Regulations Aside, Oil Discussion

weirdjim

weirdjim

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weirdjim
I really don't want anybody to come on here with hate and damnation that the rules are being broken. Thanks.

An old engine has a new oil filter system to replace the ancient screen out of the 1930s. Seems to me that "ashless dispersant" oil was intended to keep crap into solution until the oil change without filters. It didn't take into account the fact that oil filters may one day make their way into our ancient piston engines.

Given that oil has progressed over the last 60 years, if you were running an engine with a filter today, what oil would you choose and why?

Thanks,

Jim
 
Are you looking for specifics? I assume by your post that you already have another opinion? :) Short answer is it depends.
 
For my plane (Bonanza, IO520), in my geographic base (North Texas), I run AeroShell 100w, which (for reasons I still cannot fathom) is a 50 weight oil.

If I was in a older climate, I'd run a multi-vis oil. My plane does have a Tanis engine pre-heater, and I use it when it is cold.
 
I run mostly mogas in cold county so I run the semi synthetic Shell 15w-50 in my IO-540. In the summer I might run Shell 100w.

In the Rotax 912s I run the Shell Sport + 4 made specifically for Rotax with additives for the reduction gear box. I may switch to Mobile one this summer as I run no leaded fuel in it at all. Synthetic oil does not suspect lead and it settles to the bottom of the engine. Not good in a tight tolerance engine like Rotax.

Oil wars! Love them!

I highly suggest when attending Oshkosh or SnF that you go to the educational seminars put on by the oil companies. You will gain first hand professional knowledge about lubricating oils from lubrication engineers, not forum "know it all's". Please don't bring up Marvel Mystery Oil. The only mystery is why people keep using it. :lol:
 
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The AD keeps the junk in the oil not only so that it can be drained but so it doesn't just settle to the bottom of the pan. Besides, if it isn't in the oil how can the filter remove it?
 
I happen to have one of those engines. The E-185/225 Conti started life with a screen back in the early 40s. It also has a dry sump lube system for hiding goop in the corners of the tank. An externally mounted filter was added to the mix, and since then I've been running Phillips X/C 20-50. My plane lives in TX, but I make a fair number of trips to CO and other cold climates. So far, it's worked very well. Low oil use, good pressure and temps and the stuff is moderately cheap, in aviation terms when I buy it from the distributor in cases.
 
Not an opinion on oil but when a filter is added to an engine that originally did not have one and the original oil screen is not removed the result often is that the original screen never gets checked over a period of 20 years or so and that can eventually lead to trouble.
 
flyingmoose said:
Are you looking for specifics? I assume by your post that you already have another opinion? :) Short answer is it depends.
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I must have been too subtle. If I go into the aviation oil section of Walmart or Kragen, there must be lebenty bazillion choices of oil, some of which don't have "airplane" stamped on them. Regulations aside, and providing that I'm not dumb enough to immediately switch but to gently transition from AeroShell 100W to another type of oil, which one is the oil of choice.

Thanks for the tip on Oshkosh/SunFun. I started OSH in '73 and only missed a few years in between. I've heard the oil folks talk, but if you think for one blinkin' minute that they would do anything but chant the party line "airplane can only use our expensive aviation oil" I've got this bridge in Brooklyn I'd like to sell you.

Let's try it again with different options. No, if I had another opinion I'd probably lean towards it. This is the first shot out of the box.

Thanks,

Jim
 
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weirdjim said:
I must have been too subtle. If I go into the aviation oil section of Walmart or Kragen, there must be lebenty bazillion choices of oil, some of which don't have "airplane" stamped on them. Regulations aside, and providing that I'm not dumb enough to immediately switch but to gently transition from AeroShell 100W to another type of oil, which one is the oil of choice.

Thanks for the tip on Oshkosh/SunFun. I started OSH in '73 and only missed a few years in between. I've heard the oil folks talk, but if you think for one blinkin' minute that they would do anything but chant the party line "airplane can only use our expensive aviation oil" I've got this bridge in Brooklyn I'd like to sell you.

