Yamaha 225 outboard stalling

I have a Yamaha 225 VMax outboard (V225TLRX). The engine started giving me problems two weeks ago. It ran fine out of the water but stalls under load. In the water It would idle fine, at WOT it would be fine for about 2 minutes then it would loose power down to 1000 rpms. The problem got worse and worse to the point that it wouldn't pass 2k rpms before loosing power and stalling.
I replaced the fuel filter on the motor and the inline water separator filter. I also inspected the VST filter and it was clean. I replaced the plugs and took her out again today. Now it will not make it to 1500 rpms without stalling. I checked the plugs and they all have spark although they seem weak. No water in fuel.
Now it won't start at all, even out of the water.

Re: Yamaha 225 outboard stalling

Check the fuel pressure at the end of the fuel rail and at the output of the Float Assembly( its where the HP Fuel Pump is) if there is no pressure than you Fuel pump is most likely bad.

Re: Yamaha 225 outboard stalling

Fixed it.:joyous:

It was the Flux Capacitor.
Not really, the Capacitor current was good at 1.21 gigawatts.

Actually it was the low pressure fuel pump diaphrams. Two out of three broken. Apparently the original diaphram is made of a plastic like material that gets britel and breaks. The replacement part is a rubber material. I originally sought to replace the entire pumps but the dealer did not have them in stock, so I did it the hard way by just replacing the 3 diaphrams and gaskets.
For those attempting, you must remove the high pressure pump out of the way. Be carefull each one of the 3 bolts holding the high pressur pump has two washers, the washer behind the bracket will fall, place a rag to catch them. The three low pressure pumps have a spring inside that have a metal cap on it, be carefull not to lose the cap.

I took her out today and she purrs like a tiger. Now if I can only hit 88 MPH.......