Areoshell 100 for winter?

I used to run W100 year round. Then I went missed on approach to my home field and had to divert to a nearby field. The plane was left outside with no heat in a TN winter. When I started it turned over slightly slower than normal, though it always tends to turn over the first revolution a little slow I guess due to my 10:1. The kicker though is when I sat there watching, waiting, for the oil pressure gauge to read something, anything...it took a long time. It was long enough that I considered shutting it down. From then on I switched to 20W50 in the winter.
 
If it's below 40 degrees and your starting with unpreheated 50w oil your doing damage. As forane described the oil actually cavatates at the oil pump as its to thick to get sucked in. Not good for oil pump either.

Also the other reason for preheating is to keep from scuffing the cylinder walls as the steel and there is a slight taper/choke so the barrel actually gets smaller towards the cylinder head. This is because of the huge temperature differential between the base (190f) and the head (400f). So when everything is up to temp, it's all the same size.

The Pistons are aluminum and expand faster than steel. If it's 0f degrees and you cold start the engine without preheating, no oil is going to help you as the piston is gonna make contact with the cylinder in the tighter choke areas.

The relation of starting cranking speed should not be used as a indication of when to switch to a lighter weight oil or when to preheat.

Here is a another great write up from Mike Busch on the subject:

http://www.avweb.com/news/maint/182846-1.html
 
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If it's below 40 degrees and your starting with unpreheated 50w oil your doing damage. As forane described the oil actually cavatates at the oil pump as its to thick to get sucked in. Not good for oil pump either.

Also the other reason for preheating is to keep from scuffing the cylinder walls as the steel and there is a slight taper/choke so the barrel actually gets smaller towards the cylinder head. This is because of the huge temperature differential between the base (190f) and the head (400f). So when everything is up to temp, it's all the same size.

The Pistons are aluminum and expand faster than steel. If it's 0f degrees and you cold start the engine without preheating, no oil is going to help you as the piston is gonna make contact with the cylinder in the tighter choke areas.

The relation of starting cranking speed should not be used as a indication of when to switch to a lighter weight oil or when to preheat.

Here is a another great write up from Mike Busch on the subject:

http://www.avweb.com/news/maint/182846-1.html
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There is a couple of things incorrect in your post...

1- Not all cylinders are ( choke bore)....

2- Regardless of the choke bore or straight bore cylinders, there is ALWAYS piston to wall clearance built in..... You would have to get the motor started and instantly go full throttle, and keep it there for several minutes to get the pistons to grow faster then the bore size and have contact/ scuffing...

If any pilot is dumb enough to do that stupid trick.. they deserve to ruin their motor...:rolleyes: IMHO..
 
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There is a couple of things incorrect in your post...

1- Not all cylinders are ( choke bore)....

2- Regardless of the choke bore or straight bore cylinders, there is ALWAYS piston to wall clearance built in..... You would have to get the motor started and instantly go full throttle, and keep it there for several minutes to get the pistons to grow faster then the bore size and have contact/ scuffing...

If any pilot is dumb enough to do that stupid trick.. they deserve to ruin their motor...:rolleyes: IMHO..




1. My 200hp io-360 has choke cylinders....and in reading it sounds like most cylinders modern airplane engines do.

2. Mike Busch displayed numerous pictures showing evidence of piston to choke/taper clearance contact. Obviously there is no way of telling if they went to full power after cold start but using some common sense would tell me that most pilots don't hold the throttle wide open after starting.

How many planes have you seen on the ramp at full throttle after start? Sure a few where the operator bright the rpms up higher than needed, but not full power.

I think I've contributed all I can to this thread give the direction the audience seems to be going...
 
"And, once the engine is started, it couldn't give a **** about what the ambient temperature is."

I've had my oil temp drop below the bottom of the recommended operating range when descending from mid teen altitudes on a cold day.
 
If it's below 40 degrees and your starting with unpreheated 50w oil your doing damage. As forane described the oil actually cavatates at the oil pump as its to thick to get sucked in. Not good for oil pump either.

Also the other reason for preheating is to keep from scuffing the cylinder walls as the steel and there is a slight taper/choke so the barrel actually gets smaller towards the cylinder head. This is because of the huge temperature differential between the base (190f) and the head (400f). So when everything is up to temp, it's all the same size.

The Pistons are aluminum and expand faster than steel. If it's 0f degrees and you cold start the engine without preheating, no oil is going to help you as the piston is gonna make contact with the cylinder in the tighter choke areas.

