Thanks for the response, I'm not sure about vented prop. 16ft Tri Hull. I did put a different prop on for pulling skiers, and same intermittent. (this has been an ongoing problem since purchase) The guy that gave me the prop had knowledge of these engines and stated this was the correct prop...
1975 Johnson 3cyl loop charge 75hp 75ESLR75B
intermittent no/reduced power on accel.
Intermittently will not accelerate but to maybe 30% of potential, at other times runs fantastic, (although when running correctly, it would seem to me, it should respond faster to rapid...