What's new
Van's Air Force

The definitive Van's Aircraft support community! Buying, building or flying an RV? Join our exclusive family of mentors and enthusiasts!

"Old" oil?

R

rv7guy2

Active Member
I am getting close to swapping out the summer weight oil for cold weather oil in my IO-360 powered RV-7. I am currently running Shell W100 Plus and will be shortly switching to Shell W80+. for cold weather operations. (Ambient air temp below 10C, or 50F). I recently came into possession of two cases of Shell W80 that are dated "30May19." Is this oil still useable or is it time expired? Some local pilots have opinions both ways..some say use it, some say don't because it's 6 years beyond the stamped date.
What are your thoughts?
 
Try this prior discussion

Does Oil Expire?

At 12 hrs I used Aeroshell 100 Mineral Oil in the RV that I had left over from a TOH on the Champ 25 years ago. I figured a few more years on dead dinosaurs would have no significance. When I got the case I ordered this week it had a "Use By July 2020" date on it. Does oil expire? I've put a...
vansairforce.net

Does oil have a shelf life?

I bought six liters of Aeroshell Sport Four + oil for my Rotax 912ULS and RV12. I note that the bottles have two dates on them which are two years apart. There is no descriptor of the dates.....nothing to indicate what they mean. In my case the latest dates are two years ago. Does this cause...
vansairforce.net
 
For what it's worth I asked a similar question of the CamGuard rep at Oshkosh. He told me putting an expiration date on their product was mandated by the FAA. He said it was not tied to a shelf life or performance of their product.
 
Amadeus said:
How long was this oil underground awaiting discovery, drilling and pumping?
Click to expand...
Not the oil that’s the issue. It is all the additives and if they breakdown or stay in solution. Those additives are made in a chemical lab and not natural forming in Mother Earth.
 
mfleming said:
That's a joke...right?
Click to expand...
Why is that a joke? These oils have only the ad additive, nothing else (excluding the plus and victory stuff with the synthetic additives). The mineral oil base stocks are pretty much how they came out of the ground. Only real refining involved is separating the crude into various different weights/ aromatics. If it sat in the ground for 100’s of millions of years without degradation, what has changed? The bottle is sealed, so it can’t oxidize. What else is left to degrade the oil and make it unfit that wasn’t occurring for the last million years.

A lot of this expiration nonsense is just lawyers and marketing folks weighing in. Saw a bottle of my wifes eye drops. Ingredients listed as water and salt. Expiration date was two years out. I laughed and asked here to call someone and find out when the oceans are going to expire. Come on, saltwater expires???

Sure, there is plastic leaching into the fluidsover time, but that is limited to what we put in or on our bodies. Will have no effect on engine oil.
 
Last edited:
plehrke said:
Not the oil that’s the issue. It is all the additives and if they breakdown or stay in solution. Those additives are made in a chemical lab and not natural forming in Mother Earth.
Click to expand...
The only additive used in most aviation oils is ashless dispersent. The most common is PIBSI. It is considered very robust and highly stable and It fully mixes with oil and never falls out os suspension. While not a chemist, i have significant doubts that this will cause the oil to degrade, though in fairness, i do not know how long that additive will last before becoming ineffective. The fact that chemists consider it highly stable makes me think it is long lasting. If you are talking auto oils, that is a whole different matter, as they use a host of synthetic additives to meet their requirements.
 
lr172 said:
Why is that a joke? These oils have only the ad additive, nothing else (excluding the plus and victory stuff with the synthetic additives). The mineral oil base stocks are pretty much how they came out of the ground. Only real refining involved is separating the crude into various different weights/ aromatics. If it sat in the ground for 100’s of millions of years without degradation, what has changed? The bottle is sealed, so it can’t oxidize. What else is left to degrade the oil and make it unfit that wasn’t occurring for the last million years.

A lot of this expiration nonsense is just lawyers and marketing folks weighing in. Saw a bottle of my wifes eye drops. Ingredients listed as water and salt. Expiration date was two years out. I laughed and asked here to call someone and find out when the oceans are going to expire. Come on, saltwater expires???

Sure, there is plastic leaching into the fluidsover time, but that is limited to what we put in or on our bodies. Will have no effect on engine oil.
Click to expand...
Ahhhh no…our engine oils, sans additive, is not how crude oil comes out of the ground. Yes crude oil and engine oil have the word oil in them but crude comes out of the ground looking and acting nothing like engine oil. The crude oil is put through a process where the feed stock is separated into many products and engine oil ends up being just one of them. And it’s not just separation, it a chemical change to the molecules.
The lightest crudes can resemble gasoline and the heaviest crudes can resemble asphalt but none of them resemble engine oil until the refinery has done its job.
 
mfleming said:
Ahhhh no…our engine oils, sans additive, is not how crude oil comes out of the ground. Yes crude oil and engine oil have the word oil in them but crude comes out of the ground looking and acting nothing like engine oil. The crude oil is put through a process where the feed stock is separated into many products and engine oil ends up being just one of them. And it’s not just separation, it a chemical change to the molecules.
The lightest crudes can resemble gasoline and the heaviest crudes can resemble asphalt but none of them resemble engine oil until the refinery has done its job.
Click to expand...
I never said engine oil was the same as crude oil, only that it is separated out from crude oil, which is very old and therefore very stable. I don’t believe There are radical molecular changes going on in that process. Clearly there is some, as we start with one molecular structure (crude) and end up with many derivatives, but that doesn’t necessarily change the stability of the end product. We take salt water from the ocean, refine it to separate the water and the salt, a molecular change, and both of the separated products are just as stable as the source.

I am not a chemist, so clearly don't have the answers. I just don't accept it just because Philips wrote it on the bottle. we can agree to disagree on this.
 
Last edited:
You must log in or register to reply here.
Back
Top