Re: 1970 60HP Evenrude!
You have to do some orderly, systematic troubleshooting. Fisrt make sure you have 12V (+/-) to the amplifier when cranking. If not, backtrack to find the problem.
Secondly, disconnect and remove the coil and unscrew the spark wire from the distributor cap. Then remount and connect the coil, and rig up a spark gap from the end of the spark wire. Crank engine. Do you have spark at the wire? If you do, everything is ok up to that point and you have a problem in the distributor cap.
If no spark, disconnect the black & white wire that runs between the amplifier and timer base. With key turned on, brush the amplifier-end wire terminal across a bare, grounded metal part. You should get a flurry of sparks across the spark wire gap. If you do, everything is ok up to that point, and trouble is in the distributor. If no spark, you have a bad coil or a bad amplifier. It is cheaper to try a new coil than to try a new amplifier.
OK, if you have determined that the trouble is in the distributor, it is time to remove the flywheel and distributor cap for a looksee. First thing is the breaker points. They should be immaculatly clean and gapped at exactly .009" at their widest opening. If the silver anti-reverse cutout ring is shot, replace it. If not shot, lubricate very sparingly with just a bit of EP grease. The tab on the anti-reverse terminal does NOT stick down through the loop in the spring!!!!
Lastly, inspect and clean the cap and rotor. Remove (unscrew) the spark plug wires and test them for continuity. Use a bit of grease in the caps when you reinstall them, per the manual.
By this time you should have located the problem.
EXTREMELY Important---When you reinstall the flywheel, make sure the tapers are clean and dry and use a torque wrench to tighten the nut to specs. 70-85 ft/lbs, if I remember correctly.
One other thing. If it still has the surface gap spark plugs, trash them and install Champion L77JC4 plugs gapped .035". Those motors never did run well on the surface gap plugs, and never will.
