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What's the best oil for your engine?

f14av8r

Well Known Member
One of my objectives for Oshkosh was to determine what oil I should be using in my engine. I attended every lecture on the subject that I could find and talked to the experts at the Aeroshell and Phillips booths.

Prior to Oshkosh, I read and was influenced greatly by reading Mike Busch's new book "On Engines." In his book, Mike unequivocally states his advocacy for single weight, mineral based (no synthetics) oil for owner-operated airplanes. He believes that the heavier weight, single weight oil coats the engine parts better and longer than does a multi-grade oil. A longer coating is an advantage for an owner-operated airplane that may sit for days or weeks without flying.

I was prepared to go with Mike's suggestion and switch from Phillips XC 20-50 to Aeroshell 100W at my next oil change. Then I went to the Phillips guy's forum. The Phillips guy, Steve (I forget his last name), provided some compelling data to show that a multi-weight oil (like XC 20-50) coats the engine parts as well as a single weight oil after 48 hours. And, he made a compelling argument that a multi-weight oil is better is most other respects than a single weight oil.

After his lecture, I questioned Steve during the Q&A and again one-on-one about his obvious difference with Mike Busch. Steve said he is a big Mike Busch fan but, on this one issue, he completely disagrees with Mike and thinks he is just flat out wrong.

So, now I'm on the fence again. Which oil should I be using. I fly in Florida the vast majority of the time, seldom experience temperatures below 60 degrees, and generally fly at least once a week.

I'd appreciate your thoughts on the subject.
 
Best Oil

During break in. 100% mineral oil Philips SAE 100. No additive.

After Break in. Non-Synthetic. So 100% mineral oil: Philips 66 XC Aviation SAE 20-50 with an additive like Camguard or Avblend.

Some really like Aeroshell multi-viscosity. Its like religion and politics.
 
During break in. 100% mineral oil Philips SAE 100. No additive.

After Break in. Non-Synthetic. So 100% mineral oil: Philips 66 XC Aviation SAE 20-50 with an additive like Camguard or Avblend.

Some really like Aeroshell multi-viscosity. Its like religion and politics.

Another interesting thing that the Phillips rep, Steve, said was that there was no reason not to run XC 20-50 for break-in oil. He said using an additive based oil made no difference for break-in and the only reason they even offer a 100% mineral based oil with no additives is just because Lycoming still calls for one.
 
Don't overlook the AeroShell Plus Oils (W100 Plus and W80 Plus) and AeroShell W15W50 multi-vis oil. They both have the Lycoming LW 16702 anti-wear and anti-corrosion additive. Note that this additive is not the same as CamGuard, and does not replace its use, for those who like using it.

More info:

https://www.shell.com/business-customers/aviation/aeroshell/piston-engine-oil/about.html

Steve, the Phillips guy, said the Aeroshell Plus products were fine except for the multi-weight which is only offered in a synthetic blend. Both the Phillips guy and Mike Busch say synthetics of any type are a bad choice for piston aircraft engines. I won't go that route. I'll either use AeroShell 100W or 100W Plus or Phillips XC 20-50 (which is all mineral oil based). I'm simply trying to decide between those choices.

Steve, the Phillips guy, said that the Plus oils from AeroShell are equivalent to their XC 20-50 used with CamGuard. Or, he suggested using their XC 20-50 and their Anti-Rust Oil mixed in at 10%. Mike Busch likes CamGuard so I'll go that route. I'm simply deciding to take the Phillips guys word on multi-weight vs Mike Busch's word on single weight.

Note, I did learn the the W after the oil number in a single weight oil has nothing to do with the viscosity of the oil. The W in 100W stands for additive, not weight / viscosity. The W in a multi-weight means the oil viscosity tested to Winter standards. Thus, the 15W50 multi-viscosity oil has been tested at those weights in winter conditions but the W says nothing about additives. All quite interesting!
 
Randy,
Whatever is easier to clean off the belly!

