I recently purchased a used 1978 85hp johnson outboard (with boat) I replaced plugs water pump did carberator overhaul it ran fine however on its shakedown run I noticed an acute loss of horsepower on further investigation I discovered the left 2 cylenders were not firing it was the power pack after replacing it the engine will not run it backfires horribly out of the exaust and dies if I try to give it gas it just explodes out of the exhaust and dies I am puzzled it has only 85 to 90 pounds of compression the two formally dead cylinders being the weaker two I have started it at night to see if any wires or coils are shorting out and negative.
I only cleaned the top carb I am going to go ahead and replace the needle seat and float etc to see if that is the prob. any help in this matter would be greatly apreciated the gas is fresh I drained both tanks then filled both with a fresh 50-1 mix also new fuel pump. thanks.
I only cleaned the top carb I am going to go ahead and replace the needle seat and float etc to see if that is the prob. any help in this matter would be greatly apreciated the gas is fresh I drained both tanks then filled both with a fresh 50-1 mix also new fuel pump. thanks.
