2001 sugar sand tango 210 hp Mercury carbureted surging

I have had my boat with 210 hp Mercury carbureted engine into the mechanic multiple times. They miss diagnosed the problem and messed with the carburetor. Did not replace the fuel filter cut my hoses and reassembled with jets in the wrong spot. I rebuilt them myself replace the hoses and fuel filter. It ran great last fall. Even took it to Florida and into the gulf. Rinsed thoroughly and winterized it per manufacturers instructions drained all the gas just to make sure there would be no chance of sediment. This spring it started up kind of rough and smoked a lot as it usually does. Once running it seem to be OK other than a surging in the engine. It seems to be doing it worse when under more power or load. Somehow less in the corners. Here is a link for a YouTube video so you can hear it and maybe help diagnose it. https://www.youtube.com/watch?v=SQ4LOhQlVZc&feature=share
I am not with the boat but going this weekend to try to remedy the problem. Some suggestions I got were pinching fuel line or bad anti-siphon valve.
My boys and I really need to get this thing running good this summer. Thank You

I've got the same problem. What was wrong?