john deere A magneto help

[caleb in pa]

my friend has a jd A and he recently got the magneto rebuilt and he asked me to come help put it on. i have minor experience with magnetos except on my jd B, the A and B are the same years-1939- both are hand start. any help on knowing which way to put it on would be nice. thanks caleb

 

[Paul from MI]

1. On the bench turn the impulse coupling until it snaps with the top terminal firing. Then turn the impulse coupling backwards until the drive lugs are horizontal with the mag itself vertical as it would be when installed.
2. Rotate the flywheel intil the "L.H. Impulse" mark on the flywheel is in line with the mark that is cast into the transmision housing(this will be at the 3 o'clock position facing the flywheel). The drive slot in the end of the governor shaft should now be horizontal.
3. Install the magneto and rotate it as far as it will go clockwise facing the magneto. Turn the flywheel one turn. You should now hear the impulse coupling clicking as you turn the flywheel. Turn the flywheel until the 'L.H. Impulse" mark is in line with the transmission mark. Rotate the magneto counter clockwise slowly until the impulse clicks. Tighten it in this position. Install the L.H. spark plug wire in the top terminal, R.H. in the bottom one. Double check timing by turning the flywheel, impulse should click just as the marks line up.

This should put you in time. Good luck,
Paul