Any suggestions on why a Johnson outboard tends to slow down when exceed 3000 rpm?

Question

When I attempt to accelerate, motor slows down beyond 3000 rpm. When in neutral, it can be choked to 5000 rpm.

Answer 1

Clean carbs> Run fuel cleaner in the fuel system>If you keep trying to run it on the choke you will damage a piston from lack of gas & oil>

Answer 2

cheapest is filters

Answer 3

classic symptom of clogged hi speed jets -- choking makes it run better confirms the diagnosis.

heed 45 cal's warning -- you're heading for disaster running it lean like that.

only solution is a carb rebuild -- it's really not that hard, with some basic tools and a good service manual.