Hey Ray
Member
I have 8.1's in a 1997 330 EC. Engines were installed in 2014 and have about 200 hrs on them. Took her out yesterday and it ran rough when attempting to get up to cruising speed and wouldn't get close to expected MPH at cruising speed of 3400 - 3600 RPM. Usually can run at 25 - 30 MPH in that range depending on tide, but yesterday could barely get it to 20 MPH. Seemed like it wasn't getting up on plane. Felt a slight vibration in my feet at the helm, but nothing alarming. When I got back to the dock I pushed it up to 3000 RPM in neutral and engine's sounded very smooth and strong. Beginning of last summer did the whole Cool Fuel filter replacement and rail/injector replacement/cleaning, and at end of last summer had struts replaced and shafts realigned. Also just had bottom cleaned before this last ride. Any ideas?