I just got an older 31 ft center cosole with twin Johnson 200's that are carburated. I have the toughest time starting them without fludding them. Should I hold the choke in the whole time while trying to start them? Should I pump the throttle while trying to start them? What is the correct process for these engines assuming they are in perfect running condition. This is my first boat that is not fuel injected and I am stuck with these until I can afford new engines. They are reliable once started but questionable if they sit more than a couple of days.