My mercury will run great for a short distance and then sputter out and the motor will shake and start to die out. It idles fine and is fine at low RPM’s. When it dies out, I can turn it off and start it up again and it will run great again for a short distance before dying out again. I disconnected the neutral safety switch which initially fixed the problem but it isn’t doing the trick anymore. Everything seems to be functioning normally, I need help.