Here's another in the series of my "stupid newbe questions". This weekend I was finally taught how to change out my lower unit oil on my 50hp OB by Damon. I also bought a shop manual for my motor and read in the maintainence section that I was suppose to be changing my lower unit oil every 25hours. Yikes! Well needless to say when we opened the drain, the oil was pitch black and oozing out of like melting plastic. I've put at least 200 hours on it since I bought it this year and have never done it. Who knows how long before the owner before me did it also. We also found metal shavings on the magnetic drain plug. <br /><br />Now that I've learned how to do it, I'll take care of it more religously. <br /><br />How often do others here usually do this? Is doing it every 25 hours too excessive? Because I've heard of others doing it every 100 hours, and then some that say they do it bi annually.
