Slightest milkiness in lower unit oil. Should I be concerned?!?!

[Zwc1192]

As the title says, regular maintenance and I notice a little “milk” in the lower unit oil. Not much at all, but enough that it made me worry

is this an “acceptable” amount that could have gotten past the old seals on the drain screws, or should I look into replacing the water pump and seals as well as the prop shaft seal?

https://imgur.com/a/P2lDRc0


link to picture. Caught heck trying to upload picture directly to post

[bhjr.]

I would say yes, but other more educated responses will be along I'm certain.

[Zwc1192]

Yes it’s a tolerable amount or yes I should start replacing seals?

im thinking for as cheap as a quarter of fluid is, i may just run it a few times, change it again, and see if water has gotten in after just a couple trips.

[Bob G.]

I wouldn’t replace seals without first pressure testing the lower unit.

[DewRonInc]

Not bad, seen way worse

[bhjr.]

On our equipment, mostly Cat, we pull samples from the compartments that are being serviced to be tested for contamination. Usually, the samples come back clean, but I've seen reports come back indicating contamination that Cat tells us needs attention. All of this is in PPM. Usually can't see PPM. So, if you can see it, you should address it is all I'm saying. That compartment and it's components are designed to be lubed with oil, not oil and water.

[JOE54]

reseal gearcase may worsen very quickly and destroy gearcase should be no water in it

[SilverFox579]

Honestly, that's a small amount and could be from a drain or fill plug plug gasket. I'd drain fully, replace drain and fill plug gaskets, refill and go fishing. The nice thing about High Perf 90 is it emulsifies with water.

If you have the ability to do a pressure test, that would be a quick, peace of mind procedure.

[Zwc1192]

Thanks for the input guys.

I'm going to go fish it a few times and change it again for peace of mind. If it's showing water after only a couple trips out, I'll reseal everything.

[EuropeanAM]

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Replace drain and vent seals, add fresh lube to appropriate level and monitor/check after each of the next couple outings. Very unlikely that you're going to find anything with a pressure test (though there is no harm in doing one).