5.7 mercuriser, Probs after sitting for a year

[phsncatalina]

Hi guys, just fired up the boat yesterday after sitting for about a year & 1/2. Took me some time to finally get it running and once it fired up it seems to be sluggish. There is a second or two bog/hesitation when it's givin a quick rev. almost stumbling before it picks up. However, if the throttle is slowly moved forward, the reves will climb without problems. Additionally, it's much harder to start now...it will turn over 10 or so times before comming to life, even when I re-start it right after shutting it down. What basic things do you guys recommend I do to kinda tune it up after the long wait. Its just kinda running crappy, not the snappy engine I remember. I have a 1997 5.7 Mercuriser all stock except for performer intake and holley 600cfm marine carb.

[gonzo]

Probably the carb needs a rebuild. The power valve in those Holley can get clogged or damaged with a backfire too.

[DangerDan]

Tuning it up is a good start. Was the fuel in the tank from the layover? If so maybe adding some dry gas would help. I'd do the tune-up and run a good dose of Sea Foam through it if that doesn't clean it up then I'd agree with the carb re-build.