Take the spark plug out..Lay it on the cylinder...Turn the ignition on..Slowly turn the crankshaft counterclockwise until you see/hear a spark..Put a pencil mark on the sensor mount and another directly across on the hub .Measure The diameter of the hub close to the magnet..Multiply by .244.. Make another mark on the hub that distance clockwise from the first one..Put the piston on top dead center..Move the sensor so that the second mark on the hub is opposite the mark on the sensor.....This is 28 degrees...Slowly rotate the crank counterclockwise to confirm that the spark occurs at the first mark on the hub before the piston reaches the top....Easier than it sounds, try it a few times....
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