oil shelf life

skidoo

skidoo

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skidoo
How long can Aeroshell 15-50 remain good on the shelf? Would you use some that was 10 years on the shelf?
 
All aviation oil now comes with a "sell by" date stamped on the case (but not the bottle). The FAA has recently been snooping around shops and lashing them if they have outdated oil on the shelf. However, the date is a very long way out -- like five years or more. Also, I've not heard of any consequences for individual owners who aren't keeping the cases to know what the "sell by" date is for the bottles in their hangars or baggage compartments. And, as Tom notes, there is no real evidence of which I know that "expired" oil is any less good than "unexpired" oil.
 
Ron Levy said:
All aviation oil now comes with a "sell by" date stamped on the case (but not the bottle). The FAA has recently been snooping around shops and lashing them if they have outdated oil on the shelf. However, the date is a very long way out -- like five years or more. Also, I've not heard of any consequences for individual owners who aren't keeping the cases to know what the "sell by" date is for the bottles in their hangars or baggage compartments. And, as Tom notes, there is no real evidence of which I know that "expired" oil is any less good than "unexpired" oil.
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Nice way to sell oil. After all, isn't the crude from which it is made some umpteen million years old.
 
Tom-D said:
Nice way to sell oil. After all, isn't the crude from which it is made some umpteen million years old.
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Perhaps the FAA owns stock in Shell, ExxonMobil, and Phillip Petroleum, because that's the only explanation I can think of for the FAA's position if it's only a "Nice way to sell oil." But I know a petrochemical engineer who used to do aviation products for a living, and I'll ask him for his opinion on that.
 
Ron Levy said:
Perhaps the FAA owns stock in Shell, ExxonMobil, and Phillip Petroleum, because that's the only explanation I can think of for the FAA's position if it's only a "Nice way to sell oil." But I know a petrochemical engineer who used to do aviation products for a living, and I'll ask him for his opinion on that.
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Do you recall what D-120 is ? we were burning it in 1970, from barrels that were canned in 1935.
 
Response from petrochemist:
Motor oil in a sealed container should be stable for several years. The
only reason I can see for dating it would be to determine whether an oil is
from a new formulation, since our aircraft oils don't have the SAE rating
circle like automotive oils. But even then, it's the date manufactured, not
expired, that matters.
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"Several years" is consistent with the "sell by" dates I've been seeing, so maybe there is a good technical reason for it -- long-term stability under unknown conditions of temperature, etc. Yes, you may find some oil from 1935 is still fine if it was never exposed to extreme conditions, but you might also find oil from ten years ago which has deteriorated due to exposure to extreme conditions. So, do you know where your oil's been?
 
Ron Levy said:
Response from petrochemist:
"Several years" is consistent with the "sell by" dates I've been seeing, so maybe there is a good technical reason for it -- long-term stability under unknown conditions of temperature, etc. Yes, you may find some oil from 1935 is still fine if it was never exposed to extreme conditions, but you might also find oil from ten years ago which has deteriorated due to exposure to extreme conditions. So, do you know where your oil's been?
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Suppose you purchased it 10 years ago and stored it in your unheated garage or hangar over that period, average temp 55 deg (low temp 33, high temp 105)
 
Ron Levy said:
Response from petrochemist:
"Several years" is consistent with the "sell by" dates I've been seeing, so maybe there is a good technical reason for it -- long-term stability under unknown conditions of temperature, etc. Yes, you may find some oil from 1935 is still fine if it was never exposed to extreme conditions, but you might also find oil from ten years ago which has deteriorated due to exposure to extreme conditions. So, do you know where your oil's been?
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I do, because the oil doesn't set around long.
 
Most likely an ISO/TS deal. I sell material that pretty much never goes bad, but the factory puts a 3 year shelf life on it for ISO/TS purposes. When asked, "why three years?", we were told, "We had to pick a number, so we picked three." One competitor happened to pick 5 years.

I've got customers that have used stuff that's 15 years old with no issues.
 
EdFred said:
Most likely an ISO/TS deal. I sell material that pretty much never goes bad, but the factory puts a 3 year shelf life on it for ISO/TS purposes. When asked, "why three years?", we were told, "We had to pick a number, so we picked three." One competitor happened to pick 5 years.

I've got customers that have used stuff that's 15 years old with no issues.
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I work in a warehouse with about 100,000 sq ft of space occupied by 'expired' product because the company decided that 2 years is a NRN (nice round number) to use as an 'expiration' date.

It worked out well for an international charity organization - I have sent off about 6 trailer-truck loads of the stuff to them as a donation so far this year, with another 4 truckloads sitting on the dock ready to go.

It started as a marketing tactic, but they didn't adjust their supply chain to deal with it... Surprisingly enough, they're talking about doing away with the 'expiration' dates on their product now.
 
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Ron Levy said:
I guess if you buy oil and it sits around for so many years the date on the box passes, you've made the error of buying and carrying excess inventory.
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If I change your oil, filter and use my shelf stock, you'd better replace it. or you get billed for the oil & filter at twice the price. I don't like chasing oil and other parts, that's is how you get stuck with the cost. and the shipping cost is getting stupid with haz/mat charges.

If you stop by for fuel, and need a Qt, I'll sell it to you for what it takes to get it here.