The relation of starting cranking speed should not be used as a indication of when to switch to a lighter weight oil or when to preheat.

Here is a another great write up from Mike Busch on the subject:

http://www.avweb.com/news/maint/182846-1.html


The expansion rate difference is not an issue, if it was you'd have heads burning off cylinders as combustion gasses leaked by after starting.
 
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There is a couple of things incorrect in your post...

1- Not all cylinders are ( choke bore)....

2- Regardless of the choke bore or straight bore cylinders, there is ALWAYS piston to wall clearance built in..... You would have to get the motor started and instantly go full throttle, and keep it there for several minutes to get the pistons to grow faster then the bore size and have contact/ scuffing...

If any pilot is dumb enough to do that stupid trick.. they deserve to ruin their motor...:rolleyes: IMHO..

The fallacy in that theory is, the difference in thermal expansion rates of the aluminum piston, and the steel cylinder.
 
The fallacy in that theory is, the difference in thermal expansion rates of the aluminum piston, and the steel cylinder.


The expansion rate of the piston and the cylinder is closer then you think... It takes a VERY high power setting from first second of start to get the piston to "grow" into the cylinder wall.. And even then, it is a very rare occasion.. IMHO...

Ps...Good to have you back for some lively debates...:thumbsup:
 
Well....duh...but the heavier the weight, non-synthetic oils stay on days longer.

In fact on a io-360 after shut down it take 2 days for 1/4 quart to come back to sump and up to 7days for the 3/4 of a quart to return to the sump.

I've ran 15-50w semi-syn oil and after about 2 days it's all back in the sump.

Just pull the dipstick on 50w vs 15-50w and it clings to it much better.

All that oil-- 3/4 of a quart--isn't dripping off exposed stuff like cams and lifters. It's seeping out of the filter and galleries. When the engine is shut down, it's HOT and the oil is thin, even W100, and runs off exposed bits quickly. Besides freezing the oil for my students to see what it did at low temps, I submerged quarts of it in a pan of boiling water so they could see what happened to the viscosity at over 200°F. The single grade oils changed the most. Got pretty runny, almost as runny as 15W50.

Lycoming started building engines (and converting older one during factory overhauls) to roller lifters about ten years ago, just to get around the scuffing that happens during start.

Dan
 
Funny thing, I've been reading a new book I just got, it mentioned seaplane operators removing their batteries and taking them in for the night, as well as their oil.

A good freezing winter precaution is drilling some small holes in the top sides of your crank case breather tube incase it freezes up.

You also have the pour point of your oil. You'll ether know it, or see it when your oil congeals in your cooler and pressure spikes.

100W -4F

15/50 -43F

This is far colder then most here will fly in, but.. Even with a good preheat, split weight is a good call for winter.

The 15/50 is going to run through the engine easier, getting to all the parts needing lubrication better.
 
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You also have the pour point of your oil. You'll ether know it, or see it when your oil congeals in your cooler and pressure spikes.

Thick oils have been known to destroy oil coolers when cold. The typical setup has the oil cooler plumbed with a bypass controlled by a Vernatherm, which just opens a channel in the engine so that the oil doesn't pass through the cooler until it warms up some, but the cooler is still part of the pressure system and gets too much pressure when the oil is so thick that the relief valve can't dump it fast enough. A good oil cooler check is to shine a light through the airflow channnels and see that the oil passages haven't swelled.


Dan
 
Ummm....no, they're not. Try again?

Show me a article that was written by some who does not have a axe to grind. Every oil company and additive maker will say their product is the best and have a dozen studies to prove it.

But one must realize who is the CFI and who is the A&P-IA building and servicing aircraft.

If you really want to know how much any oil or additive protects against corrosion try this, buy some steel strap 1/2" wide X 12" long grind one side clean, dip half of the clean side in your favorite oil, hang it outside see how well it really protects against the elements.

See how long it takes to drip off.
See if it leaves any thing to protect the steel.
 
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Funny thing, I've been reading a new book I just got, it mentioned seaplane operators removing their batteries and taking them in for the night, as well as their oil.

We have been doing that in the colder regions for over 100 years. That was the only way the early Alaskan pilots could operate in the winter.

A good freezing winter precaution is drilling some small holes in the top sides of your crank case breather tube incase it freezes up.

That is an AD for lycoming engines, not just a good idea.

You also have the pour point of your oil. You'll ether know it, or see it when your oil congeals in your cooler and pressure spikes.

