Yamaha F225 bogging. Need some help...

[rodbolt17]

trust me, the HP pump cannot pull fuel from the hull.
what is rail pressure at the failure RPM and load?

that's the only why to test it.

if you can maintain 35-38 PSI at the failure RPM quit chasing rail supply ghosts.

you can also go old school on it and run it with the airbox removed and squirt fuel down each cyl,once rail pressure has been verified.
that can find injector issues.

would also be a perfect time to use YDS and record the data at the failure RPM and load.

a quick way to test the lift pump.

eyeballs baby.

simply watch the fuel cup level when idleing.

[thecowpen]

Rodbolt - thanks for your suggestions.

I've been meaning to get a YDS cable / software kit off e-bay for a while now. Will do that, hook up the pressure gauge and haul the boat to the ramp this week if I can get a day off.

I've never run the boat with the cowl off before, but I've also never seen the fuel cup anything but slap full. Will keep my eye on that too.

I appreciate all the comments and suggestions. Will update with results.