A week or 2 ago, I mail-ordered an upgrade to the John Deere 316 lawnmower. The upgrade is intended to make a hotter and more consistent spark to the spark plugs. I have had some trouble starting the machine if it sat for a few days. With some research on the internet, I found this fix:
The upgrade is a small box filled with electronic gizmos that connect to the coil and to the points. This box takes all the current from flowing through the points. By not flowing such a high current through the points, they should (theoretically) last forever, and engine performance won't decrease. There is also a small red LED light on top of the module to assist in timing. Everytime the LED blinks, a pulse is sent to the spark plugs. In the case of this engine (180 degrees opposed), the spark plugs fire on both the compression and the exhaust stroke.
First, I had to find a place to mount the new box. I chose a place under the instrument panel - far away from the heat of the engine.
I also bought a new "hot" coil in addition to the module above. I had a hard time finding a location to mount the new coil, for it is a different shape than the old coil. I chose to mount it on the firewall above the air cleaner. Here is a picture of a little mount a machined out of aluminum to hold the new coil.
And finally, the coil is attached to the new bracket.
I made up some new spark plug wires with copper cored wire. The old wires were too short, and they were the carbon fiber wires good for noise suppression which is not needed in this case. Here you can see the new coil and wires fit nicely right over the air cleaner cover.
With the upgrade, I have noticed the engine starts up easier. It used to take quite a few seconds of cranking over the engine if it had sat for a few days. Now, it just starts right up at the first touch of the key. I'm happy with it so far, and the Boy is happy to get his lawnmower back for wagon rides.