Let's try it again with different options. No, if I had another opinion I'd probably lean towards it. This is the first shot out of the box.

Thanks,

Jim
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I just spent $2/qt less on aviation oil than I do on oil for my car
 
I use Exxon Elite 20W-50 in my Lyc O-360-A4K. Saves me having to change oil short of 50 hours when the seasons change or I go north-south, and it provides the extra corrosion protection I want when I leave the plane to sit for more than a week. I could get much the same by adding CamGuard to Aeroshell 15W-50 or Phillips X/C 20W-50, but that's a bother I choose to do without.
 
weirdjim said:
I must have been too subtle. If I go into the aviation oil section of Walmart or Kragen, there must be lebenty bazillion choices of oil, some of which don't have "airplane" stamped on them. Regulations aside, and providing that I'm not dumb enough to immediately switch but to gently transition from AeroShell 100W to another type of oil, which one is the oil of choice.

Jim
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The one with "aviation" stamped on it. Really. There are a ton of significant differences between both the engine designs and the conditions in which they operate between the engine in your plane and the engine in your car. Putting automotive oil in a regular (i.e., Lycoming or Continental, rather than Rotax which need a different oil entirely) is an invitation to mechanical disaster.
 
if you're running exclusively unleaded fuel then you might be able to make do with a non-aviation oil
 
I went with the Phillips 20w-50 and camguard this time by. I figgured I would go with a good base oil and get the good additives from the camguard
 
weirdjim said:
I must have been too subtle. If I go into the aviation oil section of Walmart or Kragen, there must be lebenty bazillion choices of oil, some of which don't have "airplane" stamped on them. Regulations aside, and providing that I'm not dumb enough to immediately switch but to gently transition from AeroShell 100W to another type of oil, which one is the oil of choice.

Thanks for the tip on Oshkosh/SunFun. I started OSH in '73 and only missed a few years in between. I've heard the oil folks talk, but if you think for one blinkin' minute that they would do anything but chant the party line "airplane can only use our expensive aviation oil" I've got this bridge in Brooklyn I'd like to sell you.

Let's try it again with different options. No, if I had another opinion I'd probably lean towards it. This is the first shot out of the box.

Thanks,

Jim
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A very old A&P who is now deceased told me that automotive motor oils tend to have lower flash points than aviation oils. Consider the CHT your motor runs at then research the flash point of the oil you consider using. A lower flash point will lead to oil vaporization. Here is a chart with some:
http://micapeak.com/info/oiled.html

I use Valvoline VR1 50w except in the dead of winter when I may change to Valvoline VR1 20w-50. I have a O-320A with 10:1 pistons. My engine really does not like Phillips 20w-50; it just spits it out the breather. It did better with Aeroshell 15w-50 but seemed like it would break down viscosity after about 10 hours or so. I have been running the VR1 oil for about 400-500 hours or so without trouble.
 
weirdjim said:
Money isn't the point. Making the engine perform better (or at least as good as 1930s technology will allow) is the game.
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One good thing about certified aircraft is it keeps up a demand for products that would normally be phased out or replaced with something "better". Thanks to tying it to specifications, we get to keep what works, greenies be damned. For example, say what you want about 100LL, it beats the "improved", green sliming, aerated, corn enhanced, unstable swill that we put in our cars.

Sometime in the 90's, the oil companies started to lower zinc levels to reduce emissions. Problem was, zinc is an anti-wear additive. It protects flat tappets. Not really a problem considering most new engines were sporting roller tappets. Well, it was a problem for hot rod owners or anyone with an old vehicle. I remember seeing a chart once that showed cam failures rising with the reduction of zinc. The simple solution was to run a diesel oil. Now, even the staple of the hot rod and motorcycle crowd, Rotella, has reduced zinc. Do we really want an oil that would make our cams wear faster?

