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I have a 1953 3100 with original 216 (12V) that has been running great. A few days ago, while idling, the engine just quit....no misses or otherwise...it just quit. After checking a few things, I found that there is no spark coming from the coil. The resistor is good, the coil is good and the ignition switch is good. How would I check the regulator for proper operation. Everything that I have found checks the regulator with the engine running. The points and condenser are fairly new. I'm stuck...any help would be greatly appreciated!

No spark out of the coil is points not opening or closing. Maybe the points were not tightened down enough. The regulator would have no affect on the ignition system, it simply regulates the charge rate back to the battery. How did you check the coil? Are you getting power to the coil? (test light)

Check the hot wire going to the coil for voltage. No voltage could indicate an open wire somewhere. If you have voltage going through the coil, remove the distributor cap and check for voltage on the breaker arm with the points open. No voltage there indicates a bad wire from the coil to the distributor or a bad coil. If you have voltage that far, try opening and closing the points. Make sure you have the correct gap in your points and that they are not burned. Your coil should pop a spark every time you open the points. Once you narrow your trouble down, it won't be that hard to find.

OK....I have 13.04 volts at the resistor, coil hot wire, going in the distributor and at the open points.....I'm no mechanic, but shouldn't I have spark?

If the points are open, bridge something like a screw driver across them. Whenever you break the bridge, the coil should pop a spark. If it sparks then, look for something like moisture in your distributor cap. Whenever the engine, the condenser loads while the points are closed and then discharges when the points open and that is what causes the spark. If it does not spark when you bridge and break at the points, I would suspect a bad condenser or your breaker plate is not grounded.

First, make sure the distributor is turning. Not likely, but you could have a stripped timing gear. Pull the distributor cap and crank the engine- - - -the rotor should be turning as the engine cranks. While you're in there, be sure the points have at least some sort of gap. If the points are making and breaking, there should be a spark unless they're burned so badly they can't flow any current.
Jerry

OK....no spark when I bridge gap with screwdriver. No moisture in cap, but cleaned out anyway. Distibutor is turning. Took points out and cleaned with emory cloth and reinstalled same points. Engine started as usual, ran for about 10 minutes and quit like before. Won't start now. My problem is likely the points and not the condenser, right? How long do you normally get out of a set of points....these are fairly new, maybe 4-6 months with only weekend driving time.

If you're burning points that fast CHANGE THE CONDENSER! It's there to protect the points as they open, to prevent a big flash from the induced voltage as the coil magnetic field collapses. A 12 volt system can induce as much as 100 volts into the primary circuit as it's generating several thousand volts in the secondary winding to fire the spark plug. That flashes a big arc across the points as soon as they open if the condenser isn't doing its job. The condenser is supposed to shunt that voltage spike away from the points while they're getting far enough open not to arc. The condenser discharges itself in the time the points are opening and reclosing in a fraction of a second, but vitally important to good point life.
Jerry

Edit: if you're not running a ballast resistor in the primary circuit, that can and will burn the points in short order, also.
Jerry

Is the ballast resistor one in the same with the ceramic ignition resitor mounted on the firewall above the starter? If not, what is a ballast resistor and how do I add one in the primary circuit?

Yes, that's it. It reduces the voltage applied to the coil primary to about 9 volts during normal running. Be sure to check the voltage with the points closed if you do it with the engine not running, otherwise it will read 12, not 9. The best bet is to check voltage at the coil + terminal with the engine running. It should read 8 to 9 volts if everything is working right. During cranking, there is a bypass circuit from the starter that applies full battery voltage to the coil. That voltage just happens to be around 9.5-10 volts because of the starter load.
Jerry

After some more detailed checking, this is what I have.....With points open I have 12.94 volts going into resistor, 12.94 coming out of resistor, 12.94 into coil, 12.94 out of coil, 12.94 into distributor and nearly nothing at open point contact. With points closed I have 12.94 into resistor, 6.37 out of resistor, 6.37 into coil, .34 out of coil, .34 into distributor and nearly nothing at contacted points. I guess a condenser and points should fix the problem....just not sure about any type of underlying or secondary issue that may be causing condenser to fail. Thanks in advance for further help or comments.

I've seen condensers fail out of the box. Many times when you open the points manually with the ignition on, a bad condenser will create a flashy blue spark instead of a "snap" of a bright silver spark.