100W -4F

15/50 -43F

This is far colder then most here will fly in, but.. Even with a good preheat, split weight is a good call for winter.

The 15/50 is going to run through the engine easier, getting to all the parts needing lubrication better.

15 weight oil always pours easier, but it requires additive packages to fortify it to meet aviation engine requirements due to the clearances in the engine bearings.
 
All that oil-- 3/4 of a quart--isn't dripping off exposed stuff like cams and lifters. It's seeping out of the filter and galleries. When the engine is shut down, it's HOT and the oil is thin, even W100, and runs off exposed bits quickly. Besides freezing the oil for my students to see what it did at low temps, I submerged quarts of it in a pan of boiling water so they could see what happened to the viscosity at over 200°F. The single grade oils changed the most. Got pretty runny, almost as runny as 15W50.

Lycoming started building engines (and converting older one during factory overhauls) to roller lifters about ten years ago, just to get around the scuffing that happens during start.

Dan



I just uploaded a pic of my cam after sitting for 2 weeks with a big drop of straight 50w oil still clinging on the cam lobe....

Oil drains back from everywhere over time, but one thing is clear that heavier weight oil protect better against corrosion by staying on the parts longer.
 
Show me a article that was written by some who does not have a axe to grind. Every oil company and additive maker will say their product is the best and have a dozen studies to prove it.
To my knowledge, neither Lycoming nor TCM make lubricating oil.

But one must realize who is the CFI and who is the A&P-IA building and servicing aircraft.
...and who are the real experts on the engines and the best choices for lubricating them -- the folks who built them.
 
If you really want to know how much any oil or additive protects against corrosion try this, buy some steel strap 1/2" wide X 12" long grind one side clean, dip half of the clean side in your favorite oil, hang it outside see how well it really protects against the elements.

See how long it takes to drip off.
See if it leaves any thing to protect the steel.

Here's the results of that test:

http://www.avweb.com/news/maint/oil_myths_debunked_197096-1.html

and behind their paywall: http://www.aviationconsumer.com/issues/41_4/industrynews/6113-1.html

tl;dr multi-weight oil outperforms straight weight.
 
...and who are the real experts on the engines and the best choices for lubricating them -- the folks who built them.

That statement doesn't carry much weight considering how long it took the engine mfgrs to get on board with LOP operations. And, are they even on board today? (I don't know, I haven't kept track). Does LOP operation still void Lycoming warranties? (A quick google search indicates that it does)

John Deakin, who I consider a true expert says this:

CMI (nee TCM) and Lycoming ARE experts when building an engine, and telling us what the limitations are! But they are NOT expert at anything to do with FLYING those engines, because they do not fly them. They are limited to very primitive test stands with none of the sophisticated Engine Monitor Systems (EMS) owners install today. In fact, neither company has even mentioned them in official publications of which I am aware. It’s been 30 years and more!

Here's a great article of his on the topic from last year:

lycoming and continental, dumb and dumber
 
My flight school uses 15w/50 multigrade. What's wrong with it?
 
My flight school uses 15w/50 multigrade. What's wrong with it?

Even Lycoming's instructions say to not use it in any of their engine that have a friction clutch drive assemblies.

that is most of the Continental engines.
All 0-200, 0-240, 0-300-D, IO-360 have friction clutch starter drives as well as the 0-470, 0-520 & 0-550 series.
The additive package in Aeroshell 15-W-50 is a polishing agent, it will polish the friction clutch well enough that it will not spin the engine to start.

Lycoming's 0-3XX series use a bendix starter it is not an oil bath starter system.

READ
http://www.lycoming.com/Portals/0/t...Lycoming Engine PN LW-16702, Oil Additive.pdf

Aeroshell 15-W-50 has this additive. many other oils comply with this AD/instruction with different additives that do not effect friction clutches.
 
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My flight school uses 15w/50 multigrade. What's wrong with it?

For you, none, likely none for them either if they are busy. The problem with the Aeroshell 15w50 is the synthetic base stock it uses doesn't adequately deal with the by products of combustion of 100LL which can lead to metal damage issues when the engine sits around.
 
I performed the oil change today. I stuck with the w100 plus and Ill see how it goes. If needed I can always switch oils.

My buddy has a filter cutter and asked if I wanted to cut the filter. I was scared being its the first time since I owned it. I said yep lets do it. Nervous as can be, as I pulled the element out and undid the accordion paper..we found NO metal. I was happy. Now Ive got to send my oil sample off and all is good.

