So yesterday I took the fuel tank off my Boston Whaler and connected in directly to the fuel line north of the primer ball. No change, same issue. I replaced the filter fuel filter that resides in the small bowl with red floating gasket in the very front of the engine No change, same issue. I replaced all 4 spark plugs, upon removing the old plugs all four looked just about the same No change, same issue. I traced all fuel lines in the engine and I don’t see any visible issues. I called a mechanic and he is coming tomorrow. Told him I would pay double his hourly rate to get bumped to the top of the list. I posted a photo of the auxiliary tank I connected and the throttle the throttles when port is a 4200 RPM and Starboard as at 3800 RPM. BTW- I also inspected the throttle position on one miter and compared to the other.