I have a 1972 Mercury 200(20hp). I replaced all the engine wires as they were decayed. I set the points to .020. Checked the condenser and it was reading .5 micro farads(not sure if that is good or not?) Motor started and ran in a trash can for about 5 minutes, it was a thing of beauty...
I just bought a little boat with a 20hp (200)mercury. Motor started and ran poorly first day I tried it(in my driveway). I replaced all the engine wiring as it was in bad shape. I cleanded and set the points to .020. Tried to start it again and it ran like a scalded dog...for a few minutes...