Re: 1970 Johnson 25hp no spark on top cylinder
Yes could be one of all of those, try cleaning and adjusting the points to .020 with a feeler gauge, inspect coils for cracks and deterioration. Check the end of the wire that is in the dead coil, remove 1/4 and rescrew into the coil, could be bad contact. If you are using plugs to test swap plugs, if you suspect a bad coil swap the coil, bad points-swap the points, bad condensor-swap the condensors- if you have one side that works and one that doesn't you can swap parts between the side that works to aid in troubleshooting as both sides are identical.
