Gear lube in engine oil

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I have a 75hp Mercury 4 stoke. I changed the oil and filter and added 5 litres of new oil. I needed a little more to top it off but unfortunately I grabbed my gear lube. I quickly caught myself but probably added 50ml of gear oil to the engine oil. Question, am I ok to run the engine with this little bit of gear oil or do I need to drain and add new oil? Thanks
 
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That is under 2 ounces , that isn't much.

My only experience with this was years ago at a car dealer, the bulk oil tank for 30 w got filled with 90 gear.

Several vehicles came back with damaged engines .
 
5 Liters = 5,000 mL oil and 50 mL gear oil.

So you added slightly less than 1% gear oil (please check my math).

I would not worry about it in my boat and I have Mercs.

10w30 or 25w40 ?
 
Follow-up.

Now you have me wondering what the effect will actually be.
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Is it the Mercury High Performance Gear Lube SAE-90 or the Premium 80W90 ? I am assuming you use premium for outboards?

For some reason these two are not be mixed:
https://www.mercurymarine.com/en/us/part...ants/gear-lube/

I don't think 1% is enough to matter but lets see what a tribologist says.

Edit:

I am running by West Marine shortly and I will ask them why the two lubes can't be mixed. That might provide some insight as to they will countersct with motor oil.
 
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Gear lube has sulfur in it which will attack your engine internals. How much, IDK, but it's not good.
 
Originally Posted By: MolaKule
I would change it before winter storage.


Good to know but the OP lives in FL, his winter may not be the winter you think.
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I don't think it'll hurt anything. I have known many people who have added an entire quart to their car engines in the past.

Maybe run the OCI a little shorter than usual.
 
Originally Posted By: ArcticDriver

Good to know but the OP lives in FL, his winter may not be the winter you think.
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Ontario is in Canada.
 
Originally Posted By: Linctex
Originally Posted By: ArcticDriver

Good to know but the OP lives in FL, his winter may not be the winter you think.
grin.gif



Ontario is in Canada.


What the heck, I could have sworn it said Orlando.

Guess its time to get a stronger eyeglass prescription.
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Gear lube and yellow metals may not be compatible (depends on the lube)... 25W-40 is stout oil and the add pak will likely absorb the gear oil OK. I would not be concerned as this is tiny dose.

But I'd try real hard not to do it again
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