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Jim, that’s an interesting engine. Was that a "one off" or did it
go into mass production?
Good advice on "over speeding" the Wisconsin. The mag does have
a kill button on it. I know my current mag isn’t ideal, having non-adjustable
spark advance, and spark in only one direction, etc., but I was
hoping to get the Wisconsin running while my uncle (who gave it to me)
is still walking this earth.
I could retard the mag by pulling the flywheel up, and setting the drive
gears "back" one tooth. Not sure what that equals in degrees of timing,
but both drive gear on the flywheel, and driven gear on the mag drive shaft,
have 20 teeth. Doing some math, which isn’t my favorite thing, I come
up with 18 degree’s retarded by setting the gears back one tooth.
Not sure if it would start retarded that much. Possible I could mess with
the points in the mag to retard it a "tad".
Plan "C" was to convert the Bendix mag to a distributor, using battery
and coil, but it still wouldn’t have any advance, so I’m in no hurry
for that plan. Not sure I can engineer a battery ignition with spark advance.
Thanks for the hep!
Make sure you have a kill switch hooked up to the magneto in case it over speeds. Slow turning 2 strokes are controlled primarily with timing. I would suggest that you start out with the timing 10-20 degrees retarded and advance as needed. You fuel mixer dosn’t appear to have a throttle control so it won’t be much help in trying to slow it down. The stem being sloppy shouldn’t be much trouble as long the valve is seating. Sounds like your spring will be fine since it’s opening. As Tubs stated pulling thru compression is the way to start it. Bumping against compression is more of a buzz coil battery ignition setup starting procedure. If planning on running on a boat you will need to be able to adjust timing while running. I would suggest finding a magneto that is adjustable, or converting it to a battery buzz coil type ignition system.
Below is a link to a engine I have, that by design of the make and break ignition system cannot be retarded past TDC. In order to run it without a load, the throttle in barely opened to keep it from overspeeding. Restricting the air this much, causes it to cycle multiple times between firing.
Jim
https://m.youtube.com/watch?v=EI0k5zaj4X0
Prepare to be boarded!
