John Deere A/Timing Notes from Mr. Duane C. Larson

Does anyone have access to Mr. Duane C. Larson's notes for timing a John Deere A (49)? I recently came across a YouTube video where they were being used and looked to be very detailed if. Thanks in advance for any help.

"[b:654c4848f0][i:654c4848f0]timing a John Deere A (49)?[/i:654c4848f0][/b:654c4848f0]"

Reviewed the [b:654c4848f0]OPERATOR?S MANUAL No. OM-R2001R JOHN DEERE MODEL ?A? SERIES (SERIAL No. 648000 AND UP) TRACTOR[/b:654c4848f0] in the [b:654c4848f0]IGNITION SYSTEM[/b:654c4848f0] section under the [b:654c4848f0]Installing Magneto on Tractor[/b:654c4848f0] topic on pages 34-35.

"[i:654c4848f0]Installing the magneto after it has been removed from the tractor can be done easily as follows: First remove the spark plug on the flywheel side.



Place your finger over the hole and rotate the flywheel in the running direction until you feel a pressure of air in the cylinder. Continue turning the flywheel slowly until the punch mark stamped on the flywheel hub, lines with the ?V? grove on the flywheel guard.



In this position the slot in the coupling on the governor shaft will be horizontal.



Next secure a short piece of wire and insert one end in the upper terminal of the distributor cap on the magneto, bend the other end around within 1/8-inch of some metal part of the magneto.



Hold the magneto solidly in the same upright position as when mounted on the tractor.

Grip the driving lug on the impulse coupling firmly and turn the impulse slowly in a left-hand direction (counter-clockwise). Stop instantly when impulse trips and spark occurs between end of wire and magneto frame. When impulse trips, driving lugs on the magneto coupling will be in a horizontal position.

Replace magneto and gasket on the governor case, making sure the impulse coupling lugs engage slots on the governor drive coupling.



A gasket must be used between bolting flanges. After tightening the two cap screws firmly with fingers, rotate the top of the magneto toward front of tractor as far as possible. Then rotate the flywheel one complete turn and line the punch mark on flywheel hub exactly with the ?V? groove on the flywheel guard.



Now tap the top of the magneto toward the rear of the tractor a little at a time until the impulse trips.

Tighten the cap screw holding magneto to governor case and install spark plug cables. Left hand spark plug cable must be installed in upper distributor cap terminal.



[b:654c4848f0]Caution: Whenever adjustments are made on the tractor engine, remove the spark plug cables from spark plugs and battery ground cable to prevent accidental starting.[/b:654c4848f0][/i:654c4848f0]"

Hope this helps.