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Oil Type for O360 A1A Summer/Winter

Prepperpilot

Well Known Member
Now I don't want to start a battle royal here about oil opinions. But I live in Ohio so it can get cold. Should I run different oil type summer/winter. Previous owner did not make any change.
I have a 180HP O360 A1A RV8
Any advice is appreciated on oil brands and types. Thank you.
CHeers
Chris
 
Phillips XC multi weight works good out here! Pretty much everyone uses it where I live.
 
For the winter I would use 15-50.. it is semi synthetic, and it also contains the Lycoming additive that the “Plus” oils have. You can then continue to use it all summer too!
 
What are the thoughts on Phillips Victory 20-50? I have been using that but I only have 80 hours on the engine so not much experience since the first couple changes were mineral oil!

I am in Michigan - it was 1 degree this morning!! Ugg.
 
Any thought on Aeroshell W100 plus. That's oil I use currently.

i use 100W plus. my engine has just 150 hours but i never saw any debris in the filter at oil changes (except a little bit at first filter change after brake in with straight aeroshell 100). so it seems to work. though i preheat when it's cold.
 
Any thought on Aeroshell W100 plus. That's oil I use currently.

This SHOULD NOT be used in Midwest winter climates! An exception would be someone that never starts the engine without using an oil pre-heater. However, what if you go somewhere with the plane and need to start the next morning at 20* OAT; W100 will be like syrup. The Lycoming manual gives acceptable ranges for various weights and temps.

Simply All upside and no downside to using multi-vis oil in colder climates. There is a reason that no autumobile engine has specified a straight weight oil in 40+ years, excluding racing or other special circumstances.

Larry
 
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W100 plus

Another Data Point: I use Aeroshell W100 plus and have had no issues. But, I do have a full Tanis preheat system on my Aerosport Power IO-375-M1S. I also have my airplane hangared right on the Chesapeake Bay.
 
Another Data Point: I use Aeroshell W100 plus and have had no issues. But, I do have a full Tanis preheat system on my Aerosport Power IO-375-M1S. I also have my airplane hangared right on the Chesapeake Bay.
Yup. I have preheat for oil pan also. Keeps it at steady 70df. I have not noticed any strange oil consumption.
But you guys have given me something to think about.
I do remember however opening a cold quart of w100 plus. It was very gelatinous for sure. Thick as pudding.
 
I switch to Multi XC20-50 in the winter months then back to AS W100 when it gets warm with a little Camguard just for grins.
 
I switch to Multi XC20-50 in the winter months then back to AS W100 when it gets warm with a little Camguard just for grins.

Why switch from Philips to AS and back? Why not use AS15w50 or Philips 100 Victory oils?
 
What's the benefit to a single weight oil (or the drawback of a multiweight) in the summer?

Call me old fashioned but I just prefer the single weights when the temps allow (which is most of the time in TX).

Why switch from Philips to AS and back? Why not use AS15w50 or Philips 100 Victory oils?

The AS15w50 is a synthetic mix and although I'm sure it's a good oil, I prefer to stick with the mineral blends for aircraft engines.
Is AS better than Victory, no idea, old habits die hard is all.
 
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What's the benefit to a single weight oil (or the drawback of a multiweight) in the summer?

what i understood is that thicker oil lubricates better when it's warm enough. another benefit is that it's more sticky and therefor coats the internal engine components after shutdown longer ==> better corrosion protection.

well, there has to be a reason that this thick stuff is around. i do believe when using preheat regularly you're better off with high viscosity oil. otherwise use thinner oil.
 
what i understood is that thicker oil lubricates better when it's warm enough. another benefit is that it's more sticky and therefor coats the internal engine components after shutdown longer ==> better corrosion protection.

well, there has to be a reason that this thick stuff is around. i do believe when using preheat regularly you're better off with high viscosity oil. otherwise use thinner oil.

