1987 Johnson 140 firing issues
 

I have 87' Johnson V4 that's in good condition. It has sat more than
usual over the past year or so and now I'm trying to get it going
again. I'm having a strange firing issue that I can't figure out.
When I first start it, it misses badly, but if I take a plug wire off,
put a screw driver in the wire and touch it to the block bolts, it
fires slowly at first but then bust right off. I can then put the wire
back on and it purs like a kitten. This works on any given plug wire,
so I can't narrow it to a paricular wire, plug, or coil. I have
changed the plugs and checked all of the connections, but can't seem to
find anything. Would this be a powerpack going out or something else?

Thanks for you help.