Water in the lower unit oil??

[smokeyjoe 2]

I have a 1983 150hp Merc on a 1986 Stratos that I just got two week ago!! I checked the thing out all over before I bought it and didn't find anything wrong with it including the lower unit oil!! But a friend of mine told me to keep watch on the lower unit oil because a lot of people will change it right before they sell!! Well, I've taken the boat out 3 times and thought I would check the oil and it has water in it!! How does it get in there and how do I fix it???

 

[andrewkafp]

Re: Water in the lower unit oil??

Drain it and re-fill. Buy NEW plastic washers for the fill and drain screws. Run it a few times and re-check. If still there, you need to get it pressure tested for warn seals. If it is found to be leaking, the seals need to be done. This is a job in most cases left for the experts who have the equipment for removal and replacement of the geargase internals and the means to conduct tests.

 

[Oldsaltydog]

Re: Water in the lower unit oil??

In addition to the washers at the screws, water gets into the LU usually in three other places: gear shift rod seals, the water pump gaskets and main shaft seals, and the prop shaft rod seals. If you are mechanically inclined, the job is possible to do, with the help of a good manual and a "lower unit seal kit" from Mercury. (Make sure to drop the LU in neutral and reinstall it in neutral.) But it is much easier (and more $$$) to have it done by a mechanic.