What leads you to believe that 50 weight oil is thicker than 20w50 oil? Once above approximately 125 degrees, both oils should have the same viscosity. It is still out there because people keep buying it. I would argue that most buying it don't know why they are buying it over multi-vis oil, beyond habit.

The benefit is that multi-vis is thin when cold and thick when warm. It's only downside is that the viscosity modifiers can wear out over time. However, that is on the order of hundreds of hours of use and doesn't apply to us with our short drain intervals.

I cannot think of a single additional benefit to straight wt oil and most engine manufacturers would agree and why they don't specify it anymore.

On the subject of "cling" I believe that more than just viscosity is required. Look at the additives in gear lube for examples. Even the 90 wt gear lubes use additives to promote cling.


Larry
 
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@KayS.

Listen to Larry. Not a debate but someone will disagree on anecdote. Most present the argument for multi-weight oils as their ability to flow and subsequently protect when cold. Depending on what stats or studies you read, a majority, vast majority, or more of the wear associated with friction comes from start-up, warm up. Many newer cars utilize 0Wxx oils.

I've said many times that designing a component or system for a single set of conditions isn't that hard (go way, way back to the discussion on cylinder temps you were part of). I'm ME. Now let the ChemE's or Petroleum Engineers weigh in and we'll see if the same is true regarding this art. I know which way to bet and will lay odds.
 
What's the benefit to a single weight oil (or the drawback of a multiweight) in the summer?

Just a quick browse through Aircraft Spruce, I'm seeing a slightly lower cost for single weight oils. Besides cost, I don't know of any benefits to to single weight oil.
 
Larry/Scott: that means the only advantage of single weight oil is being a buck or so cheaper per can?

did not know that. if so i will consider changing to multi weight. have to place an order for new oil anyway.
 
This is another point where fear/superstition/tribal knowledge/old facts will stir up a very old dabate. Some of the early semi-syns were believed to be good at desludging crankcases. Some blame for engine failure was Placed on the switch. The formulations have changed through the decades. Whatever brand you end up moving to, follow that OEM’s recommendations (if any). I personally would do a very short interval after the switch just so I could have a look. Fear and superstition on my part but it’s cheap piece of mind. Let us know. Best of luck.
 
multi-vis for sure

I am firmly in the multi-vis court. Wouldn't use single unless it was given to me and then only in the summer.
My three cents worth Art
 
Oil analysis over the years

Since 2013 when I bought my first RV, an RV-4 and started flying and maintaining my own airplane, I wanted some analysis behind my decisions. Oil analysis supported running that O-320 well past TBO, I think it is still humming along nicely for the new owner at over 2500 hours.

I started using Phillips 20W-50 with CamGuard added. I did a lot of reading and listening to those that claimed to know oil. I change my oil at the interval recommended by Lycoming, to remove the contaminants in the oil (lead, moisture, etc) and send off a sample to Blackstone.

The last 8 years of oil changes in four different engines has consistently yielded these layman's casual observations:

1. Blackstone reports excellent wear based on the metals and quality of the oil found in my oil samples, usually after about 25-35 hours on the oil average. After I own and fly regularly, then change the oil regularly, it is amazing how the oil samples show how engines settle in consistently with this care procedure.

2. The Phillips multi-viscosity seems to be easy starting and consistent all year round. Each engine seems to run about 180*F though it takes a bit longer to get there in the winter in the Cub. The RV is getting an adjustable oil cooler vane soon, but in the past I've simply covered about 2/3 of the oil cooler with an aluminum plate I can insert during a fall oil change and take it out again during the Spring oil change.

3. No synthetics. Maybe the videos from Mike at Savvy Aviation explain it best... the lead in our engines from piston ring blowby is not compatible with any synthetic oil. I had a choice to try to find MOGAS or simply not run synthetic or semi-synthetic oil. I stay away from Aeroshell and Exxon oil that contains any synthetic for that reason.

