Here are a couple of pics of the oil that came out of the lower unit of my 75 HP Merc ELPTO yesterday. This is the first time I've waited until spring to change the oil. I usually do it following the final trip of the year. There seemed to be a distinct seperation between the two colors or oil, but there wasn't any seperation of water. I would think if it was water getting into the foot, it would have seperated back out over the winter. While I had this drained I also replaced the impellar and water pump seals for the first time since I've owned the boat. All seals and impellar looked good.
My question is; Do I have a bad seal somewhere in the lower unit? Is the discolored oil from water infiltration or something else?
[signature]
I'm not a motor mechanic, but last time my oil look just like that I had a bad seal in the lower unit. However, when I had my impeller changed the seal in the lower unit was also changed at the same time. The reason for no separation of oil/water is that the water has been so thoroughly mixed into the oil (emulsificed) that it will no longer separate over time and just comes out milkly colored. The milkly colored stuff can still freeze (and expand) and you run the risk of cracking your lower unit, not to mention improper lubrication due to the water in the oil. I would get it changed for sure. If you want a "professional" opinion, then email these pictures to Lee over at Lee's Marine in Hyrum and I'm sure he would be more than happy to let you know too. His email is: [url "mailto:leesmarine@yahoo.com"]leesmarine@yahoo.com[/url]
[signature]
google is my friend! you have a bad seal... well according to everything i looked up
[signature]
Agree. We have had a few boats that have had the same problem. It does not look bad, as our oil had turned totally white....total fail. It should not be too hard of a fix tho.
[signature]
You should be fine. Just change the oil at the end of the summer from now on. Our boats in AK always looked about like that when we changed the oil. Of course we ran the motor for 90+ days in a 4 month period. (We also changed the lower unit oil every 150 hours of running which worked out to be about every 6 weeks depending on areas we were targeting.)
What bear lake fisher said is true though, the water in there can freeze and cause problems, that is why we changed the oil out at the end of the summer, regardless of if it had only been in there 2 weeks or 2 months.
If all of your oil turned milky then you would need to get your seals replaced. Keep in mind the leakage may have come from a screw that had worked loose, or that was put in at an angle. There are many points at which water can enter your lower unit, the screws, the exhaust vent has a minor seal that can bust, or the entire lower units seals can go bad. If you ran the motor the whole season, and that is all the discoloring you got, I would say that one of the more minor points of entry, the screws or vent, is where your seepage came in.
PM me if you have any other questions, I am no mechanic but I ran a lot of boats over a 5 year period in AK.
[signature]