Was a good day of flying too!
 
That's good news! Glad your past the first filter cutting episode!

I didn't on this one but on the next I will cut the filter at prebuy I think......
 
Alaska guy here. My airplane stays outdoors year-round. I use Phillips XC 20/50 all year. Aeroshell 100 will work fine as long as you preheat the engine well. When the engine is cold the cranking speed will be slow and your battery will drain quickly trying to turn it over. Your oil pressure will be slow to develop once it starts. Nothing good. Everything about multi-vis is better in cool temps. And as far as I'm concerned in Alaska summer temps. I'll start my plane without heat down to about 20* and that's with a little Odyssey on the firewall. I couldn't do it with 100wt in the engine. And FWIW I agree with the previous poster who said to avaoid Aeroshell 15-50. Not a fan.
 
To my knowledge, neither Lycoming nor TCM make lubricating oil.

...and who are the real experts on the engines and the best choices for lubricating them -- the folks who built them.

You are absolutely correct, and neither manufacturer requires any thing but the mil spec qualities for their engines. except for the Lycoming CYA AD for their screw up on the 0-320-H2AD.

All other engines require nothing but oil that meets the mill spec.
Yes they know what is good for their equipment, They know the cheapest oil out there that meets that mil spec will do the job.

Every thing else you hear or read is nothing But advertisement hype, written to sell oil.

If you really believe aero shell is go to go with the Lycoming additive in all engines read the caution in your own link.
 
And FWIW I agree with the previous poster who said to avaoid Aeroshell 15-50. Not a fan.
I do not know a single Alaskan Pilot who will disagree with that.
 
I would like to hear from more real cold weather pilots. Tom , who always has a contrary opinion, may not know very many Alaska , or other cold weather pilots. I have used 15-50 shell for years with no problems. I think most FBOs use whatever oil they get the best deal on from the distributor. Incidentally, the porsche 2014 owners manual specifiys 0-40 Mobil one oil which is used by the local dealer.( porsche is, of course, a horizontally opposed boxer engine) porsche has built these type engines for quite a few years.
 
Porsche doesn't run highly leaded fuels.

Neither do I. ;)

I like semi synthetic 15w 50 AeroShell. Synthetic motor oil is the best you can do for your engine. Granted it does not disburse lead well, that is why it is semi synthetic. If you don't use leaded fuel you can run a full synthetic oil. Rotax engines love it. :yes:
 
Engine starts seem to be a critical event. Some of our planes fly multiple times a week and tend to stay lubed, loose and limber. Some of our planes fly only fly once or twice a month but tend to put a few hours on each time they fly and over the engine's lifetime, they don't experience an abnormally large number of cold starts.

In the middle of my last engine's lifetime, it flew several times a month but experienced 4-5 times the number of cold starts and cold shutdowns due to a peculiar situation. This went on for about 3 years. The oil analysis trends changed noticeably and soon I had cam spalling.

I came away convinced that most of us operate our engines in ways that make the selection of engine oil a non-critical factor in engine life. We don't do an excessive number of cold starts relative to the hours flown to TBO. Use a good aviation oil and run the engine within a wide range of normal operations, no problems.

But do enough more stressful cold start operations and I feel like I saw how the relative strengths and shortcomings of some engine/oil combinations may surface.

I used to run Aeroshell 100 in the warm half and Aeroshell 15-50 in winter. I did have cam spalling after 2-3 years of cold start abuse.

I now run Phillips XC 20-50 with Camguard most/all of the year. If I have a change in spring that will clearly cover the summer and get changed out before fall, I'll use Aeroshell 100.

Of course I lack sufficient data or broad operating experience to have a well informed opinion. But reading and talking as much as I can, I settled there.
 
