250 Yamaha EFI Maintenance Tip

Salinity Now

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Ive been chasing a high RPM hesitation gremlin on my port engine for over a year now, between work schedule and trouble shooting the sometimes sparadic problem its been a LONG time coming. I did the typical recommendations, VST, LP pumps, motor mounted filter, did a HP gauge test at all RPMs, changed fuel lines looking for air leaks, cleaned electrical connections, changed main fuses, changed VST again, even pulled all the injectors and had them cleaned, cleaned o2 sensor, then replaced with a new one!! (the list got to be too much after awhile)

All the while not knowing about High Pressure Regulator Screen, a simple little screen on top of the VST tank, tight fit to get to, but a simple fix. IF you are doing routine maintenance and cleaning VST, CHECK THIS SCREEN!!!! (It can save you lots of headaches as it did me) You can only get to it when you remove the VST tank cover, but once off, its a simple fix and free, an easily cleanable screen.

I cant say my problem would be the same as "everyone" elses with hesitation on these motors.....but I thought it worthy enough to mention, cause its so simple, yet such a PIA.

All that being said, the fuel burn on this boat is just getting to be too much, now that I have them running right and can in good conscience try to sell them with a good bill of health, Im gonna try to sell them and work on a repower down the road.

The motors are running great now, I cruised around at 45-4800 RPMs for miles today after the cleaning the filter, no hesitation, no surging, running great even my fuel economy improved.....not near enough though.

I call this my $2000 piece of debris.......
 

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