W80 vs W100

[herethere22]

Can someone tell me the recommended operating temperatures for these oils? Thanks.

[Hedley]

This time of year, don't use either. Go multigrade -
Aeroshell 15w50 (black bottle) is best, Philips 20w50
(blue bottle) if you're a cheap bastard.

[iflyforpie]

We use W80 as the temperature gets below freezing and throughout the winter as each oil change comes up.

For private aircraft I recommend 15W50 as it makes it easier to start in cold weather and will not need to be changed for the summer if you don't fly that many hours (however I find it breaks down at high temperatures, resulting in low oil pressures). Also for high cam Lycomings affected by AD80-04-03R2, 15W50 includes the additive required which offsets the higher cost compared to straight grades.

We used to run 20W50 at my former company and never had any problems with it.

[herethere22]

Thanks for your respsonses Hedley and Flyforpie. I did some further research myself from the Shell Aviation website and it has W80 at (-17 to 21C) and W100 (15 to 30C). Just wondering Hedley why you suggest not using W80 at this time of year then? The 15W50 is advertised as the ultimate oil so why would I then use anything else? The aircraft is a C152 and I fly it way more in the spring-summer-fall months. I'm a fair weather player you could say. Should I just switch to 15W50 year round then? Thanks.

[iflyforpie]

I would recommend in your case 15W50 year round (and I do to all of my private customer). It will start easier in colder temperatures but the viscosity is thick enough for the summer.

On our 172, the 15W50 breaks down at OATs higher than 30C but it might be different for your engine/situation. Here we run straight grades because we fly more hours, it is cheaper, and our planes are hangared and preheated.

I would also recommend inhibiting your engine during the winter if you don't plan on flying it or at least changing the oil twice a year to help remove moisture from your engine if you fly less than 50 hours. The alternative is to run your engine up to operating temperatures at least once per month.

[mag check]

Personally, I would(and do) stay away from the 15w50. Being a semi-synthetic, it doesn't seem to stick onto the internals of the engine for as long, so if you don't fly very often, in my experiance, you will end up with corrosion/wear issues.
I run 80 in the winter, 100 in the summer, unless it is a small continental, cause the 100 isn't approved.
It's too bad that w65 isn't available anymore.

[Strega]

Personally, I would(and do) stay away from the 15w50. Being a semi-synthetic, it doesn't seem to stick onto the internals of the engine for as long, so if you don't fly very often, in my experiance, you will end up with corrosion/wear issues.
I run 80 in the winter, 100 in the summer, unless it is a small continental, cause the 100 isn't approved.
It's too bad that w65 isn't available anymore.

Can you support this somehow?

[Troubleshot]

Personally, I would(and do) stay away from the 15w50. Being a semi-synthetic, it doesn't seem to stick onto the internals of the engine for as long, so if you don't fly very often, in my experiance, you will end up with corrosion/wear issues.
I run 80 in the winter, 100 in the summer, unless it is a small continental, cause the 100 isn't approved.
It's too bad that w65 isn't available anymore.

Can you support this somehow?

Before I "support" this information I want to know if you have ever disassembled an aircraft engine and then re-assembled it?

[ruddersup?]

I lost several cams on our Navajo engines while running on 15W50 and then I switched to 20W50 and never had a failure. Now this is not definitive proof that 15W50 is not good BUT don't ask me to put any in my engines. Oh by the way we put 30,000 hrs on these engines.

[cgzro]

Problem with the 80W is it does not have the lycoming oil additive so you have to buy and add separately.

I run 100W+ up to about October then 15W50 till temps are about 10C or so again. For Jan/Feb I'll put in preservative 2F.

I pre-heat the heck out of my engine when its below about 8C so that my oil pressure is instantaneous when I start.

Peter

[iflyforpie]

15W50 definitely is not good for turbo engines like the TIO-540s on the 'Ho and we had all kinds of problems with it on the (L)TO-360s on our Seminole.

The additive is only required for Lycomings that fall under the AD I mentioned earier. These are H series Lycoming O-320s and high cam O-360s (I believe they are called the 76 series). Don't bother putting the additive in if the engine doesn't require it or use 15W50 simply because it has the additive in it (you aren't saving any money by buying the more expensive 15W50).

If it was my personal plane I would run all straight grades, but the better cold starting of the 15W50 would probably be better for the private planes that spend most of the cold months sitting (even W80 can be like glue).

I've never noticed 15W50 not sticking to the innards of a engine as well but it is easy enough to tell during a jug change (I always look at the cam, especially on Lycs).


I wonder why they haven't come out with W80+ yet?

[Troubleshot]

AHHH !! you guys are supposed to let "The Master" answer the question.

[Strega]

I want to know if you have ever disassembled an aircraft engine and then re-assembled it?

Yes,,

And they ALL have made TBO and beyond.......

