It's also unusual for a failed fuel pump to give you trouble and then be OK, usually when they go, they are gone.
Check the fuel lines and see if one is maybe kinking or getting pinched off somewhere. Look for blockage in the vent for the fuel tank.
Dirty carbs are dirty inside, in the bowl and float areas and the jets and internal passages, spraying thru them does very little to help those issues.
If you are a handy mechanic you can clean the carbs yourself, Take them off, just like you did and open them up one at a time. Watch a couple youtube videos and have a pristeen clean well lighted work area. I uses spray carb cleaner for the small passages, make sure you can see through each passage after you think it is clean, use a strand or two of copper wire to pass through clogged jets. I blow them out with low pressure air from my compressor, regulated down to 4 or 5 psi. I use a dishpan with HOT water and Dawn to wash the big parts like dishes, then blow them out with the low pressure air. Check the specs and reset the float height, then put them back together the same way you took them apart. Any needle that looks at all deformed or hangs up at all should be replaced, deformed, damaged or fuel saturated gaskets should be replaced too. You should be able to get them clean without disassembling beyond taking the bowl off, pulling the pin and dropping the float off, taking the cap and gasket off the top if one is there and cleaning out all the passages you can get to from that point.
Visit boatinfo.no and find your manual, read the carb section a couple times and get familiar with you carb, watch a vid or two and maybe give it a go.
