[Purdy Swoft]

Probably an oil filled coil that had leaked some of the cooling oil or the upper windings overheated and burned out because the coil was mounted in the normal model A fashion with the wire connections at the bottom . Oil filled coils are normally or should be mounted with the tower and wire connections pointing upward. I either run original solid tar filled or performance epoxy filled coils on my model A's. Oil filled coils don't usually hold up all that long when used on model A's , mounted in the normal model A way .