Lower Unit Oil Opinion Wanted?

[peter]

Peter I have been using ST Matthews Marine the last couple of years. They are a spinoff of St Matthews Imports and are located off Westport Road right next to Ken Towery's near the Ford Plant. If you are having issues call and talk to Tim he will help you out. Did you save that lower unit oil?

Thanks. I tossed the old oil. I'll keep St. Mathews in mind if i need to take it somewhere.

Thanks again.

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[R19]

I would do a pressure test on the lower unit to verify there is no leaks. You will have to drain the lower unit. A pressure test pump has a fitting that will screw into the lower unit drain hole. Then you will pump air pressure into the lower unit ( I think 90PSI ) If you have a leaking seal you will loose pressure. If you can matain air pressure for a couple of minutes then your seals are good.


If you do not have access to a pressure test pump you may be able to determine if you have a leak without a pressure test. The most common reason a lower unit absorbs water is from fishing line getting caught in the prop. The line will wad up behind the prop shaft and get caught behind the seals and that is where the water will come in. I would pull the prop and prop nut and look for fishing line. If you find fishing line then you will need seals.

[R19]

Forgot to add...make sure you install new O rings in the upper and lower drain plug. You can get a dozen O rings a an auto supply store for a couple of bucks. The O ring when compressed tight will allow the screw to form a leak proof seal when the screw is tight. If you continuously using the same O ring the water tight connection/seal can become weak.