350 Mercruiser will crank but won't fire up

[Iowaboatguy]

I have a 1991 5.7 L Alpha One I/O (350) on my boat. When I go to turn the key it just keeps cranking out won't fire up. The battery is charged, carbs cleaned, spark plugs changed, throttle has been primed. We were having this problem before and we could manually open the carburetor on the motor while turning the key and that would do it. But now that does not work. I have used starting fluid to no good either.
Any idea what could be wrong?

 

[greno]

You don't need to start a new thread. Just continue posting in the thread you already started.

 

[achris]

One problem, one thread.

Topic closed.