Another No Spark

I have been reading this thread because I have a 39 car with a 53 flathead and parked the car about 9 years ago. Running of course and now I cannot get spark. I changed the points condenser and the coil. I get 6 volts to the coil but no spark. I gave up and just had it towed to my mechanic who understands old cars. Hopefully he will get it running. Any advice from those of you out there would be appreciated. The coil I put in was bought from NAPA. Maybe a bad coil? The points and condenser were in my basement that I bought at a swap meet many years ago. They were delco new old stock. I am in the Milwaukee, Wi area.
 
Keep seeing references to 6 volts at the coil. The voltage at the coil should be around 3 to 4 volts, not 6 volts (with the points closed). That is what the ballast resistor is for, to drop the voltage to the coil.
 
Because my car had a transplant 53 flathead since I bought the car many years ago. The coil wire comes from the ignition switch directly to the coil. That gives the coil 6 volts and this is the way it has been for all these years. Will this create a no spark? remember it was this way when i drove the car to the storage. should the coil have a built in resistor? I think they do make them that way.
 
The voltage required at the coil depends on the coil, not the engine or engine year. If it is a coil designed for use with 6 volts it will work fine without a ballast resistor. That is determined by the internal primary resistance of the coil. The primary resistance should be something close to 2.0 ohms for it to work properly.

It is V/R = A, Voltage divided by the resistance (ohms) equals the Current. You want the current to be in the 3 to 3.5 A range. So for 6.3 volts that would require 1.8 ohms of primary coil resistance and 7.4 volts would require around 2.1 ohms of resistance. The current can be higher than 3.5A, but the higher it gets the shorter the life of the points.
 
Distributors work by providing ground to the coil via the contact points which are operated by the multipoint cam in the unit. If you have power to the coil but no spark at the plugs, it is likely one or both, in the older distributors is not making contact. We have also been seeing new point sets with defective insulators where the screw holds the brass strip that connects the point to the terminal.
 
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