RPM surge

[J-cubed333]

I have a 1997 Yamaha 150HP Saltwater II. While running at about 3/4 throttle, I will experience a short rpm surge. Then the engine will return to it's normal rpms. It will only last a second or two. It may occur two or three times while on a ten mile run. Also I may get the same surge just as I begin to throttle down. I thought it might be a problem with a fuel filter or throttle linkage.

[boats.net]

Possible a fuel restriction, check hoses, filters and antisipon valve.