I did continuity tests and all the e unit contact fingers are making perfect contact with the drum no resistance and all wires are intact. As i cycle through the e unit steps I measure transformer voltage at the brushes and the field is energized at positions 1 and 5. The brushes are floating on the armature freely and are transmitting voltage to the commutator. Wiring is correct.
I polished the commutator with crocus cloth and now wonder if somehow this damaged the armature or if it was bad to begin with although the engine did run in reverse only at one point. I measure 2 ohms between commutator sections an 20 ohms between the armature shaft and each section which is consistent with a working engine (wires not disconnected) so there are no apparent shorts.
Everything looks fine and it won't run. I must be missing something but I have no idea what.
