Outdrive Leaking Oil

[s73vo]

I have a Volvo SX-M drive on my boat and I have been having an odd issue. I keep the boat on a trailer and whenever I go to put it in the water I notice that the drive is leaking oil. The oil is NOT coming from the prop seal it is coming from up under the cover by the shift linkage. The shift linkage seal looks fine. It has been leaking for months. When I see a puddle of oil under the drive and it running down the side of the drive I noticed that it was not milky at all. I even drained some oil from the drive as well to check for water. I keep checking the level of the oil and its always above the minimum. How can it be leaking oil, not drop below the minimum, not take on any water, and still leak? Is there possibly a vent on the drive that could be clogged? Could the sun be heating up an air bubble inside the drive that expands and forces the oil out a seal? Could the gear lube be old and breaking down and expanding? I am taking the drive off soon to change bellows and gimble. If there is a seal that needs to be changed now would be a good time to do it.

 

[Scott Danforth]

remember, if oil is going out, water is coming in.

time to pull the drive, drain it, and pressure test it to find out what is leaking

 

[QBhoy]

you certain it isn't coming from trim system ?

 

[s73vo]

you certain it isn't coming from trim system ?

Yes. It is gear lube that is leaking out of the seal for shifting. The seal itself is above the vent plug for filling the drive. Meaning that there shouldn't even be gear lube up there when its sitting on the trailer. I attached a photo for more context. I will replace the seal. But still doest explain the high lube levels. The boat has been sitting on the trailer for 3 months unused. I went there today and took this picture. It was leaking again today. It has not been in the water. kind of negates the possibility of water getting into the drive and causing it to leak.

 

[Lou C]

The leak is what causes the high lube levels, the drive as it cools off will tend to suck in water and that pushes the oil level higher. There just may not be enough water in the drive yet to turn the oil milky.

 

[BRICH1260]

I would at least plan to replace to that shift seal, not too difficult to do. While you there, I would drain the old oil and fill with new. You might plan to check the drive oil periodically to make sure no water is still getting in.

 

[QBhoy]

Yes. It is gear lube that is leaking out of the seal for shifting. The seal itself is above the vent plug for filling the drive. Meaning that there shouldn't even be gear lube up there when its sitting on the trailer. I attached a photo for more context. I will replace the seal. But still doest explain the high lube levels. The boat has been sitting on the trailer for 3 months unused. I went there today and took this picture. It was leaking again today. It has not been in the water. kind of negates the possibility of water getting into the drive and causing it to leak.

Got you. There will be oil up there when it’s running. It’s kind of splash lubricated when in operation. So oil thrown everywhere really. Know what you mean though.

 

[DRCrowe]

I just replace the shift seal on mine as it was leaking pretty bad too. There is a helpful youtube video that explains the 3 different types of possible shift plates. (search AYR Cave Shop - part 5 shifting cover).
I saw the 3 options offered by Volvo in the manual, but the video did a good job of filling in a few gaps and showing how it works and should be adjusted.
As always, if you are going to put in the effort, use genuine Volvo Penta parts.