout likely correct if the vintage turns out to be in the 24-26 range as I suggested, the longer filler neck was on a later A series motor with aluminum lower unit
        3). Yes, the steel bar for the transom pads is another field modification not sanctioned or provided by the OEM.
        4). The timer plate with the smaller aluminum handle and the red Bakelite button on it is most likely the correct one for this motor.

        Hope this helps.

        Best,
        PM T2

        April 24, 2020 at 7:14 am #200925
        stanley
        Participant

          US Member - 2 Years

          In addition to the above,the entire transom bracket appears to be a transplant,the manifolds are missing,and there is something weird going on with the way the gas tank is mounted.The gas tank does look like a 1924,but cap is not.

          April 24, 2020 at 9:28 am #200942
          RICK EICHRODT
          Participant

            US Member - 2 Years

            It appears that someone drafted a Johnson A powerhead on a Johnson F-70 type tower and foot. Just my opinion as I have both motors and the clamp brackets, tower and foot appear to be an F.

            Rick

            April 26, 2020 at 8:58 pm #201135
            need2fish
            Participant

              Hi – the numbers on the lower crankcase flange are either 13-184 or 73-184.

              Neither of the armature plates in the pictures will work. They sit too low on the upper crankshaft journal area and the lower part of the plate hits the crankcase and / or carburetor. If someone can post a pic of the underside of the correct armature plate, then I can go dig in my parts shelves.

              May 29, 2020 at 10:05 pm #204403
              need2fish
              Participant

                I’m just getting back to this project. The serial # is 43128, which puts in the latter part of ’26. I have an AZ-35 powerhead and another opposed A (haven’t got to degreasing them so I can find other markings).

                The strangest thing is, the Franken-A’s water tubes are all backwards. Where my other 2 opposed A’s have the water line from the front of the leg go to the bottom of the jugs, the Franken-A has its front water lines going to the top. The lines are all un-plated (painted?) copper so clearly they’ve been replaced; have you seen this on other engines ?

                The magneto that you’ve ID’d as the likely one that mates with the engine is a dud. The other one I have has a fat, crackling spark on both leads, so I may have to do some mag parts swapping.

                What was the from-the-factory compression number for this motor ?… It’s at 50 — no idea when it was last run but i’m sure the cylinders are very dry. My J-25 runs quite well @ 50 — a little rough idling and slow to accelerate, but then so am I and it’s got 30 years on me. 😉

              • Author
                Posts
              Viewing 6 posts - 1 through 6 (of 6 total)
              • You must be logged in to reply to this topic.