A light MIST of fuel?-----Post actual compression value here.-----What type of fuel pump ( part # ) is on this motor?-----How did the motor run for you last season?
The wonderful " Magflash " ignition system came out on the 1971 model 50 HP .-----The 3 cylinders used it starting in 1972 .---The 4 cylinder in 1973.----It never used a " wasted spark " on any of them.-----Parts / pieces changed over the years , but not the theory of operation did not.
Automotive engines are rarely asked to perform at full throttle / maximum power output for long periods of time.----The outboard is also subjected to " wave action " on the boat.----That can put high loads on the oil film between parts.
A car engine may be capable of 280 HP.-----But it does not need near that output to move a car on a level road.----Put that car in neutral at 50 MPH and see how far it coasts.----Now try that with the boat.
Rectifier is not needed to make the spark.---The 12 volt battery is NOT involved in making the spark.-----The FAST spinning flywheel magneto generates spark.----First load test the battery.----Then inspect the starter motor.----Compression should be around 120 PSI +