1997 200hp Mercury EFI won't start

[Les Welch]

I have a 1997 Lund Pro-V with a '97 Mercury 200hp EFI motor. It hasn't been run in 3 years. I did pump out all the gas I could get out three years ago. This week I added a can of seafoam, 15 gallons of pure premium gasoline, and put in all new batteries. Last night I pumped the ball, actually too much as gas started to run out the motor. I turned the key and it fired immediately and ran really rough for 2-3 seconds, it was blowing out some of the fogging, and then I killed it. It wasn't in the water or have muffs hooked up. As long as it fired I thought I would take it down and back it in to the lake and just let it idle for awhile. Well of course once I got there it wouldn't even fire. I took it back home. After sitting 10 minutes it fired again and sputtered for 1-2 seconds and died. It did this 20-30 times through out the course of the evening. Now I can't even get it to fire, it just cranks and cranks. I've read what feels like about 200 posts this morning. I'll be able to look at it again tonight, I'm working today.

Things I plan to do tonight, and tell me if I am wrong or shouldn't do these.

1) Check both battery terminals and make sure they are good and clean, and the nuts are tight.

2) Check ignition switch and make sure nothing is loose.

3) Pick up 6 new NGK plugs and install.

I'm not mechanically inclined. I don't mind taking stuff apart and trying to fix it, I just don't have much experience or knowledge doing it. Just blindly taking it to the mechanics here when I don't know what is wrong with it scares me. They charge $100 an hour, that adds up damn fast.

What are all of your thoughts?

Thanks,

Les

715-579-3345