I'm new to owning a boat and could use some help. The motor itself runs good but while cruising the rpms will shoot up and I'll loose speed. If I slow down completely and give it throttle it will go back to normal speed. This has happened a few times lastnight on the lake and the only thing I can think of is the propeller ? The motor is a 2001 merc 75hp 2 stroke on a 20ft pontoon.
