DT 225 power loss

[Jetfixr]

Hello all, I have a 2003 DT225 on a seapro 206cc. The engine has less than 100hrs it sat for years, Above 3000 rpm it just won’t clear itself and run up to 5200, I’ve looked at filters high and low, ive inspected vst can, pulled plugs etc comps are great I’m stumped I added a racor changed lines changed fuel vent, added new blue bulb I use the lines that are without the vinyl liner, other lines just really are terrible, I’m stumped please if u could give me some advice, all the shops around look at me like a Martian when I mention DT225, as if it’s a really an odd duck but I would like to try to get it sorted, can’t quite get a new 4 stroke yet, besides, low time, I just can’t justify the money yet. Guys I’m looking for self help advice. I can fix a damn 747 and a 6 banger outboard is kicking my behind. Looking for kind advice.
thanks in advance
Jet.

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