sea king low power

[willamkodiak]

i have a 1972 35hp. sea king. it's never had an abundnce of power in the 12 years i've owned it. but in the last few months it really has low power. any ideas? the prop is not dinged up or beat up. it has new plugs. could the timing be off. or should i check the compression? what should the compression be on this engine? the orginial owner said when it was newer it had a lot more power than it does now. thanks for any help or ideas