My Grandfather ran a boat rental business when I was a kid. Put lots of then on the back of 14’rowboats. My QD 15 would walk away from them all day long. The 6 HP of the period were damn near as fast on those boats when lightly loaded. The 9.5 engines ran fine & were a delight to carry & mount on boats. Performance wise in my observation they seemed more like the old 7.5 than the 10. The 6 performed more like the earlier 7.5s.
Check for loose/broken motor mounts and make sure the gearcase lube looks OK. Try to lower the gearcase a little if the owner will let you. If all this checks out (along with other normal inspections), $50-60 seems like a good gamble.
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