Next we have the air cooled thing. More thermal expansion requires looser tolerances which needs a thicker oil. The exact opposite of where automobile engine technology is going. Thinner oils with tight tolerances reduce emissions and increase fuel economy. A fancy new 0W-10 oil may be able to keep the bearings from scuffing, but not if the engine can't build oil pressure.

There are specialty oils like synthetic Amsoil Z-ROD 20W-50 that sound good at $10 a qt. It's got high zinc and corrosion inhibitors, just what we want. It's also got a fire point lower than the maximum allowable head temperature on a Lycoming and is still designed for unleaded fuel. And although Amsoil touts repairing any engine failure due to their oils, I think they would have a problem paying >$20k plus associated damages when they don't specifically say it's for aircraft use. They got rid of their aviation blend, AVOIL, long ago for liability reasons.

People that are critical of old technology and like "new and improved", need to lookup Mobil AV-1. A good example of people that know more than us, making a major improvement to something tried and true and having it go completely sideways.

I'll stick to Aeroshell.
 
Running a non aviation oil in a Lycosaurus engine with leaded gas is asking for a new engine - sooner than you think.
This is not parroting the party line - it is reality.

Personally I am partial to 15W50.
 
Running W100 Plus + CamGuard in the 1300 SNEW O-360-A4M
Reviewing the books, Phillips Type M 20W-50 was used for the break-in, then Castrol A100 until 870 hours and Aeroshell W100 Plus since. I started adding CamGuard a year or so ago due to somewhat irregular schedule and plane sitting for 2 weeks sometimes.

Anyone familiar with that Castrol aviation line? They don't seem to be as active anymore
 
I'll start this with saying that I'm not an oil engineer, just an engine engineer and go from there.

The reality is that oil is not oil is not oil. Different applications have different requirements for oil, and this should be taken into consideration with your choice of oils. Let's take a standard Japanese motorcycle with a wet clutch (same oil sump for clutch and engine): if one puts in a standard oil these days which has friction modifiers in it, one will find that the clutch will disintegrate pretty quickly.

Aircraft engines are hard on oil. They run at high power settings (lots of heat), are air-cooled (lots of heat and more combustion biproducts), and have lead in the fuel. All of this tends to lend itself to relatively short oil change intervals and I really don't think you're going to see much of a change there. These engines will still have hot spots that will heat the oil and cause it to break down over the oil change interval.

If you got rid of lead, you might be able to do something better with your oil. But until then, I think CamGuard is a logical additive to put in. The big thing that will make a difference is adding filters instead of the archaic screens. Those are cheap to do. I'd go for that.
 
and by the same token, if you're running a VW or corvair conversion in your homebuilt and you're using 100LL, then use phillips or exxon multi-grade aviation oil, not automotive oil. You're not burning auto fuel so it's no longer an auto engine.
 
Don't confuse Jeff with that logic, he doesn't know anything about diesels.

Dean V said:
So if I run jet fuel and turbine oil in a cummins its an aicraft engine?
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wabower said:
Don't confuse Jeff with that logic, he doesn't know anything about diesels.
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Beyond that jet fuel and diesel fuel likely have more in common than the swill in my car and the 100ll in my plane
 
JHW said:
and by the same token, if you're running a VW or corvair conversion in your homebuilt and you're using 100LL, then use phillips or exxon multi-grade aviation oil, not automotive oil. You're not burning auto fuel so it's no longer an auto engine.
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You'd last about a week in my Logic class.

Jim
 
weirdjim said:
You'd last about a week in my Logic class.

Jim
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If you mean that leaded fuel is illogical then I agree with you. But since lead is an unfortunate reality you'd better use an oil that can tolerate the byproducts of such.
 
Skylane81E said:
The AD keeps the junk in the oil not only so that it can be drained but so it doesn't just settle to the bottom of the pan. Besides, if it isn't in the oil how can the filter remove it?
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The spin-on filter gets the chunks that the old screen let go by. Spin-ons are typically 5 or 10-micron filters, while that screen is a many-micron filter, probably 50 to 100 or worse. And there's a lot of area in a spin-on filter, too, to accumulate all that fine trash that otherwise just ends up settling in low-flow places like hydraulic lifters and making them stick.