Why dont you use straight weight oil in your car? (IE WRX Subaru)

Why does the trucking industry not use straight mineral grades of oil? and dont give me some BS as to "the fuel has lead in it"


I don't care what the "Back Yard" mechanics on this forum say, Aeroshell 15W50 and Exxon Elite 20W50 semi-synthetic oils are some of the best there are.. Do you think you are smarter than the Engineers (of the P. type) at these companies?

[Strega]

So Can you support your claim that the W80 "sticks' better?

I didnt see "sticks" on the spec sheet from Shell, so maybe you could enlighten us as to what "Sticks" means quantitatively.

[Bullet Remington]

I want to know if you have ever disassembled an aircraft engine and then re-assembled it?

Yes,,

And they ALL have made TBO and beyond.......





Ah the resident Jack of all Trades and Master of None has poked his self serving nose into this!! I'd love to see those engines Stegra! Are those the one's you designed and built yourself from metal salvaged from the trash bins behind your mother's house, and melted down yourself???


I don't care what the "Back Yard" mechanics on this forum say, Aeroshell 15W50 and Exxon Elite 20W50 semi-synthetic oils are some of the best there are.. Do you think you are smarter than the Engineers (of the P. type) at these companies?

Unfortunately, I agree with you, Multi grades listed are much better then the straight 80 and 100's referenced on this thread. I'd expound on that a bit, but it would take you awhile of surfing to try and find something that you could use to refute my comments.

As for your back yard mechanic comment, most back yard mechanics are better then "arm chair mechanics/ wanna be engineers" ( of the P Type), than those that lurk/ troll in the back ground until they find something they can use to belittle other folks, while attempting to inflate their own ego!!

As for your question on being smarter then the engineers (of the P Type) at these companies, I don't know! Can't say I've ever had the opportunity to discuss anything substantitve with them. Having said that, I do know for a fact, that the majority of folks who post here are much, much smarter then you give them credit for. And that by default makes them smarter then you are!

[Hedley]

I like the 15w50 because it flows SO much easier during
cold starts. If bare, dry metal-on-metal doesn't bother
you, sure, run a straight grade oil during winter.

Sure, you can run a thin straight grade in winter, to try to
get some better flow during the first minute of operation,
but if it does, then it's probably going to be too thin and
break down under pressure.

During the winter, I run 15w50 (to avoid metal-on-metal
during cold starts) and 100Wplus during the summer.

100Wplus is a GREAT oil - in warm temps. It has LW16072
and withstands the high temps of summer MUCH better
than 15w50. The problem with the magical multi-viscosity
oil is that it is a sae 15w base stock oil which has had very
expensive Viscosity Improvers (VI's) added to it, to give
it that coveted sae 50w viscosity at temperature. The problem
is that VI's break down under high heat, so during the
summer, if you go too long between oil changes with
15w50, you end up with a very thin 15w oil, which ain't
good.

100wplus costs MUCH less than 15w50, and doesn't
have the VI's to break down at high temps, and it has
the LW16072, so I'm not sure why people don't run
100wplus in the summer. Costs less, works better.

Now, if you're going to store an engine for a long
period of time (say longer than 2 weeks) then the
15w50 will run off the engine faster than the 100wplus,
because at room temp, it's viscosity is sae 15w as
opposed to sae 50w.

But if you're going to store an engine, best to run some
Shell 2F in it, which is a proper, corrosion-inhibiting pickling
oil. It's really not very expensive.

Not sure why people argue so much about pretty cut-and-dry
subjects like this. Also not sure why the personal insults are
required for a discussion of such an obscure topic.

[Strega]

MR Bullet,

I was not the one here bewittling anyone..

read back through the posts.....

[mag check]

I like the 15w50 because it flows SO much easier during
cold starts. If bare, dry metal-on-metal doesn't bother
you, sure, run a straight grade oil during winter.

Sure, you can run a thin straight grade in winter, to try to
get some better flow during the first minute of operation,
but if it does, then it's probably going to be too thin and
break down under pressure.

During the winter, I run 15w50 (to avoid metal-on-metal
during cold starts) and 100Wplus during the summer.

100Wplus is a GREAT oil - in warm temps. It has LW16072
and withstands the high temps of summer MUCH better
than 15w50. The problem with the magical multi-viscosity
oil is that it is a sae 15w base stock oil which has had very
expensive Viscosity Improvers (VI's) added to it, to give
it that coveted sae 50w viscosity at temperature. The problem
is that VI's break down under high heat, so during the
summer, if you go too long between oil changes with
15w50, you end up with a very thin 15w oil, which ain't
good.

100wplus costs MUCH less than 15w50, and doesn't
have the VI's to break down at high temps, and it has
the LW16072, so I'm not sure why people don't run
100wplus in the summer. Costs less, works better.

Now, if you're going to store an engine for a long
period of time (say longer than 2 weeks) then the
15w50 will run off the engine faster than the 100wplus,
because at room temp, it's viscosity is sae 15w as
opposed to sae 50w.