I'm running Phillips xc20w50 and Camguard. JB said keep doing what you're doing when he swapped my (perfect) Eci AD cylinders at 430 hours. Cam looked great. The new cylinders burn more oil though...:mad:
 
If you fly the plane regularly as a Floridian should, it won't matter which oil you use. I use Phillips 20W50, but have used Aeroshell 100W with good results. Fly the plane regularly, manage the engine wisely (for me, that means LOP), and change the oil every 25-35 hours (or 6 months whichever occurs first).
 
One of my objectives for Oshkosh was to determine what oil I should be using in my engine. I attended every lecture on the subject that I could find and talked to the experts at the Aeroshell and Phillips booths.

Prior to Oshkosh, I read and was influenced greatly by reading Mike Busch's new book "On Engines." In his book, Mike unequivocally states his advocacy for single weight, mineral based (no synthetics) oil for owner-operated airplanes. He believes that the heavier weight, single weight oil coats the engine parts better and longer than does a multi-grade oil. A longer coating is an advantage for an owner-operated airplane that may sit for days or weeks without flying.

I was prepared to go with Mike's suggestion and switch from Phillips XC 20-50 to Aeroshell 100W at my next oil change. Then I went to the Phillips guy's forum. The Phillips guy, Steve (I forget his last name), provided some compelling data to show that a multi-weight oil (like XC 20-50) coats the engine parts as well as a single weight oil after 48 hours. And, he made a compelling argument that a multi-weight oil is better is most other respects than a single weight oil.

After his lecture, I questioned Steve during the Q&A and again one-on-one about his obvious difference with Mike Busch. Steve said he is a big Mike Busch fan but, on this one issue, he completely disagrees with Mike and thinks he is just flat out wrong.

So, now I'm on the fence again. Which oil should I be using. I fly in Florida the vast majority of the time, seldom experience temperatures below 60 degrees, and generally fly at least once a week.

I'd appreciate your thoughts on the subject.

While the philips guy certainly has something of a bias, the fact is that oil manufacturers test things like cling rate in a laboratory. I feel confident that Mike does not have such testing equipment in his shop and is relying either on representations from others (source unknown) or very loose speculation based upon data seen at disassembly. However, seeing a spalled cam and directly correlating cause and effect solely to oil type seems more than a bit loose to me. For example, oil saturated with moisture can do as much or more damage than oil dripping off and leaving exposure to moisture laden air. much of the crank journal corrosion seen is of this type.

I would trust the manufacturers on an issue like this. You just need to separate out their bias and look at data.

In the end, I believe the camguard additives deliver superior cling rates over all traditional oil types (excluding those like Plus that have similar packages) and should eliminate the debate for you if you use it.

Larry
 
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Multi-weight oil by all means is the preferred choice for all my aircraft needs. All the oil manufacturers say the same thing that at an elevated temperature, the multi-weight oil will be thicker than the single weight oil.

I use Phillips 20-50M for break in, switch to Phillips X/C 20W-50 and still try to run 75% power or more for a total of 100-hours.

If not going to fly during the Winter, I switch to Phillips Anti-Rust. It is ok to use Anti-Rust for 10-hours as a break in oil or for up to 25-hours as long as you do not use it on the next oil change.

During the summer when not going to fly a lot on a regular basis, I prefer Aeroshell 15W-50 or one of the other multi-weight oils that meets the Lycoming AD requirement for better corrosion protection as it costs less than adding Camguard to Phillips X/C 20W-50.

IF you never fly in extremely hot weather with high oil temp plus fly an hour or more several times a week, any Aviation Oil of the recommended viscosity will serve you well. The key is, calibrated oil temp says 180-200 F and you fly often for more than a few minutes.
 
Randy,
Whatever is easier to clean off the belly!

