[Patrick L.]

Just disable the primary circuit, such as, placing something plastic/cardboard etc between the points contact.
Place your ammeter across/around the starter cable.
Hit the starter and read the ammeter.
On 6v the draw should be under 450 amps. On 12v 250 amps.


It kinda sounds as if there is something drawing on the system which is not allowing enough electrons to the points. In other words the starter may be taking everything and when the starter is stopped spinning there is enough power to the points to allow the engine to start.

As mentioned, if 6v, make sure the battery leads are heavy enough to handle the load. The should be at least #1, however even bigger is 'more better'.