The subject is the 54 Jubilee from the thread below.
The previous owner converted it to 12v and added an electronic ignition system. It still starts and runs like a champ and I've been bushhogging with it maybe an hour a day on and off since I posted in the thread above.
Yesterday, it did something odd that I don't quite understand. I was at the far end of the 10 acre field bushogging some light weeds with the hog raised up and it started feeling like it was down slightly on power. I had my hood up to keep debris off the bushhog from going down my neck so once I took my hood down, I could hear that it was misfiring a little. I turned off the bushhog and headed back to the barn, which was around 8 acres away (lot is an acre wide and 10 deep). I got maybe halfway back to the barn and it started firing normally again and did so all of the way back to the barn until I parked it. The monsoons have started again so I won't have it out for a day or two now to see what it does.
All gauges work and were normal and did not move throughout, there was no sign of any smoke of any color at any time.
I saw a small stick had lodged itself between the distributor and the block by the coil wire so I pulled that out, coil wire may have been slightly loose but that didn't seem loose enough to be the problem.
It seems more possible that this was due to the fact that this was by far the longest I've used it since I bought it. I generally cut for an hour in the morning or evening when it's cool, and that's it for the day. Yesterday, I cut once in the morning and once around noon because rain was on the way and as mentioned, this is the far end of the field so I had to get back and forth both times.
Since there was no smoke or issues with the gauges that signaled a mechanical problem, I was thinking electrical. Working on other types of machines over the years, I've learned that electrical stuff tends to fail as it gets hot once it has some age to it. Since everything else in the ignition system should be new, that leaves the coil.
Referring to the thread above where it would not start, I have a resistor behind the dash so I probably have the original 6v coil? I assume there is a test for the coil windings but shouldn't I really just install a 12v coil and eliminate the resistor to make the entire system 12v?