65 Dart wiring push start

This is how the start sequence works with that relay.

A couple of terms first:
Voltage is excited electrons or potential power.
Current is electrons flowing. Those flowing electrons are represented by the orange arrows.

0. With the key off no current is flowing out of the battery.
1. When the key is turned to start current flows through the key switch to the starter relay, through the neutral safety switch and back to the battery negative. Whenever the distributor points are closed a small current also flows through the coil.
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2. Power through the relay's bottom terminals internally connects the big stud to the solenoid terminal. Current flows from the battery to the starter's solenoid.
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3. The starter solenoid (inside the starter) closes and the starter draws battery battery power to spin it.
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The starter draws a lot of power.
Battery voltage will get pulled down during starting, but if it drops to 9 V its probably not going to start. Recharge the battery with a charger.
PS. If the battery is that low, do not jump it and use the alternator as a charger unless you are desperate. If you must do this, keep the engine rpms as low as possible to keep charging rate down.