I have a 93 mercruiser 4.3 Alpha Gen2 S#0D843639. This past weekend was my first time out this season. The boat ran excellent all day saturday. Was thinking it was going to be a good season. Went out Sunday for some more watersports on the same tank of gas. At first I noticed a slight pulse in the engine RPM at WOT once planed out. Made a note of it and continued. After a few runs, all of a sudden we couldnt even plane out anymore. I had to leave to come back home for the week so I didnt get a chance to look at anything. Looking for some ideas on where to start looking. Thanks