Re: changing lower gear case oil
just as an aside...I once look at the spec. sheet for Lubrimatic marine lower unit oil and a standard Lubrimatic 90 wt. oil. The spec. were identical! Secondly when filling lower unit always fill from the bottom hole and let the oil be forced out the top. TO DO THE REVERSE IS A DISASTER. Put the top plug in first. You lose very little oil when you then put in the bottom plug. If the oil is milky, you have water in it. Besure to change before winter or it will crack the gear case housing. A last point...if you do crack the lower unit, try repairing with epoxy, works great if cleaned properly. A lot easier and cheaper that welding. Just a thought.