QUESTION: Oil additives VS Oil brand?

[Showboatsix]

QUESTION: Since some in here do not like additives added to oil or gas, which brand of oil do you use, or which brand is better for use in an aircraft engine.

Since aircraft engines have not evolved much since 1933, and the oil market has, which "modern" oil should we be using in our "antique" engines?

What really is the difference between "Aircraft oil vs Automotive oil"? Lets really look at the oil itself and not just "because" we are suppose to use it argument.

Remember that just because the FAA says to use or not to use does not normally make it right. (remember, the brass float, composite float, back to the brass float fiasco).

[GAHorn]

Automotive oil contains additives that are unacceptable in aircraft engines. Some of them produce ash that adversely affect the engine's combustion chambers and can cause pre-ignition which in turn can damage the engine.

Also some of the additives will definitely damage aircraft engine parts. Example: Zinc additives (common in auto oils in the form of zinc dithiophosphates) attack some aircraft engine bearing materials, especially thrust-bearings and those with silver alloys. It can lead to failure in short order.

I have to admit that it puzzles me when we think that just because "oil technology" has progressed to some more "modern" products..... that it's applicable to put that product in an engine which has not been changed to utilize that technology. Similar logic would tell us it's OK to put jet fuel in piston engines and Coleman Fuel in woodstoves.

I use AeroShell 100W in summer and 80W in winter.

[Showboatsix]

I switched from that oil because it failed in every test.

See link to test results: http://www.castrolaviator.com/north_ame ... ology.html

I now use Castrol Aviator for the last three years.

http://www.castrolaviator.com/north_ame ... ts.html#ad

[DaveF]

I use Exxon Elite. All my oil analysis numbers dropped when I started using it about six years ago. They have real test data to back up their claims.
http://www.exxonmobil.com/lubes/exxonmo ... elite.html

And even though I'm very skeptical of additives, I'm going to try Camguard, an anticorrosion/antiwear additive that was developed by the guy who, when he was with Exxon/Mobil, developed Elite.
http://www.aslcamguard.com

[GAHorn]

They'd be a lot more convincing if they named their competitiors and used an independent lab to run the tests. Aviation Consumer, who had no dog in the fight, tested all these products and concluded that single-grade Aeroshell AD oils (not the "Plus") was the best performer of all the oils tested.


As for Castrol, in their own opening words of their "test" results (in which they do not identify the "competition") :"
"Anyone can tell you their products are the best. But do you necessarily believe them? "

Elite contains phosphorus, as does Aeroshell "plus", both bad for copper bearings and bronze valve guides and bushings. I have just finished examining spectroanalysis lab reports of a member who has a sudden large increase in copper in his oil analysis. He wondered why.

Here's the pertinent commentary from the laboratory:
"This sample looks better than the last, though that's probably due to the shorter oil run more than anything else.
Most metals dropped, though copper actually increased a little. On a per-hour basis, copper got worse, and we are
concerned about exhaust valve guides in this engine. As you know, copper can be from any bronze or brass
part, though valve guides are often the culprit. Watch for metal in the filter and keep the oil changes at 20-25
hours for now."

He copied me in on the report and asked my opinion. I examined the analysis report. The analysis shows that at exactly 401 hours his copper levels increased, and the laboratory was commenting on that. I noticed something that, quite frankly, I was very surprised the laboratory had said absolutely nothing about! In all previous samplings there was NONE of something... that suddenly there was a LOT of-------PHOSPHORUS! 621 PPM of phosphorus where there had never been any before showed up in the same sample that had the laboratory very worried about increased amounts of COPPER!

I advised our friend that I was suspicious, and asked him a question: Had he recently switched oil brands?

His answer came back: Yes! At 401 hours, he'd just switched to a different brand in the sampling-period being addressed with the high copper AND high phosphorus. He'd just switched to....... Exxon Elite.

[DaveF]

That is certainly a compelling story, but my oil analysis results are just as valid as your friend's. All numbers went down or stayed unchanged. That included Fe, Ni, Al, and Cu. The bronze and brass parts did not turn to Jell-O. And the engine, a TSIO520R, was running well at 1400 SMOH when we sold the airplane, with no major engine work required in ten years other than four exhaust valve guides. No bottom end or turbo work, pretty good for a T210.

But mine is just one more anectodal story that proves nothing. The real question is whether we should keep doing what guys did back in the '50s, just because it worked for them. Chemistry, metallurgy, and engineering have progressed since then and I think it's possible that a better engine oil has been developed in the past 60 years. I'm willing to look at the developers' claims and try to overlook the sales hype.

