went (tried) to go fishing this morning, temp was around 35 degrees, had to choke it and put it at a fast idle to start it, when I backed out of slip I heard a clanking sound from possibly the lower unit area, and the engine kept dying, when I got it out in the river I slowly increased the power, it seemed to have unusual vibration, then ther was a loud snap from the engine, I was able to idle back to the dock, I didn't dare apply any more power to it. when I got home I put the muffs on it, started it, put it in gear, and there is somthing clanking around in there, I spose I'll have to take off lower unit and take a look around, can anyone tell me how to remove it?<br /><br />It is a 1997 150 offshore merc.<br />HELP