Herman,
Your FMJ was an aftermarket magneto made by FM for the 2-cyl JD. It is likely an FMJ2B6. There are no gears in the magneto, just a big rotor disk which has a piece of metal embedded in it, and as it passes by the brushes in the cap it picks up the spark for the proper outlet at the cap. Your component parameters sound fine, as far as they go. The magnet is Alnico, and rarely needs recharging (in my experience). The more likely problem is breakdown in the coil. Is it black in color, or the more modern orange one? If it is black, it likely is suffering from leakage due to poor insulation, with a resulting weak spark output. I look at them on a scope to determine the output, and it is not uncommon to have an age-related problem with the old coils.You might also take an eraser (back end of a "lead" pencil) and clean the rotor disk, and check that all three brushes in the cap are in place and in good condition. Also make sure that the screws holding the coil in place are tight and making good contact with the coil pole piece. In my opinion, FM finally got it right when they brought out the FMJ mag, but by then had lost the JD contract. The FMJ is often hotter than either a Wico C or XH, but was never offered as original equipment on a JD. I am currently running one on my GPWT. Post back with the color of the coil, and condition of the rotor and brushes.
|
