I just had my carburetor upgraded to an electric choke from Rochester Marine (ebay was have price) is supposed to fix vapor lock but its not hot enough yet to test it
I have a 1990 220 DA similar to yours I have a hummingbird in hull works great except water temp which is best for fishing (I assume this is not strictly a fishing boat) I would think a thermometer would be easy enough to install without putting a h...