3.0 Mercruiser?

Hello. Could anyone help me out before I buy a boat with the 3.0 Mercruiser. The boat itself is a 99 maxum. Its a one owner and it has sat for the last 6 years he took it out this year and it ran rough but all that was done was new oil and topped up the old gas. I really know little about boats but want to learn. The overall price is really really good. It does need a good cleaning as it has been neglected for those years. Is this a engine that is good and could use very little to tune it back up or could I end up needing to put thousands into it? Thanks for any input.

I would suggest getting a Can of Fresh Gas, run from that and check it..
Sitting 6 years, it would at least need a proper Carburetor Cleaning, and replacing the Water Impeller..

plus a few other items ..

the 3.0L is a Good Engine.. expect 30-35mph

Boat looks clean

Pump out old fuel first, and have tank cleaned.fuel lines replaced,filters changed,carb removed,thoroughly cleaned,plugs cleaned ,or replaced All cooling hoses inspected. Drive gear oil dropped,and inspected for metal. Inspect ignition system,wires,cap,rotor,ETC. clean battery connections +and -

Thanks. Im going to meet him at the lake in about 4 hours. He will let me test it on the water. Should I take anything with me? Like I say this is our 1st boat. The price is about half of what others are going for its a older gentleman that just wanted it gone before the weekend and I happened to be the 1st who called. The price is great but always worries me a little. He has told me everything that does not work and they seem to be simple fixes plus the tuneup Im expecting.

Save yourself some annoyance, just change the cap, rotor, plugs and wire, While you are at it, inspect the belt(s) for crack and rot, replace if any doubt. If possible, get a compression check done before forking over real money.