Yamaha 2006 50HP EFI...need help

My Yamaha 50HP EFI goes into limp mode after remaining at full throttle for a minute or less. Have changed fuel line and bulb. Looking for a place to start troubleshooting. What are the most obvious reasons this may occur? all help appreciated.

Wax

That lift pump has had some issues. I've seen them stick in the compressed mode. When you say limp mode are you speaking of overheat/low oil rpm reduction? Does it help to pump the primer bulb? Alarm sounding?

PBR,
Thanks for the input. I am not sure what compressed mode is or where the lift pump is but I have a manual that I will look it up. The symptoms talk to fuel starvation and oddly enough, as it starts to fail and go into "limp mode" (loss of power but motor runs in idle), you can pump the bulb to keep it going at higher RPM but it ends in a loss of ability of the bulb to generate suction from the tank. Have checked and the submerge tube filter in the tank is clean.
I Understand that overheating is a potential cause but water flow is good during failure. No alarm sounding......

If your primer is sucking itself flat then you have a restriction between it and the tank. Is the primer oriented vertically with the arrow pointing up? If all that is good then take the lift pump off the back of the motor and see if the plunger will stroke in/out fully. Some of those for some reason stick in the compressed mode and won't pump unless the spring can push the plunger back out.