I'm running Phillips xc20w50 and Camguard. JB said keep doing what you're doing when he swapped my (perfect) Eci AD cylinders at 430 hours. Cam looked great. The new cylinders burn more oil though...:mad:

Boy isn't that the truth Mike. But, thanks to my full Raven inverted system I'm not scraping as much as I used to!
 
http://www.vansairforce.com/community/showthread.php?t=76408&highlight=oil+additives

Check this thread. I personally go with Phillips XC 20w50 and recently started adding Camguard. I live in GA and it does get cold in the winter so I just stick with the same stuff year round. If I lived in Tampa, I would probably go with Aeroshell 100W and some Camguard since it never gets cold there. Just my .02

But why Mark. That's my question. Mike Busch says go with 100W but he says that primarily because he says the coating properties during periods of non-use are superior. The Phillips folks data says that isn't true.
 
Note: ECI cylinder install instructions say to use Philips 15W50 oil during break in. I use Philips 15W50 and some MMO for every oil change in a hopped up IO-360. Now my D17S... That's a whole can of worms.... I'm still trying to find out why AeroShell 120W is soooo expensive..
 
Note: ECI cylinder install instructions say to use Philips 15W50 oil during break in. I use Philips 15W50 and some MMO for every oil change in a hopped up IO-360. Now my D17S... That's a whole can of worms.... I'm still trying to find out why AeroShell 120W is soooo expensive..

Every oil expert, Phillips, AeroShell, and independent that I talked to said Marvel Mystery Oil is just that, a complete mystery and totally ineffective. According to most of them the only thing mysterious about MMO is the fact that intelligent people would spend any money for the product.
 
It all depends on who you ask.

I asked Mahlon years ago and he said to urn Philips 20W-50 from break in through the end of life and that is what I have done on both engines with no issues.

Then at some point I spoke to Allen Barrett and he said the cleanest engines he has disabled were those that run CamGuard, so I have started running that as well.
 
In Flordia, multi weight Rotella....

In Florida, I'd probably go with Rotella non-synthetic 15w40 and maybe add camguard to make ya feel better. Of course you may want to top it off with AVBlend for icing on the cake.
 
Heck, this is 2018.....

When our ditch pump engines were developed in the 30's, the only oil available was distilled tar with clay and stuff in :D

Nowadays, things are different and for decades, the major oil companies have been supplying multigrade oils which offer both low viscosity for starting and high viscosity characteristics for protection between runs and at higher temperatures.

I would no sooner run single weight oil in my Lycoming than run mogas, but that is a complete thread drift, so we won't go there ;)

Stick with multigrade and if Camguard gives you peace of mind, add it. Easier, cheaper and way more fun is to just GO FLY !!!
 
FWIW......

Back on 12-18-12 I cut three sections of ordinary mild steel strap from the same piece, bead blasted them nice and clean, and drilled a hole in each.

The first was dipped in Aeroshell 15-50. The second was dipped in straight Phillips 20-50. The third was dipped in Phillips 20-50 mixed with the recommended quantity of CamGuard.

Corrosion%20Samples%20Start.jpg


They spent the first few weeks hanging outside the shop (above) so the oil would have plenty of time to run off, just like inside a parked engine. Then I laid them flat on top of a handy landscape timber and left them a few more weeks.

Here they are on 1-29-13, a little over 6 weeks later:

Corrosion%20Samples%20End.jpg


Frankly, I don't see a heck of a lot of difference, between samples, or between the upper (uncoated) and lower (oiled) half of each sample. They seemed to develop rust pits at the same rate throughout the exposed period.

Somebody do the same test incorporating a straight weight oil, and maybe we'll learn something useful.
 
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FWIW......

Back on 12-18-12 I cut three sections of ordinary mild steel strap from the same piece, bead blasted them nice and clean, and drilled a hole in each.

The first was dipped in Aeroshell 15-50. The second was dipped in straight Phillips 20-50. The third was dipped in Phillips 20-50 mixed with the recommended quantity of CamGuard.

Corrosion%20Samples%20Start.jpg


They spent the first few weeks hanging outside the shop (above) so the oil would have plenty of time to run off, just like inside a parked engine. Then I laid them flat on top of a handy landscape timber and left them a few more weeks. They are offering an improvement over stock oils, but not a long term panacea.

