I have a 1994 75 HP Mercury Outboard on a 17.5' Alumaweld boat. Last year the motor ran great and was getting above 5000 RPMs easy. When I took the boat out last week, the engine would run fine but would only achieve around 3500 RPMs at full throttle and just has no power. It seems to run fine until it hits around 3000 RPMs, then it seems to bogg down even though the motor is screaming. I replaced the 3 spark plugs, replaced the inline fuel filter on the motor, replaced the gas and put carb cleaner in the gas, but has not gotten better. I also made sure that the fuel tank is breathing and everything seems to be fine. I am wondering if one of the cylinders is not functioning properly. I read that you could pull the spark plug cable while the engine is running to see if there is a noticeable decline in RPM's to determine if or which cylinder may not be working but have not tried this yet. I'm no outboard mechanic but have some outboard experience and am trying to do everything I can do myself before I bring it to a mechanic. What and how should I check next?
Any suggestions/help would be greatly appreciated.
Thanks,
J
Any suggestions/help would be greatly appreciated.
Thanks,
J