[GAHorn]

That is certainly a compelling story, but my oil analysis results are just as valid as your friend's. ....

He is not just my friend. He's one of our own fellow-members.

I wonder what "Chemistry, metallurgy, and engineering" changes have occured in our 50 year old engines that would benefit from "modern, high-technology" lubrication? To my thinking, they should receive what they were designed for....single-weight, mineral oil, with few additives.

Phosphorus additives are known to attack copper. They are especially aggressive during storage periods of non-use (such as the low-utility rates most pleasure aircraft experience.) They are beneficial in extreme-pressure gear applications, but our engines have no extreme-pressure components....all gear components being generously over-sized and low stress.
I think this subject proves that marketing works. (And that when considering the failure to influence behavioral change with fact and logic,... there's little difference between oil-brand loyalties and religion.)

If you are a TIC170A Member, you might enjoy reading the PDF file on OIls in the Members Issues section.

[Showboatsix]

My question is: how is it that there are 400 million+ automobile engines (at least) running between o and 100,000 miles on them and all of these "evil" oil additives do not dissolve the bearings, the valve guides, the gears, the pistons and all the other wear items in them, yet if they (evil oil additives) were used in an "aircraft engine" it would fall apart and fail in short order. (as some say)

So if the auto engines do not fail after 100,000 + miles and their bearings and thrust washers, and valve guides seem to be fine, then why in the hell are we still flying around with out of date, antique bearings and components in our aircraft engines? (Aircraft Kuality spelled with a K on purpose)

And don;t say that our aircraft engines are "stressed" so hard vs auto engines, my 0-300 has a whopping 7.1-1 compression ratio, and does not even make 1/2 HP per cubic inch (145HP @ 2700RPM), yet the Honda 1.8 liter engine (110 CID) in my kid's car has 11.5-1 compression ratio and makes 210 HP @9000RPM at the wheels, that's 1.9 HP per CID, I wonder which engine is more stressed between the two.

Is it possible that the very reason our aircraft engines have not progressed with times is because the FAA in their ultimate wisdom really restricts the development in GA aircraft engines and the ONLY area where development has occured is in the "expermental catagory" of aircraft! (hence the 180 HP, 0-200, 10.5 -1CR, in my buddy's EZ that he spins to 3300RPM for hours during races and he does that at full power)

Just wondering......... as I chug along in my C-172 thinking about all those parts wirling around at 2400RPM that are keeping me "between the here and the here after"!

[W.J.Langholz]

Maybe something like Miistral' G-300 would be nice. That engine should be 5-6k at the most if it wasn't going in aircraft....bet it will be 20k though.

[GAHorn]

(This is all just my opinion and has no more validity than any other person's opinion here. It's offered as a discussion only. Not intended to inflame or interefere in any owner's right to choose what he does with his own property.)

My question is: how is it that there are 400 million+ automobile engines ...

So if the auto engines do not fail after 100,000 + miles ...

And don;t say that our aircraft engines are "stressed" so hard vs auto engines, my 0-300 has a whopping 7.1-1 compression ratio, and does not even make 1/2 HP per cubic inch ...

Is it possible that the very reason our aircraft engines have not progressed with times is because the FAA in their ultimate wisdom really restricts the development in GA aircraft engines and the ONLY area where development has occured is in the "expermental catagory" of aircraft! (hence the 180 HP, 0-200, 10.5 -1CR, in my buddy's EZ that he spins to 3300RPM for hours during races and he does that at full power)..."!

Automobile engines are usually driven on a daily basis and use less copper-bearing materials, so additives like phosphorus are not especially hazardous to them. It's the engines which SIT for long periods that are most harmed by phosphorus.

The other additives are not used with leaded fuels, like aero engines are, which makes for a different chemistry,... AND the aero engines are AIR cooled and run at different temperatures, .... AND the aero engines run thru greater atmoshpheric changes during each cycle. There are too many DIFFERENCES in the two types of engines, that many just choose to ignore in their considerations, to assert that these sort of comparisons between auto and aero engines are valid.

Our aero engines ARE driven hard. (When was the last time you woke up your car and within a couple minutes gave it full throttle for 10 minutes and then ran it at 75% power for a few hours, then quickly reduced power and shut it down for another week?) The average car trip, even on the freeway, rarely uses more than 30% power. Even when we shoot into traffic and catch up, it's only demanding full throttle for a few seconds, then it loafs again at 30% or less for a few minutes, all while evenly keeping it's temperature and predictable specification with a thermostat and liquid cooling.

