1988 Yamaha 200 power loss at high RPM

[makojoe238]

I have a 1988 200 hp that looses power above 4000 rpm. It will continue to run full strength if the primer bulb is pumped. The fuel lines and filters are new and my buddy seems to think it's the high speed fuel pump because it runs fine from idle through 4000 rpm it starts to bog down around 4500 rpm but will run fine if the fuel bulb is pumped. I believe there are two fuel pumps on my motor. Which one is the high speed pump the upper or lower one. They look identical and carry the same parts number. Should I replace the both of them?

[makojoe238]

Any input would be appreciated.

[Tucker]

Sounds like you need a service manual. Both pumps are low preasure and one or both are bad. I'd replace both, they're cheap. Note sure about a 1988 but I think your HP pump is inside your VST. Sounds like that's never been serviced.