Any Boat mechanics around

I got a 16 foot, some indian named boat, with a 1973 Johnson 50 on the back. Heres the deal. The guy let the a$$ end sink at his dock. The motor was under water maybe a half a day. He pulled the plugs and tried to get it to crank but it was locked up. He gave it to me for $150.00 for boat motor and trailer. Cant beat that. I got to the house, pulled the plugs, sprayed the cylinders with PB blaster and worked the flywheel back and forth and it turned over within a few. The starter silinoid is bad and I think the carbs are stopped up. It'll crank on starting fluid, but thats as far as I've gotten. Anyone want to help a brother out. Its my first boat and I'd love to get at least one good run before I take it to the lake and sink it.