Aircraft spin-ons are a much heavier unit than a Wal-Mart Fram filter. Lycomings can run their oil pressure up to 100 PSI; not many cars do that, unless the newer ones that I've never fooled with do. 40 psi would be more normal for such a filter.

A friend sells oil supplements for heavy machinery and so on. He has cut apart a variety of commonly-available auto filters, and the quality varies wildly. Some of them had holes in their thin media large enough to see through. An aircraft filter has a thick media and more pleats to increase the filtration area. It costs more because it costs more to make, it's not made in China, and there are huge liability issues associated with it.

Some homebuilders and maybe some spam-can owners, too, used to use the Frantz filter. It's not a certified system, but is sure got the oil clean. It was a bypass filter, which was mounted in some convenient place and a couple of hoses fed and drained it. Oil was tapped off the oil pressure port, run through a restrictor and the filter, and dumped back into the sump. The media was a roll of toilet paper, and the oil was run lengthwise through the roll. It came out nearly as clean as it came out of the bottle, but being a bypass filter it didn't clean the oil immediately before the engine got t. I had one on a Chev truck and the oil was never anywhere near dark. Problem now is that most retail toilet paper is too loose and cheap and the core too large. Institutional stuff is necessary.

http://www.frantzoil.com/home.html

Dan
 
weirdjim said:
Citation??

Jim
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Nah, that has turbines, completely different issues.

:)





(Disclaimer for the humor impaired: Yeah, I know what he meant, just being obtuse to add a little levity.)
 
Dan Thomas said:
The spin-on filter gets the chunks that the old screen let go by. Spin-ons are typically 5 or 10-micron filters, while that screen is a many-micron filter, probably 50 to 100 or worse. And there's a lot of area in a spin-on filter, too, to accumulate all that fine trash that otherwise just ends up settling in low-flow places like hydraulic lifters and making them stick.

Aircraft spin-ons are a much heavier unit than a Wal-Mart Fram filter. Lycomings can run their oil pressure up to 100 PSI; not many cars do that, unless the newer ones that I've never fooled with do. 40 psi would be more normal for such a filter.

A friend sells oil supplements for heavy machinery and so on. He has cut apart a variety of commonly-available auto filters, and the quality varies wildly. Some of them had holes in their thin media large enough to see through. An aircraft filter has a thick media and more pleats to increase the filtration area. It costs more because it costs more to make, it's not made in China, and there are huge liability issues associated with it.

Some homebuilders and maybe some spam-can owners, too, used to use the Frantz filter. It's not a certified system, but is sure got the oil clean. It was a bypass filter, which was mounted in some convenient place and a couple of hoses fed and drained it. Oil was tapped off the oil pressure port, run through a restrictor and the filter, and dumped back into the sump. The media was a roll of toilet paper, and the oil was run lengthwise through the roll. It came out nearly as clean as it came out of the bottle, but being a bypass filter it didn't clean the oil immediately before the engine got t. I had one on a Chev truck and the oil was never anywhere near dark. Problem now is that most retail toilet paper is too loose and cheap and the core too large. Institutional stuff is necessary.

http://www.frantzoil.com/home.html

Dan
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Yep, I've cut open an aircraft next to an auto filter and the difference is startling.
 
JHW said:
If you mean that leaded fuel is illogical then I agree with you. But since lead is an unfortunate reality you'd better use an oil that can tolerate the byproducts of such.
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Some automotive oils do as well with leaded fuel as aviation oil (basically anything that's mineral based). AFaIK the real issue with automotive (with detergent additives instead of dispersants) is the former's tendency to produce metal ash deposits in the cylinders which become secondary ignition sources when things get hot. And at high power said ignition sources can destroy an engine in minutes. IOW, it's the high temps and continuous high power that requires AD oils, not the lead.
 
Lance, if you get a secondary ignition source you likely won't have minutes before dynamic engine disassembly, preignition can kill an engine nearly instantly.
 
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