2002 Yamaha F115 runs fine for a while and then starts to backdown

[Jeffsam1017]

2002 Yamaha F115 runs fine for a while and then starts to back down. I can shut it off and it will run fine again for a little while and then starts to bog down again. It has progressively gotten worse. After doing a little research I suspect a clogged VST any ideas before I start taking it apart?

Thanks!

 

[99yam40]

air leak into the suction line or a restriction could cause this.
tank vent clogged is the 1st thing to check.

then monitoringfuel pressures and vacuum to help identify the problem