Problems getting on plane

[Divine Comedy II]

2004 280 Sundancer at low rpms the boat runs fine, usually get on plane at 3000 to 3100 rpm. Noticed that throttles are no responsive enough when pivoting and docking and throttling up. The cables have been adjusted numerous times, and getting worse. The boat just before getting on plane experiences cavitation at an rpm well below the normal rpms needed to get on plane. It now takes a much higher rpm to get the boat on plane. All of this has been tried in varying wind conditions with the same result. We cleaned the props and buildup on the back of the boat so we do not think that a dirty bottom is the problem.
Wondering if we have 2 fold problem. Bad trottle cable or bad engine. 7 days prior we put in 50 gallons of gas at a new gas dock that has a lot of turnover, and then the boat sat for a week. Prior to gasing up the boat ran fine with the exception of the non-responsive throttle.
Any ideas?

 

[Sundancer]

When you say non-responsive, is that due to slack in the cables or are you talking about the engine rpm when you move the throttle? What is your WOT rpm and does it indicate you have the correct props? When was the last tune-up? When did you replace the fuel filters last? All MIGHT be contributing factors!

 

[Divine Comedy II]

Thanks will take under adisement. Have the correct props, tune up 2 years ago at 100 hrs, now at 130 hrs. Cables have been adjusted but will check the filters.

 

[richcam1]

Just a thought, check if your engines are trimmed all the way down? I have a 280, sometimes if my engines are up a tad mine reacts the same way.