Yam 150 4 stroke RPM problem

[jtk7873]

04 Yamaha 150 four stroke. I'm having trouble with the rpm's getting up past 3000. I had the tank flushed and the filters replaced, but I still can't get the rpm's over 3000. If I pump the throttle while I'm running, the boat picks up speed, but as soon as I stop the rpm's drop back to 3000. I'm racking my brain trying to figure out whats going on with thing. any ideas?

 

[rodbolt]

Re: Yam 150 4 stroke RPM problem

small rack?
what does the primer bulb do?
a hint, it bypasses the fuel pumps.
check fuel system vacume,test fuel pump out put and repair as nessasary.
the fuel pump diaphrams are replaceable cause they simply dont last forever.
test fuel rail pressure at the problem RPM, if it can hold about 35 PSI then send the injectors out for cleaning.