My 6 volt 8N has never been a problem until recently. In the past few months I've had three separate occasions where it wouldn't start due to some sort of build-up on the points. The points look fine. There is no measurable change to the gap, but something on the surfaces prevents them from carrying current when closed. Run a file thru there and burnish them to a high polish and the engine fires right up.
Saturday was the first time this happened while the engine was running. We were digging a ditch with the backhoe and the engine suddenly just quit (like the key was turned off or ran out of gas). Checked fuel, plenty in the tank and the fuel bowl. Noticed a few rust flakes, probably be needing a new fuel tank at some point. Checked for spark, nothing. Wander back to the shop for a handful of tools and parts. Filed and polished the points, checked the gap, put the cap back on, and it fired right up.
I've tried two different sets of points and swapped the condenser out with another one. No change. Voltages are fine. Terminals are all clean. The ignition switch is good. This late 8N tractor does not use an ignition resistor. The weather has been far wetter than normal for the last couple years. Maybe I should try putting a thin bead of Permatex to seal the distributor cap? The next step may be to try a much older set of used points rather than new. The 12 volt 2N has continued to operate fine thru this entire time and the distributor hasn't been off in over a year. The front distributor does have gaskets, making me think that may be the problem with the side distributor engine. Anybody having a similar problem?