simple tester homemade out of wood, coathanger wire, alligator clip . to make cut out the circle in wood and solder on the ends you can make it different the idea is to be able to see the spark jump from one pointed tip to the other. (easier if you remove the sparkplug to make engine easier to spin over) the tips are adjustable to see how far spark will jump don't see a spark then be brave hold on to it you will know real quickly if there's any fire in the system.





here is another view make it to work for you as this is only one way of doing it.