This one is probably a keeper (7.5hp but only 41lb and air cooled cylinder w water cooled exhaust manifold) but I need to repair or replace the prop to get the most top end out of it. My blades are chipped and worn down about -15% from a battle w a trolling motor drive casing that unlocked and dropped right beside it just close enough to scrape the prop. I wish it woulda just snapped the shear pin!
Prolly gonna get some low temp aluminum welding rods and build the blades up +10% more than stock which should still be just within the skeg length and see what they do. The trick is keeping them balanced.
I have another one of these 7.5's in my folks' garage pending a rebuild too.