The "FAA in their ultimate wisdom" is not the enemy in this discussion. The aircraft is certificated at a certain point in time with a certain engine. So is the engine. It's the manufacturers of those products who do not wish to introduce changes in their products due to costs associated with the need to prove airworthiness of the changes. Would you really prefer that Continental make a design change and just throw it out there for you to innocently install at overhaul?* And would you actually be willing to PAY a big price increase for the new part versus the less-expensive part that had a little dust on it's box sitting there in the same parts-bin? (This is exactly the scenario that killed Mobil AV-1 synthetic oil! Not only did customers pay more for the aero-product that had been copied from automotive "modernity" .... that product... the "new and improved" ...."modern oil".... killed their engines!)

*And by the way, the overhaul that you might perform which incorporated the "modern" part.... when exactly would that occur? How often would: 1) You benefit from the improved part? .... and 2) would the mfr'r profit from it? ... considering that the average one of us has never overhauled our engines? The average Cessna 170 goes thru overhaul how often? ....say,...about every 20 years? If that? Wow, that certainly is a huge profit to be made by the engine mfr'r, heh?

Don't blame the FAA. They are the ones who have established and kept airworthiness standards alive in order to improve our surviveability rates. If it weren't for FAA the lawyers would have all our widow's inheritances.

I use Exxon Elite. All my oil analysis numbers dropped when I started using it about six years ago. They have real test data to back up their claims.
http://www.exxonmobil.com/lubes/exxonmo ... elite.html

And even though I'm very skeptical of additives, I'm going to try Camguard, an anticorrosion/antiwear additive that was developed by the guy who, when he was with Exxon/Mobil, developed Elite.
http://www.aslcamguard.com

An important difference encountered when comparing oil analysis from one airplane to a different airplane's analysis is that such comparisons ignore TREND.... which is the main strength of analysis programs. YOUR copper levels isn't concerning you because YOUR copper is always being attacked on a regular basis. You have accepted whatever copper levels are displayed as a norm ....because there is no sudden CHANGE in TREND to raise a warning flag. Our fellow member's experience was significant in that the copper level was noticeably greater when he changed to an oil which had a different additive package, thereby supporting the prediction that oils with phosphorus will damage your bearings.

As a dear friend once pointed out: When one relies upon advertising claims as "tests".... one beleives the "results". Show me some independent lab tests and then we'll see how these product claims hold up. (Labs are not "independent" if they are hired by the promoter of the product to prove the marketing claims.)

What would you expect to prove by "trying" Camguard? Ask yourself, "What's the BEST that can happen?" That no catastropic failure occured which wouldn't have occured anyway? (Our O-300 engines do not have high-friction or wear at the cams like auto engines do. For that reason, the product will not likely do anything for you in any measureable way, but it will alter the chemistry of your engine in ways that are unpredictable. Unless, of course, you already use the oil the same guy already developed that already has the chemical that is already eating your copper. Ask yourself, "What's the WORST that can happen?" Hmmmn. (Another axiom comes to mind: "If it ain't broke......"

(This is all just my opinion and has no more validity than any other person's opinion here. It's offered as a discussion only. Not intended to inflame or interefere in any owner's right to choose what he does with his own property.)

[DaveF]

You can't say my copper was already being attacked because you don't know what oil I was using before switching to Elite. In fact, it was Aeroshell 100.

What's the best that could happen? I could get another 1000 hours out of my engine. Of course, I will never be able to prove that a different oil or additive was responsible for my achieving or failing to achieve that goal. But the day my tach hits that magic number, I'll be in your face here on the forum!!

[lowNslow]

He copied me in on the report and asked my opinion. I examined the analysis report. The analysis shows that at exactly 401 hours his copper levels increased, and the laboratory was commenting on that. I noticed something that, quite frankly, I was very surprised the laboratory had said absolutely nothing about! In all previous samplings there was NONE of something... that suddenly there was a LOT of-------PHOSPHORUS! 621 PPM of phosphorus where there had never been any before showed up in the same sample that had the laboratory very worried about increased amounts of COPPER!

I advised our friend that I was suspicious, and asked him a question: Had he recently switched oil brands?

His answer came back: Yes! At 401 hours, he'd just switched to a different brand in the sampling-period being addressed with the high copper AND high phosphorus. He'd just switched to....... Exxon Elite.

