Merccruser 5.0L carb Run with not power then fine

[scott449]

Merccruser 5.0L carb Run with not power then fine
Boat starts fine. Hit the gas and it goes but has a really hard time will get to about 2800 RPM and take about a minute to plane. Once on plane will go to about 3400 RPM for about 1 min then the power will start to kick in and I can get it to about 4500RPM and runs like I should.

Any idea why?

Things I know are good
New fuel
Clean and dry distributor cap
Clean dry roter

 

[alldodge]

When was the last time the fuel filter was changed?
May need to pull the top of the carb off and see if there is any crud in there, and if so it needs a rebuild
Check fuel pump pressure at the carb, also fuel flow.