Here they are on 1-29-13, a little over 6 weeks later:

Corrosion%20Samples%20End.jpg


Frankly, I don't see a heck of a lot of difference, between samples, or between the upper (uncoated) and lower (oiled) half of each sample. They seemed to develop rust pits at the same rate throughout the exposed period.

Somebody do the same test incorporating a straight weight oil, and maybe we'll learn something useful.

An interesting test and strong evidence that nothing oil based is going to stop rust over the long haul when exposed to the elements. However, even camgaurd doesn't suggest protection in excess of thirty days. They claim that most stock oils protect for only a few days, while they can go a month. Here is data from their test

humiditycabinettesting.jpg


Not necessarily trying to advocate for camgaurd, but wanted to put this data in perspective with your test.

Relevant to the initial thread intent, multi-vis and straight oils performed identically without the camgaurd.
 
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Every oil expert, Phillips, AeroShell, and independent that I talked to said Marvel Mystery Oil is just that, a complete mystery and totally ineffective. According to most of them the only thing mysterious about MMO is the fact that intelligent people would spend any money for the product.

Haha.. Experts = BS.. They are all biased. They either work from a company or they believe they are important. As far as MMO? I've seen it work. Years ago I had a Turbo Arrow with a low cylinder, added 1/2 qt MMO and the compression came up within a few hours F/T. I've seen MMO loosen a frozen Briggs & Stratton. Story after story from friends and pilots about MMO working magic. The mystery is why people like you only believe "Experts" that have a stake only in their product. I'm sure you have no idea the history of MMO. Might want to look that up.

Not only do ALL the oil companies and the additive companies have their own "Test Labs" but they ALL test so their products produce the results they want. Change the temps, change the pressures, change the weight, change anything they want to say what they want. The only requirements of oil is that it must pass SAE standards, nothing more. Anyone remember when the audio companies stopped using Output Watts RMS to state the power output of an amplifier? The wild output claims that every audio company made after that was a joke. Don't be so gullible.
 
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Haha.. Experts = BS.. They are all biased. They either work from a company or they believe they are important. As far as MMO? I've seen it work. Years ago I had a Turbo Arrow with a low cylinder, added 1/2 qt MMO and the compression came up within a few hours F/T. I've seen MMO loosen a frozen Briggs & Stratton. Story after story from friends and pilots about MMO working magic. The mystery is why people like you only believe "Experts" that have a stake only in their product. I'm sure you have no idea the history of MMO. Might want to look that up.

Not only do ALL the oil companies and the additive companies have their own "Test Labs" but they ALL test so their products produce the results they want. Change the temps, change the pressures, change the weight, change anything they want to say what they want. The only requirements of oil is that it must pass SAE standards, nothing more. Anyone remember when the audio companies stopped using Output Watts RMS to state the power output of an amplifier? The wild output claims that every audio company made after that was a joke. Don't be so gullible.

Now don't go gettin your panties in a wad. I was just passing along what I heard in the lectures. I'm still trying to form an opinion which is why I asked the question. If you think MMO is the cat's meow, I value that feedback. Nobody else seems to think so but, if it worked for you, I appreciate your offering your experience.
 
If you think MMO is the cat's meow, I value that feedback. Nobody else seems to think so but, if it worked for you, I appreciate your offering your experience.

There are others that use and appreciate MMO; a few years ago I had a stuck exhaust valve. The crusty, err, experienced mechanic that fixed it recommended that I run MMO in the gas to help keep the valves and stems clean; it seems to be working for me so far. I also see many radial engine Warbird types doing the same... it?s gotta be the lovely wintergreen scent that?s the effective ingredient here.
 
