Yamaha F150's

[Tiresfirst]

Twin F150, still under warranty. Third time port engine started idling bad and will only achieve 4000 rpm. Racor 10 micorn for each engine. One gas tank feeds both engines. First time was told clogged injector. Second time said injectors clogged and had to pay 300.00. Same thing again after 10 hours of running. filter in front of engine clean, racors changed 20 10 hours ago. Thoughts please. Only port motor doing this. Don't see how it could be fuel if only one engine doing it?

[Sequoiha]

if cleaning the injectors is taking care of the problem, only if for 10 hours then its fuel, are they replacing the basket filters in the injectors. it could be the fuel pump in the vst, i have seen them start wearing and producing metal powder, the evidence will be in the basket filter.

[rodbolt17]

welcome to the US govt marine technician stimulous program.
also known as the ethanol mandate.

[Tiresfirst]

F150

thanks, have 200 hours on thye motors. No doubt it is something in the fuel, but I feel it has to come after the racor and the front onboard filter. Weather something from the pumps or the coating on the vst tank. The other motor runs like great. Please keep info coming and other experiences. I do appreciate the input.

[rodbolt17]

have they removed and cleaned the VST tank?
have the engine fuel lines been checked for contamination?
while the intake is off they can look for plastic contamination.
some poly tanks and poly draw tubes dissolve with this fine fuel but the solution wont pass the VST/injector filters.
will leave a brown sticky residue on the intake runners and stick piston rings and trash pistons.

[Tiresfirst]

thanks for this info. I will follow up with them and keep all updated.

[Schematic]

Twin F150, still under warranty. Third time port engine started idling bad and will only achieve 4000 rpm. Racor 10 micorn for each engine. One gas tank feeds both engines. First time was told clogged injector. Second time said injectors clogged and had to pay 300.00. Same thing again after 10 hours of running.

Ditto Sequoiha
I've seen this before. Had a look into the basket filter in the injector with a microscope. Found brass granules. Going to install a 10 Micron filter between VST and fuel rail.

If they are charging you, get them to show you what is plugging the injectors. If its metalic, they should be changing out the high pressure pump under warranty.