Home › Forum › Ask A Member › BIG old Johnson twin 20’s-30’s
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Tubs.
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September 17, 2017 at 2:54 am #65014
It SHOULD be a K-40 from the size – but I am no Johnson expert . . . 😕
September 17, 2017 at 11:36 am #65018Is the serial number stamped into the crankcase somewhere? It was stamped near the bottom of the crankcase on the smaller motors.
It would be a good way to see if the rope plate belongs to that motor.September 17, 2017 at 12:31 pm #65019The serial number IS stamped into the very bottom of the powerhead, and it is the same as on the rope plate.
Obviously I can’t measure it, but I can see no differences between my motor and this one:http://www.ahlstrandmarine.com/products … -1927.html
Weird.
Jim
I say "pardon me" a lot. I had a 20H, then raced open mod sleds.
September 17, 2017 at 12:55 pm #65021I think garry hit it on the head with K40.
Cannot explain the rope plate though.
September 17, 2017 at 8:42 pm #65053This might be a mix of parts. The gear foot looks like P-35 or later, buy the exhaust manifolds are P-30. The P-30 had smooth "runners" from the port to the round part of the casting. The P-35 got cooling fins. The prop looks big to me…bigger than a K. Could be a P-40 with older manifolds.
October 8, 2017 at 8:46 pm #65928Olde Pig ran today. Not very well, but it ran. Needs some love, but lotsa’ compression and a good hot spark. Looking at a K-35 I bought recently…..that’s what it is. I’d love to hear it’s story….and the non-existant model number explained. It’ll be at the Byron, MI swap meet next week.
Jim
I say "pardon me" a lot. I had a 20H, then raced open mod sleds.
October 9, 2017 at 12:31 am #65934It would have to be a K-40, not big enough to be a P-40 – REALLY BIG would be a TR-40 . . . 😆

October 11, 2017 at 12:30 am #66034Looks like my K-40 1928
October 11, 2017 at 12:41 am #66035what are the casting numbers on the cylinders? Looks like a K 40 but could be a P 40? 😉
October 11, 2017 at 10:01 pm #66078Where are the casting numbers on the cylinders? I’ve pretended to look on that and my legit K-35 and aren’t seeing any. Side by side pics-one is this goofy ‘Model 660’…the other is my very unmolested ‘survivor’ K-35. Other than the Model T Ford brake handle tiller and the replacement copper fuel line….to this idiot, they look the same. Pay no attention to the background….I have a real soft spot for 5 1/2 CD’s…
As always, thanks for any help!
Jim
I say "pardon me" a lot. I had a 20H, then raced open mod sleds.
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