Johnson K50?

[bjensen64]

I have what think is (based on serial number 138563) a 1930 Johnson K50. From what little I’ve read, I should be able to simply look at the model/serial number on the ID plate on top of the flywheel. Problem is, the flywheel doesn’t have that ID plate, it has some other piece mounted on top. I’ve seen a pic or two of something like this. but don’t know what it really is since I don’t think it is part of a recoil.

How else can I ID this motor? Pics below (Fuel tank removed). You can barely make out "Sea Horse 12" from the fuel tank decal that has been painted over.

Whatever model it is, I’m looking for a carb since the one I have is broken after something fell against it.

What would be the fuel mixture?

As always, appreciate all info and part leads.

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[Anonymous]

What is the casting number on the crankcase on the other side of the motor in the picture? Mixture is 8 to 1, or 1 pint of oil to 1 gallon of gas.

[bjensen64]

A number right above the serial number reads 2783. Another number on the cylinder block reads 11-9.

[kees]

.
Based on what we see here, pretty sure a 1930 model
carb. is okee , probably no sparkplug cover on this model and you said it already
serial nr. also points to that year.
btw. odd part on the flywheel !
😮

[Doug Wilson]

looks a like the K50 that I have except the top of the flywheel not sure what that is. The one I have does not have a cover for the plugs either.
I used condensers from a 60’s Chevy had to tap a hole for each one then made small plates to cover them on the bottom of the mag plate. When you replace the plug wires cut the wire about 1" from the coil and solder there cover with shrink tube or liquid electrical tape. That way you do not risk getting the coil too hot and messing it up. They are great running motors takes a little getting used to the mag and carb not being linked. After you get it primed mine will usually start on the first pull the rest of the day. I am using lubriplate 105 in the lower unit and so far have not found water in it when grease changed last couple of years.

Doug

how is it motors multiply when the garage lights get
turned off?

[bjensen64]

A couple of more pics. I do have the spark plug cover but it has a crack. I also have a spare flywheel since this one has a crack in it.

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[Doug Wilson]

I am thinking the k50 plugs were on the side

Doug

how is it motors multiply when the garage lights get
turned off?

[garry-in-michigan]

They were – someone has swapped powerheads. The early K had a spark plug cover that was the mirror image of the muffler. That spark plug cover would take a beating because it sticks out farther than the motor rests on the fuel tank. . . 😮

[bjensen64]

Well, that would explain why the spark plug cover has a crack in it. 😕

I never confirmed it was a K50, just thought it might be due to serial number. What the heck is this? 🙄

[Mumbles]

It probably is a K 50 as it has the proper carb. The K 50, 65 and 70 motors used this carb with the horizontal barrel valve but the 65 and 70 motors had a control arm from the magneto to the barrel shaft to synchronize the carb opening with the magneto advance. The K 50 doesn’t have this feature so carb opening and mag advance was done seperately. K 50 spark plugs would have been on the port side and possibly exposed. Later KA’s had a side cover with a spring loaded trap door to access the plugs. In ’39 they went to the rearward pointing plugs and dealers were advised to change over to the later style block when rebuilding the earlier motors. It was probably easier and cheaper to buy the kit than having the old block bored and using oversize pistons and rings.

That flywheel is a stumper though. Possibly adapted from an electric start SE 50 or PE 60?

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