Does the engine have a tendency to start just as the key is released from the "start" position sometimes? if so, you may not be getting full voltage to the coil during cranking. Check the voltage at the coil "+" terminal during cranking. It should be 9.5 volts, minimum. A bad ignition switch contact, or not having an ignition bypass lead from the starter solenoid to the coil could be starving the coil for voltage during cranking.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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