Last symptoms are lack of potential speed. Boat should run 34 but is topping out at 30. Jet foot is in prime condition and setting. Weeks ago when issues started. it was running rough at about 1200 rpms, so I changed plugs, no help. Did a carbon clean with yamaha ring free at 2 oz to 10 gallon. It seemingly got much better, but a few miles into that tank, I was on plane at 34, came off plane to thread some rapids and the motor started wobbling as if I lost a cylinder. Got it home, changed inline fuel filter, the big one. No water at all. Drained the VST, no water at all. Checked compression, all were 150+ and about the same. Took it back to the lake, did a pull one at a time plug test. No specific cylinder differences. Boat cleared up and started running good. But would only go 29? After checking it over, I realized it was making oil. Whether from last time out or over the last few times out, I don't know. I drained out 7 quarts of what should be 5. Googled how this happens. Thermostat was full of trash. Motor never was hot. Was likely stuck open. Changed thermostat, Changed plugs, changed oil and filter, changed out injectors with a cheap renewed injector after spray checking them and my pulled injectors. All seemingly were equal so I installed the renewed one's because their inner filter was new. No change. Still 29 mph. I'm beginning to wonder if, the speed issue could be that all else issues have been solved but, the change from a 20 micron filter to a 10 micron is starving the fuel pressure system??? Help, I want my speed back. I do need to go out and see if running it this weekend has caused it to make oil. I will report back. EDIT, oil good
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