Magneto Installation

(note: updated Oct. 11, 2011)

Result: Spark will occur and fire the left side spark plug (flywheel side) on the compression stroke when the LH Impulse marking on the flywheel passes the three o’clock position. Most models have a matching mark (or tab) on the crankcase, (or flywheel cover late A’s and B’s).

FLYWHEEL—–Turn the flywheel in the running direction (counter-clockwise) until the left side piston is coming up on compression, and facing the flywheel the “LH Impulse” is at three o’clock. Late A and B tractors with covered flywheel, the timing marks are at six o’clock under the center cover. If the flywheel is on the correct spline of the crankshaft; and the cam to crank and governor to cam gear is in time, the female drive notches in the magneto drive will be horizontal.

MAGNETO—–WICO X OR C… Turn the magneto drive coupling until the male drive lugs are horizontal. Install the magneto. Initially, rotate the magneto case clockwise (forward) against the governor housing as far as the slots will permit.

Again, slowly turn the flywheel in the running direction until the LH Impulse mark aligns at the 3 o’clock position. Next, slowly rotate the magneto case CCW (backward) until you hear the magneto impulse trip or “snap”. Tighten the magneto attaching bolts at this position.

ON WICO “X” or “C” The UPPER plug wire nipple is for the flywheel side (LH) spark plug, and the lower wire nipple is for the RH cylinder.

If the engine won’t start or backfires through the carburetor, the spark plug wires may be reversed.   If the engine runs with the spark plug wires reversed, the magneto is 180 out.   To have the lower wire to go to the RH cylinder, remove the mag and turn the drive coupling 1/2 turn and re-time.

Solid core spark plug wires are required with magnetos.  Spark plug gap should not exceed .030″

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