I am having an issue with my motor SX250TURV that I need some direction on. I have read many posts before posting this, but I feel that I need some more help. Motor has run almost problem free for the last 3 years. I stay on top of maintenance. Friday before last went out and the motor ran flawlessly. Last Friday it did not run well. It sounds labored and seems down on planing power. It will not rev above 4300 RPM. At 65% throttle it is at 4300 RPM adding more throttle makes the motor louder, but will not yield any more power.
4 trips ago as preventative maintenance I replaced all 3 LP pumps, Cleaned VST filter, changed plugs, remote water separator filter, engine water separator, lower unit oil, tilt/trim oil. It ran fine before and after I did those items.
After the problem I replaced filters again. I also ran it with a fuel pressure gauge and it stays at 37 PSI at idle, plane, load, etc. I also tried (unscientific I know) removing the spark plug wires while on plane because I thought that maybe it was running on 5 cylinders. It is running on all 6. I am not sure where to go from here. This problem started suddenly and there were no issues before. I am scared that it is running lean, so I put some oil in the fuel tank to increase the ratio.
It is also worth noting that I only use non-ethanol fuel and that the fuel is fresh.
4 trips ago as preventative maintenance I replaced all 3 LP pumps, Cleaned VST filter, changed plugs, remote water separator filter, engine water separator, lower unit oil, tilt/trim oil. It ran fine before and after I did those items.
After the problem I replaced filters again. I also ran it with a fuel pressure gauge and it stays at 37 PSI at idle, plane, load, etc. I also tried (unscientific I know) removing the spark plug wires while on plane because I thought that maybe it was running on 5 cylinders. It is running on all 6. I am not sure where to go from here. This problem started suddenly and there were no issues before. I am scared that it is running lean, so I put some oil in the fuel tank to increase the ratio.
It is also worth noting that I only use non-ethanol fuel and that the fuel is fresh.
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