I'm an A&P, just getting ready to test for IA. I know plenty of A&P's and IA's, every one of them recommend using MMO. The military kept tons of 55 gal barrels of MMO at all the airfields. Note: Does the name Marvel ring any bells? How about Marvel Shreiber? A whole lot of you guys are flying with one. Yes, he invented Marvel Mystery Oil... Very interesting story. 100's of 1000's of military pilots and mechanics all agree MMO worked. Sorry, I don't blindly follow the "Experts".
 
Just a quick comment / observation. When I last took an engine in for overhaul the shop disassembled the engine right in front of me so I could have a good close look at its status and a much better idea of what the overhaul was going to cost.

When the engine had been torn down I noticed gold-coloured deposits in the engine. Sort of like the appearance of the foil insulation in airliners before smoking was banned - a gold haze over everything. The overhaul shop manager asked me if I ran AeroShell oil. Of course I did!

He then showed me an engine in a similar state of tear down, and its interior metal surfaces were shiny silver metal like a new engine. That engine had gone to TBO running Phillips XC 20W50.

When it came time to spark up our brand new Lycoming O-360-A1F6 I remembered those gold deposits in the engine and started the break-in process using Phillips XC 20W50, and continue to run it today. Break-in was uneventful, despite frigid winter temperatures. Oil consumption now is about a quart in 20 (or more) hours, and the filter remains clean of any debris.

I know precious little about petroleum products so that little side-by-side comparison of an engine that had run AeroShell and an engine that had run Phillips was an education for me.
 
getting a headache

Interesting thread, I followed ECI's guidance for my 0-360 break-in and have run Phillips XC 20/50 ever since with the addition of camguard and some MMO in the gas. The oil sample analysis from Blackstone can be summarized as "keep doing what you are doing".

I guess the question for us non experts is what would we keep our eye open for to suggest the need to change an approach that seems to work?
Figs
 
When the engine had been torn down I noticed gold-coloured deposits in the engine. Sort of like the appearance of the foil insulation in airliners before smoking was banned - a gold haze over everything. The overhaul shop manager asked me if I ran AeroShell oil. Of course I did!

He then showed me an engine in a similar state of tear down, and its interior metal surfaces were shiny silver metal like a new engine. That engine had gone to TBO running Phillips XC 20.

Which Aeroshell, and why is gold coloration bad? Any component damage or excess wear?
 
I don't recall seeing this before, but those considering using MMO might want to at least read this NTSB report:

https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20020916X01610&key=1

Skylor
You might want to read a *lot* more NTSB reports, for some perspective, before attaching any real significance to this one. 1st it wasn't an airliner. 2nd, well, it wasn't an airliner. Reservoir of expertise: Exhausted.

Inevitable conclusion as to cause: Whatever (or the 1st thing noticed, that) was unfamiliar to the examiner.

Charlie
edit: I suppose I should add a ;-)
 
NTSB report

Interesting conclusion reached based on what is written:
1) Tanks were all full
2) No mention of which tank was feeding the engine at loss of power
3) No mention of the actual ratio in the MMO tank
4) Low compression and leaking valves in all cylinders and evidence of detonation but no analysis of MMO being the cause of any of those symptoms
5) Net result was MMO caused the problem??????
 
Dan - to answer your question, the engine that ran to TBO (and actually quite a bit beyond, being flown "on condition") was a flight school O-200 from a C-150. Mine was a C85. The Aeroshell that was used in mine was 15W50, but previously it had run with W100. The O-200 reportedly had been run with Phillips XC 20W50 since break in.

To be fair, my engine bottom end was in need of overhaul but I purchased the airplane without any logbooks so I had no real history on the engine, thus no idea how many hours were on that bottom end when inability to maintain oil pressure caused the engine to be removed for overhaul.

Comments from the overhaul shop indicated the gold colouration likely wasn't harmful, however they did say they have had better luck with the longevity of oil pump gears with Phillips. Of course there was no data shared to quantify or otherwise support this sentiment. They did say the gold residue made it much more difficult to detect cracks and that bead blasting or other techniques were required to remove the gold stuff to reveal the true nature of the metal beneath. Perhaps this is a word in favor of the AeroShell as that gold coating might also have helped in plugging up potential leakage paths!
 
