Can anyone tell me when they would have a new motor serviced? It's a 60HP 4-stroke Merc with about 15 hours on it. (alwaysn freshwater) I'm a total motor moron, so I won't be doing anything myself (I have checked the oil several times). I want to protect my investment, so I'd rather go in a little early, than a little late...<br /><br />Any suggestions?<br /><br />THANKS in advance!