A misfire causes gas smell in a hurry. Replace your plugs, plug wires,
distributor cap & rotor. These are fairly cheap and easy to replace. I
would then go to after the carb.

"Glenn Deneweth" wrote in message
...
I should mention there's no performance issues....Just a rough idle and
strong gas smell...


"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? I had the carb rebuilt 2 years ago, and tuned up
the
engine the same time. It's not running that rough, and but rougher than
last year. How long do spark plugs and wire last? I also have
electronic
ignition if that matters.

Thanks,

Glenn