I don't recall seeing this before, but those considering using MMO might want to at least read this NTSB report:

https://www.ntsb.gov/_layouts/ntsb.aviation/brief.aspx?ev_id=20020916X01610&key=1

Skylor

You can't regulate stupid. If the fuel was pink and oily the guy must of had a 50/50 ratio of fuel and MMO... And again, the report doesn't say which tank the plane was on or any info on how the long the engine was in service or log entries. MMO is not a fuel, I think we can all agree to that. I'm sure the FAA prohibits the use of water as a fuel, too.
 
FWIW - I spoke with the Aeroshell folks at Oshkosh about using Camguard. They said not to use it with Aeroshell 15W50 as it already has the Lycoming protective ingredients. Same for Aeroshell 100W. They said Camguard is fine with Aeroshell 100, and I understand from Mike Busch and others it should be used with Phillips 20-W50.
 
Reluctant post here:

I do NOT want to start a war here, but a dear friend of mine (now passed) actually got a Phillips oil engineer to talk to him about this subject. After swearing to not tell anyone, the fella said to MIX 25% Phillips 20W-50 with Phillips X-CY 20W-50. If I can recall, the synth was better for preventing rust, and kept things cleaner.

My preference is to use 25% Amsoil 20W-50 as it is a known ashless-dispersant oil, so that product is what I mix in with X-CY.

I do not know if the Phillips auto 20W-50 is ashless-dispersant.
 
FWIW - I spoke with the Aeroshell folks at Oshkosh about using Camguard. They said not to use it with Aeroshell 15W50 as it already has the Lycoming protective ingredients. Same for Aeroshell 100W. They said Camguard is fine with Aeroshell 100, and I understand from Mike Busch and others it should be used with Phillips 20-W50.

I think the designations might be a off a bit here. Aeroshell 100 is a single weight straight mineral oil, not ashless and with no dispersants. It shouldn't be run regularly in an engine using leaded fuel like 100LL. Aeroshell 100W is a straight weight ashless dispersant oil. The W signifies Ashless / Dispersent when used in a straight weight commercial designation. Aeroshell 100W Plus is also a straight weight ashless dispersant and additionally has the Lycoming additive package. The 100 oils are all SAE 50 equivalents. Confusing I know!

Aeroshell 100W can, and from what I've learned, should be operated with an additive like CamGuard. IF you use Aeroshell 100W Plus, using Camguard would be redundant.
 
Synthetic oils will not suspend the lead in our AV fuel, that's why you can't use 100% synthetic. Works just great for cars and unleaded. Some time back Mobile 1 was tried to market aviation Mobile 1 and failed. A few companies attempted to produce 100% synthetic and failed. I see no reason to run any amount of synthetic on engines that were designed decades before synthetic oil was ever marketed. For most of us that change our oil every 25 ~ 50 hours synthetic just makes your wallet lighter with no benefits.
 
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Synthetic oils will not suspend the lead in our AV fuel, that's why you can't use 100% synthetic. Works just great for cars and unleaded. Some time back Mobile 1 was tried to market aviation Mobile 1 and failed. A few companies attempted to produce 100% synthetic and failed. I see no reason to run any amount of synthetic on engines that were designed decades before synthetic oil was ever marketed. For most of us that change our oil every 25 ~ 50 hours synthetic just makes your wallet lighter with no benefits.

Well said. As I understand his writings on the subject, this is why Mike Busch definitively says AeroShell 15W50 is a poor choice. He doesn't like multi-weights either (for warm climate use) but disapproves of the use of any synthetic.
 
I think the designations might be a off a bit here. Aeroshell 100 is a single weight straight mineral oil, not ashless and with no dispersants. It shouldn't be run regularly in an engine using leaded fuel like 100LL. Aeroshell 100W is a straight weight ashless dispersant oil. The W signifies Ashless / Dispersent when used in a straight weight commercial designation. Aeroshell 100W Plus is also a straight weight ashless dispersant and additionally has the Lycoming additive package. The 100 oils are all SAE 50 equivalents. Confusing I know!