My attitude about Aeroshell 15-50 comes from my own experiences with it. I used to use it. I used to chase phantom oil seeps and blow-by issues. I tried to run the engine hard and often to improve ring seal. I'd have the cowls off trying to find the origin of oil that distributed itself inside my pressure cowl. One day I had a starter clutch start to slip. I didn't know the urban legend about oil and starter clutches (yet) so I asked an expert I happened to have access to at the time. Some of you may recognize the name Ben Visser, who at that time was the face and voice of Aeroshell engineers. We had a short chat after an event and during the chat he advised me to try a different engine oil to see if my issues changed. Low and behold my leaks stopped. Not slowed down but stopped. My blow-by issues stopped. Not only did the breather drool disappear but the discoloration of my fresh oil change didn't happen as it usually had. The starter clutch never slipped again. Not once. Ben had told me that if an engine had any tendencies toward leaking or using oil those tendencies would be exaggerated by 15-50. And he was spot on. I've seen and heard of lots of guys be disillusioned by breather drool. That drives every pilot nuts. If it happens to you with 15-50? Do yourself a favor. Switch to Phillips XC 20-50 for an oil change or two and watch what happens. Note that the honey colored oil you added stays honey colored instead of quickly turning from honey to gray to black. Watch your compression readings improve. Watch those pesky oil seeps at the prop shaft or case seams slow or stop. All by using fully approved, multi-vis, ashes dispersant mineral oil instead of semi-synthetic. Frankly, I believe lots of guys spend lots of maintenance dollars dealing with problems that are really just symptoms of using the wrong oil. I know I did.

FWIW, I add Camguard to my engine oil. At around $20 per pint it's expensive stuff. Funny thing, I can save enough using Phillips at an oil change to add Camguard and end up at the same cost as if I'd used Aeroshell 15-50 alone. And I have better oil and a very good corrosion package. If you aren't familiar, here's a link for Camguard. http://www.aslcamguard.com/products/aviation You can see their test reports for corrosion and wear. In the graphs 15-50 SS is semi-syn Aeroshell, 20-50 SS is semi-syn Exxon Elite, 100 is Aeroshell, and 20-50 is Phillips X/C. Aeroshell 15-50 with Camguard edges out all others in the humidity tests but the margin isn't enough to be concerned with. The improvement that Camguard makes to all oils is pretty impressive, though. What really interests me is the wear test data (in the tech data tab). Phillips X/C with Camguard or Aeroshell 100 with Camguard clearly beat the semi-synthetics. All else being equal that would be enough to lead me to use 100% mineral oils rather than semi-synthetics. Add the price difference and performance advantages in my own airplanes and Phillips gets my confidence. Most of the guys I know use Phillips for the same reasons I do. We prefer multi-viscosity engine oil for it's clear cool weather advantages and Phillips because it does a better job. It isn't about prestige or brand loyalty, it's about what works.

One more comment supporting X/C 20-50. ECI, who I trust for engine parts and tech, recommends using X/C 20-50 for an engine's life including at break-in. I used it to break in my last new motor (Cub) and it worked perfectly. On my TCM 520 I've had a couple of E valve issues that required cylinder service. I returned those cylinders to service using X/C 20-50 and they broke in perfectly.

My opinions based on my own experiences. Nothing more. Cheers.
 
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I won't argue a guy's choice of oil but I will ask one question. Do you think it's the best product you can choose or is it just good enough? Have you tried other oils to see if one works better? (refer to post #75 on the previous page) Okay, two questions. :wink2:

Happy Thanksgiving.
 
I won't argue a guy's choice of oil but I will ask one question. Do you think it's the best product you can choose or is it just good enough? Have you tried other oils to see if one works better? (refer to post #75 on the previous page) Okay, two questions. :wink2:.
A really great question but how to know?

Trying other oils is not really a solution for the owner of a personal plane. How would you know if one is better than the other? Oil analysis is a great thing but it won't tell you whether 1 is better than another.

It seems to me that all you can do is research the topic, figure out who you believe and go with their recommendations.
 
I would like to hear from more real cold weather pilots. Tom , who always has a contrary opinion, may not know very many Alaska , or other cold weather pilots. I have used 15-50 shell for years with no problems. I think most FBOs use whatever oil they get the best deal on from the distributor. Incidentally, the porsche 2014 owners manual specifiys 0-40 Mobil one oil which is used by the local dealer.( porsche is, of course, a horizontally opposed boxer engine) porsche has built these type engines for quite a few years.

When Mobil Av1 existed, it was such crap Mobil had to buy a buttload of Continental 520s and they took it off the market. Aeroshell 15/50 Semi Synthetic oil is the the same thing as Mobil 1 mixed with regular oil. There is one synthetic lube oil base stock and everybody uses it IIRC what Ed Collins told me. That is why Aeroshell 15-50 is junk. That base stock is developed for Mogas, not AvGas. The chemical formulations are completely different even apart from the lead aspect, and the synthetic base stock does not deal well with either the by products of combustion or the lead. That's why when you run Aeroshell 15/50 in a Continental, you'll see elevated copper readings on your oil analysis than if you use a regular fossil oil.
 
It'd be nice if someone from Blacksone was here, eh? I'm sure they have quite ample data.
 
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