4. A nice side benefit is that Phillips is widely available and a couple dollars per quart cheaper. I don't mind changing my oil and filter every three months. I get to take a look under the cowl and keep an eye on my engine since I fly IFR, over mountains and occasionally at night.

I hope those are quantifiable and measurable reasons why I use the oil I use. If we ever get a no-lead option that works with angle valve engines or at least MOGAS more common at my local airports (South Carolina) for the lower compression engines, like my wife's J-3 Cub with the A-65, then maybe that engine could benefit from a synthetic or semi-synthetic.
 
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3. No synthetics. Maybe the videos from Mike at Savvy Aviation explain it best... the lead in our engines from piston ring blowby is not compatible with any synthetic oil. I had a choice to try to find MOGAS or simply not run synthetic or semi-synthetic oil. I stay away from Aeroshell and Exxon oil that contains any synthetic for that reason.

That's interesting. I had always assumed any multi-vis had to contain some synthetics; e.g. at the least, the viscosity modifiers that Larry mentioned had to be synthetic. I cannot conceive of how blending distillates (if that's the right terminology) can invert the typical temperature versus viscosity properties.

Willing/wanting to learn if someone skilled in this art can explain. It would surely be appreciated
 
That's interesting. I had always assumed any multi-vis had to contain some synthetics; e.g. at the least, the viscosity modifiers that Larry mentioned had to be synthetic. I cannot conceive of how blending distillates (if that's the right terminology) can invert the typical temperature versus viscosity properties.

Willing/wanting to learn if someone skilled in this art can explain. It would surely be appreciated

A conventional oil uses conventional oil stocks. Synthetic oil uses synthetic oil stocks. Additives, including viscosity modifiers, are almost universally synthetic based, but does not change the classfication of the oil, which is based upon the stock used and not the additives.

Larry
 
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Mike Busch

The above is a nice summary of what's discussed in more detail in his book Mike Busch on Engines which I highly recommend. One of the main takeaways for me after reading that is that the whole straight weight vs multi-weight argument is not that straightforward nor is it about just saving a buck. There are plenty of variables depending on where and how you fly that can make the case for one versus the other. I say, read that then decide what's going to work best for you.
 
Oil

My big takeaway from the Mike Busch information is that multi grades drain off the internal components much faster after shutdown. I am using 100W plus for that reason. I want the better protection for the camshaft when the airplane is sitting for several weeks.
 
My big takeaway from the Mike Busch information is that multi grades drain off the internal components much faster after shutdown. I am using 100W plus for that reason. I want the better protection for the camshaft when the airplane is sitting for several weeks.

I never understood this argument, not saying it isn't true just don't understand it.
If 100 weight oil is the same viscosity as 20W50 at normal engine operating temps would not both oils have the same viscosity and therefore run off the parts at roughly the same rate? I wonder if there has been any testing done and actual data showing how many more hours, days, or weeks coverage the straight weight oil provides as the engine cools.
 
OIL

It's the synthetic portion of multi grade Aeroshell and Exxon that Mike Bush does not like. Phillips multi grade does not have the synthetic portion but is straight mineral oil.
Apparently Busch feels that the Aeroshell and Exxon does not stay on the internal parts as well as single grade because of the synthetic portion. OK for airplanes that fly a lot but not good for airplanes that sit for long periods of time.
 
I never understood this argument, not saying it isn't true just don't understand it.
If 100 weight oil is the same viscosity as 20W50 at normal engine operating temps would not both oils have the same viscosity and therefore run off the parts at roughly the same rate? I wonder if there has been any testing done and actual data showing how many more hours, days, or weeks coverage the straight weight oil provides as the engine cools.

Yes, the guy at camgaurd did a test. St wt and multi-vis behaved the same. Cam gaurd extended drip off time by a couple of weeks. Further proves that additives are required for "cling." Mike tends to treat anecdotal data a fact. Use caution.

Larry
 
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