I have a Merc 150 XRi with a fraction of the #2 piston disintegrated from either a lean situation or simply failed from fatigue. Not certain the cause. Haven’t opened up the crank to see the oil gear condition. Fingers crossed the scoring is minimal.
Do you typically keep/replace the plastic oil gear on the crank or do you remove it completely and go premix? I have a 2000 210 2.5 V6 Sportjet which is very similar to your engine. Mine threw a rod on #6 and melted the piston. My gear looks fine, but I'm just wondering if I should keep it. I purchased the entire boat, trailer and engine for $1200 so if I screw it up, I don't care. I can buy a rebuilt powerhead worst case, but I would really appreciate your thoughts. I'm a subscriber and have seen all of your videos. The trilogy 2.5 Powerhead Rebuild I keep on as background music in my shop : )