Gear oil alternative in the middle of nowhere?

[epiic]

I am low on gear oil in my Mercury 9.9hp outboard in the middle of the Bahamas with no store anywhere nearby that sells gear lube.

I came up with 3 scenarios...

1) Drain all the gear oil and replace with Royal Purple 10w30.

2) Top off with Royal Purple 10w30 and mix the two together.

3) Leave it alone and run it with low oil.

[mike d.]

Add to mix! If you drain and use crankcase oil it will not provide enough lube coating! Change out as soon as possible to regular gear oil!

[LeaseOnLife]

Originally Posted by epiic

I am low on gear oil in my Mercury 9.9hp outboard in the middle of the Bahamas with no store anywhere nearby that sells gear lube.

I came up with 3 scenarios...

1) Drain all the gear oil and replace with Royal Purple 10w30.

2) Top off with Royal Purple 10w30 and mix the two together.

3) Leave it alone and run it with low oil.

any heavier weight oil available? 40W straight?.. or even 80W, 90W?

low oil is worse than wrong oil, but low viscosity oil will destroy gears earlier, I would mix if absolutely needed, but keep the engine on low power until I have proper oil.

[epiic]

Originally Posted by LeaseOnLife

any heavier weight oil available? 40W straight?.. or even 80W, 90W?

low oil is worse than wrong oil, but low viscosity oil will destroy gears earlier, I would mix if absolutely needed, but keep the engine on low power until I have proper oil.

I've got Rotella 15W40 Triple Protection that I use in my Yanmar Diesel.

Would that be better?

[belizesailor]

Gear oil is normally single viscosity. I think get the highest single viscosity oil you can find and top it up. Alternatively, use whatever youve got. Eitherway use it gently until you can do a full change.

[UNCIVILIZED]

Have you looked to places that sell oil/lubricants for other uses besides outboards? Such as automotive, industrial, or even lawn care. And you might even approach anyplace that has a commercially used vehicle in their garage, or more than one, to see if you might buy/barter with them for a few quarts of something useful. As they may have a bit extra tucked away for those times when the supply ship is late. Ditto on any mid-sized/larger commercial vessel. Or possibly even try an airfield.
Someone's likely to have something that'll work, it's just a question of finding them, & making the right offer

Also, look up the spec's & operating range of the factory approved lube, & then compare them to a dozen or so alternative options in order to see what else may be "close enough" for now. Like say, the oil used in a car's differential (rwd type vehicle).


PS: 8' oars may do the trick, if you pump up the dink super hard, & sit on the floor on top of a cockpit cushion to row instead of the normal dinghy seat.

[01kiwijohn]

Try these guys, I'll bet they have it.
Machinery & Energy, they're a Caterpillar Machinery dealer. on College Ave, Nassau,
If they don't have it, there's a Mack Truck dealer just down the road from there.

[Paul L]

How do you know it is low? On most small OBs you fill from a lower plug and stop when it flows out the upper.
The locals in the Bahamas use lots of OBs. They should have some gear oil stash.

[DeepFrz]

Originally Posted by belizesailor

Gear oil is normally single viscosity. I think get the highest single viscosity oil you can find and top it up. Alternatively, use whatever youve got. Eitherway use it gently until you can do a full change.

Multi viscosity oil will work as well as single viscosity if that is all you have. What you are interested in is the highest number. Your 15W40 should be okay so long as you run it easy and for the shortest time possible until you can replace it with gear oil.

[Cadence]

How low? If a little leave it be. The full plug is generally well above the gears. I would be concerned why it is low and is it milky. Have you picked up any monofilament lately? That will do a job on the prop shaft seam. If you can find any 80 or 90W hypoid us that.

[mrm]

OK, so Mercury is not a Volvo, and an outboard is not a saildrive... but our Volvo mechanic replaced the factory oil in the SD with the same oil (15W40 IIRC) he used for the engine. When questioned he actually presented a factory service bulletin advising to do just that.. Just a n=1 sample of what is being done.

[a64pilot]

Wrong oil is better than no oil, mix it though, not straight crankcase oil, either you have will work.
Flush and fill when you can.

Hypoid gear oil is different, its not just the smell.

[MCOS]

Add STP or similar engine oil "fortifier" as emergency band aid approach. Can't believe if you can find gas and oil that you can't find gear lube.

[belizesailor]

Originally Posted by a64pilot

Wrong oil is better than no oil, mix it though, not straight crankcase oil, either you have will work.
Flush and fill when you can.

Hypoid gear oil is different, its not just the smell.

That is Volvo's, often changing, recommenation. Very handy to only need one oil.

But, Ive never seen that recommendation for any OB.

I agree though that technically wrong is better than none.

[Cadence]

Originally Posted by a64pilot

Wrong oil is better than no oil, mix it though, not straight crankcase oil, either you have will work.
Flush and fill when you can.

Hypoid gear oil is different, its not just the smell.

It is different I'm sure but has been used for rear end banjos for years which are more complex than a lower unit is. Not a long term recommendation. Possibly to viscus for low HP? Something like Rotella T might work great.