I have a 1995 Mercruiser Gen II 4.3LX. I was prepping the boat yesterday for it's initial use today. I was changing the thermostat and broke the spacer sleeve so I decided to run today without the thermostat installed. Everything was running fine, around 100 degrees on the temp guage. After about 90 minutes of running it started to "starve" for fuel. I couldn't get more than about 3000 rpm. We headed back to the launch and it seemed to clear up. On the way back to the loading ramp I slowly added throttle until it reached about 4300 rpm. It was running fine until I heard a metallic wrap. The sound is synchronized with ignition on one cylinder so I am guessing that I wrecked a lifter, push rod, and/or rocker arm ( I hope it is just a rocker arm but I have my doubts). The motor doesn't seem like it is missing and I have good oil pressure. I hope it isn't "short block" time....
