"Glenn Deneweth" wrote in message
...
I have a 230hp 305, with a Mercruiser Alpha 1 (1986) and this year when I
run the engine there are a strong smell of gas fumes, the engine is
running
rich. It also runs a little rough. Would turning the mixture screw fix
both of these issues?

The screws only adjust the idle mixture. If you get the symptoms at
anything above idle then this won't help.

How do you know the engine is running rich?

A strong smell of gas is bad, so you should solve that problem ASAP.

Rod