Aeroshell 100W can, and from what I've learned, should be operated with an additive like CamGuard. IF you use Aeroshell 100W Plus, using Camguard would be redundant.

Thanks for the clarification. I should have taken notes when I talked to Aeroshell. The important part to me was he said don't use Camguard with 15W50 and 100Plus.
 
Maybe!

Synthetic oils will not suspend the lead in our AV fuel, that's why you can't use 100% synthetic.

snip

We all know about the Mobil 1 SNAFU, but keep in mind that Amsoil was developed as an ashless/dispersant aviation oil (or so I am told), and no known engine problems are blamed on that particular brand. The dispersant notation says that brand DOES suspend the lead.

I think the addition of some small percentage of an ashless/dispersant synth keeps the iron parts from rusting (well, more so than non-synth oils) but I have no proof of this, other than Exxon Elite semi-synth and their claims.

A peek inside of engines running some percentage of synth vs those not doing so could enlighten us, but danged if I know how to do that. I have one of those 'peek inside' cameras, but it surely does not produce pictures like we see in the ads...or it could be I'm not using it correctly?

The synth oils are not used on the round engines as they allow the cam roller followers to slide instead of rolling - bad juju there. I have also heard the main bearing does not like synth - I can't figure that one out. I always ran X-CY in my 985s and 2600s - no additives or synth added to the mix. Ever.
 
Oil

Ok from this thread I learned that Mike says don't use synthetic oil.And synthetic oil wont support the lead in 100LL.Our aircraft engines run very hot and its a proven fact synthetic oil protects much better at those temps while mineral after a certain temp provides less.Aero shell 15-50 is a blend of mineral and synthetic which carries the lead in suspension.I will be running full synthetic when the lead goes away.I was told at OSH that the FAA (Folks Against Aviation) had suspended testing unleaded fuel for a year so its going to be further down the road.From what I remember running Phipps X/C oil from break in to TBO was started by Ram aircraft engines on engines with nickel-silicon carbide cylinders which most of us don't run. The poster said that the TBO clean engine was a flight school engine run every day also a big difference in our engines.My question for Mr. Bush is where's the Beef?
Bob
 
I am in the process of switching to unleaded fuel (Swift 94UL) and I need to either use an oil that contains the LW-16702 Lycoming additive or add it directly, per Lycoming S.I. 1070Z. I have used Phillips 20w-50 for the 1550 hours since the overhaul. I spoke with Lycoming and Continental people at Oshkosh and the Continental people told me they have seen a marked increase in wear rates after switching oils after the engine has been in service for more than 500 hours or so. I was planning on switching to Aeroshell 15w-50 but I am now going to use the Phillips oil and the additive (or Camguard). Any extra cost will be more than offset by the cheaper fuel (.50 at our airport).
The Lycoming people at Oshkosh were unable to tell me why they require the additive with unleaded fuels but I will comply with S.I. 1070Z anyway.
 
We all know about the Mobil 1 SNAFU, but keep in mind that Amsoil was developed as an ashless/dispersant aviation oil (or so I am told), and no known engine problems are blamed on that particular brand. The dispersant notation says that brand DOES suspend the lead.

Same for Aeroshell multi.

A peek inside of engines running some percentage of synth vs those not doing so could enlighten us...

Way back in 1986, my roadracing Honda would strip the hardfacing off the highly loaded cam followers in a single weekend. Switching to a half synthetic oil ended the problem with no other changes. Made me a believer.

The synth oils are not used on the round engines as they allow the cam roller followers to slide instead of rolling - bad juju there.

Interesting. One might assume the problem would also exist with typical roller lifters in flat engines (and cars), but the radial parts are different. You figure the higher inertia of the large diameter roller makes it slide during acceleration on the gentle ramps of the radial's cam ring?