But if you're going to store an engine, best to run some
Shell 2F in it, which is a proper, corrosion-inhibiting pickling
oil. It's really not very expensive.

Not sure why people argue so much about pretty cut-and-dry
subjects like this. Also not sure why the personal insults are
required for a discussion of such an obscure topic.

Hedley, while i agree with most of what you say here, I do have a bit of a problem with some of your points.
All engines that have sat for more than a short time since last run will have metal to metal contact. The only question is how long that contact continues.
The only way to not have this start up wear is to use a pre oiler.

Start up oil pressure should not be a problem no matter what oil is being used because the engine would be preheated before trying to start it. Even W100 at -30 will be thin enough to start once it is preheated up to 140*F

[Hedley]

pre oiler

I love pre-oilers!

Even W100 at -30 will be thin enough to start once it is preheated up to 140*F

Couple of problems there

(1) if you think every aircraft engine in Canada is thoroughly
pre-heated to 140F before every start in winter, um ...

(2) even if you did pre-heat to 140F, you would still have
a problem with the w100 congealing in your oil cooler
at an OAT of -30C! According to Shell's MSDS sheets,
100 has a pour point of -23C, while 15w50 has a pour
point of -36C.

Weird how people here don't know about pour point
and oil congealing in oil coolers. Lots of airplanes have
been lost because of this in the past. Lots of personnel
turnover recently, too, I guess. Too bad we have to
re-learn lessons of the past again.

Straight grade is a poor, obsolete choice for winter
ops. Go with the multi-grade for winter.

[iflyforpie]

And I thought my oil cooler was non-congealing!

Hedley does have a point about the oil congealing in congealing oil coolers and the fact you can't preheat them other than poorly with a space heater and engine blanket. But for me it doesn't get to -30 OAT even outside the hangar.

[herethere22]

I didn't realize this was such a hot topic when I posted it. Based on what I've gathered here and from elsewhere I plan to run mulitgrade 15W50 in the winter and was already running 100plus for summertime (15+C) and will continue to do so. Thanks to all for their information. PS who is the "Master"?

[Hedley]

who is the "Master"?

A switch on the panel AFAIK

[mag check]

pre oiler

I love pre-oilers!

Even W100 at -30 will be thin enough to start once it is preheated up to 140*F

Couple of problems there

(1) if you think every aircraft engine in Canada is thoroughly
pre-heated to 140F before every start in winter, um ...

(2) even if you did pre-heat to 140F, you would still have
a problem with the w100 congealing in your oil cooler
at an OAT of -30C! According to Shell's MSDS sheets,
100 has a pour point of -23C, while 15w50 has a pour
point of -36C.

Weird how people here don't know about pour point
and oil congealing in oil coolers. Lots of airplanes have
been lost because of this in the past. Lots of personnel
turnover recently, too, I guess. Too bad we have to
re-learn lessons of the past again.

Straight grade is a poor, obsolete choice for winter
ops. Go with the multi-grade for winter.

Hedley,
I'm quite familiar with congealing oil coolers, and I agree that it can be a serious problem with a pilot that dosen't recognize the symptoms, and I've had the "pleasure" of working with some pilots that didn't.
That said, with the proper cold weather kit on the aircraft, it "should" never be a problem, as the cooler will be flowing.

As far as preheating goes, I sure hope that everyone is doing it.
I guess I'm spoiled, but everything gets kept inside every night here

[Bullet Remington]

I want to know if you have ever disassembled an aircraft engine and then re-assembled it?

I don't care what the "Back Yard" mechanics on this forum say, Aeroshell 15W50 and Exxon Elite 20W50 semi-synthetic oils are some of the best there are.. Do you think you are smarter than the Engineers (of the P. type) at these companies?

Read back through as you suggested, Stegra.

Here's the latest of your " cheap and enfantile" shots. I could have listed anoter 16 of these, but I don't have the time! Further, I seriously doubt if you can actually accept that you have insulted 90% of the " engineers ' on this forum. (and yes, there are several " P. Engineers" on here that find you obsessive mannerisms and objections to any AME that uses the term " engineer", (in their words) bordering on psychotic)

Did you insult any body? I certainly believe so. I'm, in your words, " on here" and I'm being included in the " back yard mechanic" group by default.

I take that as an insult. And I respond in kind.

[ruddersup?]

Re: Aeroshell 15W50

Strega, if one were to use this oil and had premature cam failure (engine, not me) and called Shell to discuss the problem and they would not even call me back what might be your next move?

At over $15,000 for a repair I gave the oil another try. A few months later, same thing different plane.
I contacted another carrier (with mega Navajo experience) for his advice and he said he ran into the same problem with his Navajos. He switched to Phillips 20W50 a few years earlier and never lost a cam since.

You have an explanation for this?

Strega, you use Slick 50 in your car? Smart engineers there too.

Strega, how many Navajo engines have you had go to TBO using 15W50? I wonder how many engines you've had go TBO? Oh, I know, all of them, we just change the cam at mid time.