my tach has not been working very well. a friend says that it might be running off the coil. i replaced my trailing side with another used one and took it for a spin but the same problems came up. could it be something else? could this be the reason for my hard starts?

 

Idle the engine and pull the trail sparkplug wire out of the coil a eigth inch or so. If you see no spark, the tach is not working because the trail coil isn't working.

If both trail sparkplug wires spark, the problem lies elsewhere. Like at the tach or the wiring b/t the trail coil and the tach.