I have a 1985 20 HP Mariner (A146190). This motor ran great last year until I lost spark in one cylinder. I replaced the CDI box, plugs, coils, and wires. Both cylinders have ample compression around 120 and over 1/2" of spark. If the motor sits for while, it will fire as soon as I touch the key and then just crank. The top cylinder is dry and the lower plug will be wet. I am lost at this point. The primer diaphragm had a hole in it. So, it hs been replaced. The carb has been apart and nothing is stuck. Also, even though the gas in the tank is brand new, the gas on the lower plug smells old. I reset all of the carb settings back to exactly where they were. If I have the warm up lever in the full throttle position, it will act like it almost wants to start. Please ask me any questions you have in order for me to help better describe this problem.
