[Hydratech®]

Hey T - what are the details? Year? Make? Model? Stock ignition? Aftermarket?

You must have positive voltage to one side of the ignition coil, with the negative on the other side of the coil being what is switched on and off to induce the production of a spark.

Grab a test light and see if you have positive power at one side of the coil when the key is in the on position. If you don't, then you'll have to chase down why. In some cases, you *could* use a FUSED temporary jumper wire setup to temporarily supply the missing 12v, though do this knowing that you could have other issues and may be playing with fire.

If you have a test light handy, disconnect the negative lead to the coil, connect the aligator clip end to the (+) terminal on the battery, test to make sure it lights up when you touch a ground, then connect the probe to the negative coil wire and have a helper crank the engine over. If the test light blinks, this means that you are getting the "negative flash" needed, which indicates that the ignition primary switching circuits ARE working (pickup, module, or points are ok). This is most likely not the case though, as you indicate that you did replace the coil...

Give us more info - pretend that we are sitting in a dark room + blindfolded, as this is essentially about the case!