if the engine seems to run ok at all rpm's, the first place to look is at the bottom of your boat , check for barnicle growth or any kind of fouling.make sure its running on both cylinders, is compression good,100 psi. if everything checks out look at prop.
BOB R
January 2009
get another propeller to try
it has a rubber bush in it which sometimes slip ( like a clutch in a car ) when the engine is under maximum load
ANDREW CUFFLEY
January 2009
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