Have had ongoing issues with my 2015 Mercruiser 4.3L TKS (carbureted) / Alpha 1 I/O. After running it for 30 minutes at 2000 a 3000 RPM on the lake, I head back to the dock, throttle back, and it dies. Can only restart it at 1/2 throttle+ but as soon as I cut the throttle to get it in gear, it...