Regardless, it tells a tale about the lube film.
 
I am in the process of switching to unleaded fuel (Swift 94UL) and I need to either use an oil that contains the LW-16702 Lycoming additive or add it directly, per Lycoming S.I. 1070Z. I have used Phillips 20w-50 for the 1550 hours since the overhaul. I spoke with Lycoming and Continental people at Oshkosh and the Continental people told me they have seen a marked increase in wear rates after switching oils after the engine has been in service for more than 500 hours or so. I was planning on switching to Aeroshell 15w-50 but I am now going to use the Phillips oil and the additive (or Camguard). Any extra cost will be more than offset by the cheaper fuel (.50 at our airport).
The Lycoming people at Oshkosh were unable to tell me why they require the additive with unleaded fuels but I will comply with S.I. 1070Z anyway.

Did the Conti folks say why, or what was switched to what?

As for SI 1070Z, I don't think the additive requirement is specific to unleaded fuel. It's required with 100LL (see SI1409C) and auto fuel too. I think they were just heading off a future unleaded fuel FAQ.
 
The Lycoming people at Oshkosh were unable to tell me why they require the additive with unleaded fuels but I will comply with S.I. 1070Z anyway.

The additive in the oil is required by AD on the 76-series engines because of cam wear not the fuel.
 
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Well, that is rather disappointing, isn't it.

The one addition/change to this experiment that might be enlightening would be to change the surface finish of the samples.

Bead-blasting gives a pretty high surface-energy finish, very prone to rusting fast. And although the higher surface energy probably helps the oil film wet the surface, it is probably hard for the oil film to cover all the peaks.

A smooth ground surface would have lower surface energy and would perhaps help an oil film to stay longer, especially if it had some help in wetting the surface to start - wipe first, then dip.

I don't know that this would help or not.



FWIW......

Back on 12-18-12 I cut three sections of ordinary mild steel strap from the same piece, bead blasted them nice and clean, and drilled a hole in each.

The first was dipped in Aeroshell 15-50. The second was dipped in straight Phillips 20-50. The third was dipped in Phillips 20-50 mixed with the recommended quantity of CamGuard.

Corrosion%20Samples%20Start.jpg


They spent the first few weeks hanging outside the shop (above) so the oil would have plenty of time to run off, just like inside a parked engine. Then I laid them flat on top of a handy landscape timber and left them a few more weeks.

Here they are on 1-29-13, a little over 6 weeks later:

Corrosion%20Samples%20End.jpg


Frankly, I don't see a heck of a lot of difference, between samples, or between the upper (uncoated) and lower (oiled) half of each sample. They seemed to develop rust pits at the same rate throughout the exposed period.

Somebody do the same test incorporating a straight weight oil, and maybe we'll learn something useful.
 
The best oil is the oil that gets used regularly. My Cont-IO520 went 700 past TBO. Compressions were still in the 70’s but other things we’re wearing out.

Phillips XC20-50
Changed every 40 to 50 hours
No additives
Needed a quart added around 22 hours
LOP when traveling
FLOWN WEEKLY for ~ 30 minutes if not traveling
 
Cam gard

Cam gard sounds to me like good old fashioned STP, USED for years in our big block racers cause they only ran sparotically on weekends! Tomcat RV4
 
....The military kept tons of 55 gal barrels of MMO at all the airfields. ....100's of 1000's of military pilots and mechanics all agree MMO worked....

I was a flightline helicopter mechanic from 1968 to 1972, on helicopters using piston engines. There was never any MMO on the flightline nor available to us nor among the authorized fluids we had available. I was located at Edwards AFB, here in the U.S., not overseas, and sometimes went to other U.S. locations on temporary duty.

Dave
 
Mmo

MMO 2/3 solvent, 1/3 transmission oil. ( petroleum) Works great for loosening nuts,bolts etc.
Will I run it in my engine? NEVER
Please don’t listen to my opinion without looking it up thru there own MSDS.
 
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