Engine oil date

[38mess]

I bought some oil for my engine a few weeks ago, 15-30 semi synthetic, and today I noticed a date on the nozzle of 12/12/21...03.35am.
I take it that's the manufacture date and not the expiry date?.

 

[Boathook]

I would expect manufacture date. I've never seen a time given for expiry before, even for food.

 

[wonkywinch]

It was in the ground for a few million years before it ended up in the bottle. I'm sure it will be fine.

 

[38mess]

It was in the ground for a few million years before it ended up in the bottle. I'm sure it will be fine.

Yes it was... But without the additives

 

[winch2]

Yes it was... But without the additives

And if my schoolboy geology is correct, also devoid of any H20.. too.

 

[jdc]

And if my schoolboy geology is correct, also devoid of any H20.. too.

I think the school didn't really cover the subject fully. Oil and gas reservoirs are traps in in the rock with an impervious layer above (usually shale), so the tiny amounts of oil or gas created by anaerobic decay rise through the water in the water saturated sedimentary rocks until trapped. Below the oil there is always water, and the boundaries not so clear cut. In fact, when extracting oil from a well you have to be very careful not to draw it out too fast lest you get lots of water with it.

More relevant is that the oil lay for eons in anaerobic conditions - entirely without Oxygen - and that's certainly not the case when sitting in a plastic container!

 

[38mess]

I think the school didn't really cover the subject fully. Oil and gas reservoirs are traps in in the rock with an impervious layer above (usually shale), so the tiny amounts of oil or gas created by anaerobic decay rise through the water in the water saturated sedimentary rocks until trapped. Below the oil there is always water, and the boundaries not so clear cut. In fact, when extracting oil from a well you have to be very careful not to draw it out too fast lest you get lots of water with it.

More relevant is that the oil lay for eons in anaerobic conditions - entirely without Oxygen - and that's certainly not the case when sitting in a plastic container!

So I can use it then

 

[jdc]

I'd use it with no worry. Just being pedantic about H₂O vapour not being a worry when stored. I don't suppose Oxidation of the additives is an issue either provided it's been kept in a bottle or can and stored at room temperature.

 

[B27]

I'd imagine it is a date and time of packing.
People do this to aid traceability in case there is a problem with a batch or something.
And to enable people to use the oldest first.

Some oil products do have shelf lives.

 

[capnsensible]

bought some oil for my engine a few weeks ago, 15-30 semi synthetic, and today I noticed a date on the nozzle of 12/12/21...03.35am.
I take it that's the manufacture date and not the expiry date?.

Simply do the taste test. Take an eggcup full and down it in one. If it tastes like oil, it's fine. If it tastes like anything else, bin it.

 

[38mess]

Simply do the taste test. Take an eggcup full and down it in one. If it tastes like oil, it's fine. If it tastes like anything else, bin it.

I can't imagine why I didn't think of that, just off to have a swig