I stock 1 case of Phillips 20W50, 1 case of aeroshell 15W50. a few qts of aeroshell W80, All of which will turn over each year. So oil dating doesn't worry me too much. But I see no sense in it.

that is how it works at the little airport.
 
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Have you noticed there's an expiration date on bottled water? What's with that?

I have quite a bit of Shell Multi-Grade that has sat in an unheated hanger for about 15 years. Hope I'm not destroying my engine.

That oil from 1935 is probably just oil. Today's oils have much more exotic processing and lots of additives. I would think it's the additives that would expire if anything.
 
bsdunek said:
Have you noticed there's an expiration date on bottled water? What's with that?
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I read somewhere that the State of New Jersey requires all food products, including water, to carry an expiration date not longer than two years from date of manufacture.
That's why things like water and honey have an expiration date.
As for oil, I would guess that the manufacturers are thinking that consumers are so accustomed to "born on" dates and supposed "freshness" that they figure, "what the hell, let's slap a date on there." Why not?
 
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skidoo said:
How long can Aeroshell 15-50 remain good on the shelf? Would you use some that was 10 years on the shelf?
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A long time, and no, I wouldn't run it, but then I wouldn't run it if it was fresh either.
 
bsdunek said:
Have you noticed there's an expiration date on bottled water? What's with that?
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Ever tasted bottled water that's been sitting too long? My experience has been that it takes on a taste from the plastic. YUCK!
 
Oil thread!!

I had the same dilemma when I had to do a fluid replacement in the final drive of my BMW motorcycle. I had a 10 year old half full bottle of Mobil 1 75W-90 on the shelf. After a lot of discussions on the BMW board, I decided to use it.
 
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Ron Levy said:
Response from petrochemist:
"Several years" is consistent with the "sell by" dates I've been seeing, so maybe there is a good technical reason for it -- long-term stability under unknown conditions of temperature, etc. Yes, you may find some oil from 1935 is still fine if it was never exposed to extreme conditions, but you might also find oil from ten years ago which has deteriorated due to exposure to extreme conditions. So, do you know where your oil's been?
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What do you consider extreme temperatures? What's the decomposition mechanism?

I would use a old sealed container of oil.
 
Ahh Dinosaur vs Synthetic. Love those threads on ADV rider, and the other BMW boards. Always makes for entertaining reading. Sota the Motorcycle equivalent to the high wing low wing debate :D
 
Henning said:
The synthetic base stock used is not fully compatible with Avgas use. I'm not a fan of synthetics anyway, so I use Phillips 20-50.
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There is no such thing as a synthetic base stock, used in aviation oil.
 
flyingcheesehead said:
So.... Why don't you like Aeroshell 15-50, and what do you prefer and why?
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Because Aeroshell 15W50 has a additive package that contains a compound called Tricresyl Phosphate. (TCP) and other compounds to comply with Lycomings required AD to add the snake oil.

Continental engines do not require these additives. nor do they like it, Phillips 20-W-50 does not have that additive package.
 
Tom-D said:
Because Aeroshell 15W50 has a additive package that contains a compound called Tricresyl Phosphate. (TCP) and other compounds to comply with Lycomings required AD to add the snake oil.
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FWIW, Lycoming requires the LW-16072 additive only in the O-320H, O-360E, LO-360E, TO-360E, LTO-360E, TIO-541 & TIGO-541.

BTW, I was not aware that LW-16072 contains TCP. Do you have any documentation for that? Also, I've seen nothing to document any issues with using LW-16072 in an engine that doesn't require it. Again, any references would be appreciated.
 
From http://aeroshelldirect.com/aviation_oil.asp

Aeroshell Oil W15 - 50 is a premium semi-synthetic multigrade ashless dispersant oil specifically developed for aviation piston engines. AeroShell Oil W 15W-50 is a special blend of a high quality mineral oil and synthetic hydrocarbons with an advanced additive package that has been specifically formulated for multigrade applications. The combination of non-metallic anti-wear additives and selected high viscosity index mineral and synthetic base oils, give exceptional stability, dispersancy and anti-foaming performance.

So we do have semi-synthetic aviation oils. Further Googling found MSDS evidence of it as well.

From http://www.avblend.com/faa/kas_thomas_lenckite.html I find:
TCP Concentrate (the fuel additive from Alcor), is a prominent exception. The evidence is irrefutable, at this point, that TCP - by adding lead scaveniging - significantly improves spark plug life in engines that use leaded gasoline. As it turns out, tricresyl phosphate is also a good anti-scuff agent and therefore has a legitimate role in oil fortification. (Shell's use of TCP in 15W-50 Multi grade, and Lycoming's use of it in LW16702 oil additive, are 100% justified).

Dan
 
Dan Thomas said:
From http://www.avblend.com/faa/kas_thomas_lenckite.html I find:
TCP Concentrate (the fuel additive from Alcor), is a prominent exception. The evidence is irrefutable, at this point, that TCP - by adding lead scaveniging - significantly improves spark plug life in engines that use leaded gasoline. As it turns out, tricresyl phosphate is also a good anti-scuff agent and therefore has a legitimate role in oil fortification. (Shell's use of TCP in 15W-50 Multi grade, and Lycoming's use of it in LW16702 oil additive, are 100% justified).
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I would point out that to scavenge lead in your cylinders, the TCP must be added to your fuel, not your oil. If you want to do that, Alcor is the only supplier of TCP to be used as a fuel additive. IIRC, Aircraft Spruce has it.
 
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