motor losing rpms while on plane

[brems]

2003 175 ficht
I take off, boat planes off, going along fine and then I lose RMPs and this continues until I back off. No alarms and the motor stays running. I take off again and it runs fine. Out of 15 take offs this has happened 3 times and when it happens it is with in 10-20 seconds after planing out. Any ideas??? To me it seems the motor isn't getting fuel.

Replaced the primerbulb and, so far, same issue.

Any help is certainly appreciated.

Serial Number 05006169 Model # e175fplstb

[RUSTY63]

Get an inline vacuum guage with a one foot section of clear hose, run the motor at idle and check the guage reading, you should not see more than 1.5-2.0 on the guage and there should be no air bubbles in the clear hose.

More than 1.5-2.0 indicates a fuel restriction and air bubbles indicate an air leak.