Spark Problem on my motor

[bassbooger]

Alright fellas, I need a little bit of help if anyone can offer up some expertise. My motor is crapping out on me. I have a 1973 Johnson 20hp tiller handle with manual start. Here is the issue. I gave this thing a tune-up back in November and has been running fine all winter. The other day I take it out and it fires up just fine as usual. Go to turn down the throttle from cranking and it dies, which really puzzles me because it hasn't done this in 2 years. Motor would not crank again. I got it home and checked the plugs, even changed them both out without any success. Pulled both plugs to check for spark and neither one are getting spark all of the time. They will get spark on every 4th or 5th pull and that is it. Any other time, there is no spark. I checked the wires and noticed that my ground wire that ground the armature plate to the motor had broken loose. I reconnected it, but didn't help. Would this thing breaking cause my condensors or coils to burn out? I plan on doing a tune up and changing my plug wires. If anyone can think of anything else I can do, or what I could possibly check before i go spend money on this stuff for nother, then please feel free to help me out. Thanks!!