Here's a "Talk About Anything" - II

[Doc]

I would think he could go 150 or 200 hours with syn.
However. Oil degrades after 12 months of use.
If he puts less than 100 hours on it each year AND he plans to change oil annually it really does not matter which oil he puts in. Might has well go with cheaper dino. Rotella is great for diesels.

 

[geohorn]

I would think he could go 150 or 200 hours with syn.
However. Oil degrades after 12 months of use.
If he puts less than 100 hours on it each year AND he plans to change oil annually it really does not matter which oil he puts in. Might has well go with cheaper dino. Rotella is great for diesels.

I’m curious about when folks say oil degrades with time. I had a pallet-load of Mobil “Red-Band” SAE 50 aircraft oil given to me by a distributor who was retiring. (It was a lot easier for him to give it to me than it was to try to dispose of 50 gals of unused motor oil.)
That oil was last produced in the late 1950’s…so I’m guessing it could be maybe 70 years old. A different oil distributor told me not to use it for anything other than door-hinges because it is “deteriorated due to age”. Mobil Oil Co. (now Exxon-Mobil) refused to comment on it.

I used it over a 15 year period in my Ford 9N tractor, lawn mowers, etc etc without any trouble at all. I figured that if it sat underground for 20-billion years before it was refined…it MUST be ”OK” AFTER for at least another 100 after it was refined and put into metal quart cans.

Shell Oil Co. states that aircraft engine oil (a product not nearly as sophisticated as automobile engine oils) has a shelf-life of 2-years. I’ve got several cases of that sort of stuff varying between 3-4 years old which I bought in quantity and use regularly in two personal airplanes without any qualms whatsoever.

Any reliable proof that refined motor oil degrades during ordinary storage?

 

[bczoom]

I'm with you @geohorn
AFAIK, it doesn't degrade until it goes in an engine and meets all the impurities and temps in the engine itself.

 

[Doc]

I'm with you @geohorn
AFAIK, it doesn't degrade until it goes in an engine and meets all the impurities and temps in the engine itself.

Exactly. that's what I said. It degrades after 12 months OF USE.
And I think 12 months is a rule of thumb. I read this on Bob's the Oil guy page. And abide by it.

 

[bczoom]

Exactly. that's what I said. It degrades after 12 months OF USE.
And I think 12 months is a rule of thumb. I read this on Bob's the Oil guy page. And abide by it.

Was thinking about this yesterday when mowing the lawn.
Yea, it would be nice to change the oil every year but for me, it isn't practical.
I took an inventory of my 4-stroke and diesel engines (2-stroke don't count for this subject). I counted 26 engines. 25 of them are in running condition, one is down for an electrical issue. Changing them all annually would be a bit much. Some of the engines are rarely used.