Broke down in the middle of the lake today. Had to play Hurt by Johnny Cash and hang a white towel for surrender...merc 260 in an 82 cobalt. Engine shut off at idle. An hour or so prior when I tried to start it just clicked so I thought, ok starter. Tapped it with a hammer while my buddy cranked and it started. When it just shut off I tried to do the same thing but it was acting like the battery was dead. It would barely turn over. Luckily, since it was the first time out this season I thought, I should bring my jump box. So I hooked it up. No change. Only for worse. Tapping on the starter and jump box hooked up it just stopped trying to turn the engine over at all. Still clicked though. Jump box said it was fully charged and this thing will jump start a dead diesel. It really sounds like the starter is trying but it just wont turn the engine over. Oil is clean and full. Would the engine lock up like that or is it the starter? Just dont know what else it could be. Any help would be much appreciated. Im thinking I may take the battery, alternator(easy to get to) and starter up to Oreillys and have them tested. The starter is just in such a crummy spot.