I just went to replace the gear oil in my 1970 55hp Seaking ob. What came out was a blueish, greenish color. I went to put in 90 wt hypoid oil but it was yellowish. Is the 90wt hypoid ok to use or should I use something else?
You should use any mechanical shift marine gearlube. Marine lubes have additives to keep any water that might get in there in supension much longer and that can save a gearset and bearings. What was in there was probably Mercury Hi-Perf gearlube. Many shops use that exclusively.
