No spark at all when you ground the plug and kick the engine? Perhaps you should check the points (contacts) and see if there is current there. Do you have a multimeter? If not it is a useful instrument. When you turn the crankshaft (counterclockwise)the points should break open with the timing marks. With the multimeter set to measure voltage, hook the black lead to ground (engine block) and red to the moveable point arm (ignition switch "on"). When the points are closed you should get less than 1 volt measured. When they open you should get battery voltage, and the timing marks should align at this moment. If all is good here, then check further down the ignition circuit for a fault in the coils or the high tension plugwires or the plugs themselves for bridged or bad gap. Hope this helps and keep us posted.