Please describe your symptoms a little more accurately. There's a world of difference between "won't crank" (engine doesn't turn over) and "won't start" (engine turns over but fails to fire up and run.) The diagnostic procedure is entirely different for these two conditions. I'm guessing you mean "won't crank" but that's just an assumption without evidence. "No crank" is usually caused by worn out starter brushes which doesn't let the pull-in winding in the solenoid find a ground so it can engage the starter drive and make the starter armature spin. The next time it happens, take a small ball peen hammer, lug wrench, or other blunt instrument and tap the starter housing. That will seat the brushes temporarily and let you fire up. Then go home, pull the starter, and change the brushes.

Changing the solenoid won't help - - - -it's not the problem. You got lucky and didn't ruin your alternator this time - - - -please don't EVER take a battery cable off while the engine is running again. It's a shade tree mechanic trick that causes huge voltage spikes and usually blows out alternator diodes or solid state voltage regulators.
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!
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