I have two comments on the above. One, I agree with DaveF comment regarding the validity of your conclusion based on one aircrafts one report. If this really is a problem why aren't the companies that do the analysis start warning aviators about these additives based on their findings. There are other causes of copper corrision and one of the most active is sulfuric acid which a product of combustion. As you state, oil analysis is a "trend" indicator so without some real history on not only this aircraft but many others and the effects of additives, I think it is hard to make any conclusions.

The other point is IF these additives provide any corrosion protection for other metals (and I don't know that they do), maybe it is a better choice to use them and protect your cylinders, cams, etc. if you live in corrosive enviorment and the airplane has long sits. Rust on cylinders walls and cams wears down an engine very rapidly as well, so even IF you have some copper corrision in the long run you might be better of with the additive.

[GAHorn]

You can't say my copper was already being attacked because you don't know what oil I was using before switching to Elite. In fact, it was Aeroshell 100. ...

My comment was based upon your statement that you'd switched to Elite six years ago, leaving the impression we were discussing an engine you were 1) presently operating and 2) had been operating on Elite for six years. You didn't supply the rest of the information you now offer.

My position is that phosphorus attacks copper (proven by many labs and independent tests) and that some oils (Plus and Elite and perhaps some others) have phosphorus.

Re: the camguard "What's the BEST that could happen?" I'm thinking the BEST that could happen is that your engine would continue to operate normally until it was time for overhaul, just exactly like it would normally. It would then be overhauled and sent thru the cycle again. And your wallet would be lighter for purchasing additives that likely had nothing to do with it.
On the other hand, that product would introduce a new variable into the operating environment of your engine, having the effect of providing a new level of interest in wondering what's going on in there? and for how long will, hopefully nothing, go wrong? The maker of the product is the only one who is guaranteed to benefit.
The state lottery has better odds.

[GAHorn]

...One, I agree with DaveF comment regarding the validity of your conclusion based on one aircrafts one report. If this really is a problem why aren't the companies that do the analysis start warning aviators about these additives based on their findings. ....

Some of the labs do exactly that. (It's the reason Aeroshell "PLUS" was exposed for copper erosion due to phosphorus.) Just because some labs do not mention it ...is more a reflection upon their policy of not attacking specific products (fear of lawsuits from the oil-makers?...) than it is a failure to mention the cause of copper erosion. They can comment on the increased level of copper ( as the laboratory mentioned did...) without exposing themselves to the risk of a lawsuit from a major oil company. Aviation Consumer produced a study on the phosphorus issue a couple of years ago, in which the results warned of the "plus" and the "elite" oils. Aeroshell reduced the amount, and Elite recalled their product and then re-introduced it with a different formulation and a promotional give-away. It still has phosphorus, however.

...The other point is IF these additives provide any corrosion protection for other metals (and I don't know that they do), maybe it is a better choice to use them and protect your cylinders, cams, etc. if you live in corrosive enviorment and the airplane has long sits. Rust on cylinders walls and cams wears down an engine very rapidly as well, so even IF you have some copper corrision in the long run you might be better of with the additive.

This is exactly the point made in the Aviation Consumer and the TBO Advisor reports, ... that these additives actually do more harm than good. Those articles demonstrate that the best protection against rust for airplanes that sit is not additives, but instead is actually straight-weight oil.

[Showboatsix]

Well I would have to say we have "beaten this subject to death", speaking of death, I am about to turn 60, so it occurred to me that I have more days behind me than in front of me.

Why am I bringing this up, well I am a pilot, and in front of me is an engine that is also 60 years old, I know what I look like in the mirror, and the last time I saw an airplane engine apart, I saw, connecting rods right out of a Model "T", pistons that weighted four pounds each, cylinders that were from a Wisconsin industrial engine, a camshaft that looks just like one from a Briggs & Stratton engine (only longer), a crankshaft that looks like a bent piece of spagehiti, a carburetor off of an Allis Chalmers tractor, magnetos from an old Oliver tractor, and spark plugs that have not changed since the first one was ever produced!, so as I fly I can not help wonder which one of these "fine Aircraft Kuality" parts is going fail first and do me in?

In my opinion (and we all know what opinions are like ), the reason we have 60 year old engines instead of modern ones are two reasons "the FAA and LAWYERS"! Porsche tried to make a modern airplane engine, and many others from Europe have also, (remember the "Voyager water cooled engines) all of them have pulled their attempt from the USA market, (again the FAA and LAWYERS hampered them).

As long as we have LAWYERS and the FAA making it absolutely impossible to bring into the "certified" market a new engine design we will always be flying behind 60 year old engine designs!

And that is my opinion!

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