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Auto fuel why not auto oil?

QUOTE......Essolube Xd3 15w40 (EXXON for you) and Shell's rotella t are designed/formulated for either gas or diesel severe duty , high friction type applications.(flat tappet engines) it does have P and Zn in the add pack along with a bunch of other additives. If you want a spotless engine(internally) being highly protected from wear then use it. The oil certainly doesn't know a lycoming from a cummings. It just cleans and protects. (way better than "aviation" oil). Sorry that the facts. 37 years for Imperial oil looking inside hundreds of disassembled test engines.

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Exxon Xd3 15w40 appears to be discontinued based on an internet search. But Shell Rotella seams to be everywhere...... http://rotella.shell.com/products/rotella-triple-protection.html

Anyone want to give it a try? It will give you a reason to use your new bore scope.
 
Ok, I have been retired from esso for 2 yrs last may.(thankyou god) I just called the lab and we don't manufacture the xd3 oil in Canada anymore apparently. It is now all in the USA and is called Delvac. (my "supply" of xd3 hasn't ran out quite yet LOL) Rotella T is Shell's equivalent. They are made with conventional,crude derived, base oil which is indeed inferior to synthetic base oils but that is not an issue if you change the dang stuff. Under extreme extreme heat and pressure the base oil lube molecules will get thermally cracked into shorter chain molecules that will degrade their lubricating qualities.I completely checked all my oil ,in and out , on every oil change and worked my way up to 60hr intervals. The oil always met new manufacturing specs every time in terms of viscosity and additive levels. In other words could actually go longer but I chose to stay around 60 hrs.
 
The real trick is to keep the moving parts "separated" from each other to prevent excessive wear. A tiny bit of wear on break in is necessary and desirable. Hence we have break in oils which is ok. The additives are what give the oil a lot of it's personality but base oil quality is important as well. For example, 5 weight oil gets into action quicker at start up in cold weather. After break in we want the engine to last forever if possible so wear protection is paramount. Microscopically, the wear additives form an "artificial" layer of material on the moving parts that continually gets removed and replaced as the engine is running. it slowly gets depleted from the mother ship (the base oil). The base oil forms a layer between the surfaces and attempts to keep them physically separated, but this is next to impossible, so that is where the wear additives come in to the picture.
 
The reason I am doing this in small bites is because I seem to lose my comments if I take too long to hit the reply button. The concern about depositing the wear metal additives in the combustion chamber is a valid one IF we are consuming (burning) large quantities of oil. Not sure about you guys but the main place i loose oil is doing rolls which i am addicted to. All my additives get deposited on the belly of my beautiful airplane. I also use a bore scope annually and can see lead deposits in there but I am using avgas. Also on the used oil i am testing we have consistently found high levels of lead in the oil. This type of oil has additives to dissolve/disperse incomplete combustion products in diesel engines so it does an extremely good job of keeping your engine moving parts clean. Also has great anti rust characteristics. I just know it works well so I use it. But everyone has their own beliefs on this topic. (as well as everything else) So as Mark always says , Carry On
 
I use rotella in everything around the farm including the 4 wheelers. I would be so inclined to try this on my rebel, but due to the nature of the RV engine I?ll probably stick with aircraft oil until the rotella proves it can do a good job at removing lead and deposits. I agree rotella does a great job in diesels removing particulates, just not sure how that translates into removing lead. My next oil change in the rebel will be with rotella t6, full synthetic.
 
Ok, I have been retired from esso for 2 yrs last may.(thankyou god) I just called the lab and we don't manufacture the xd3 oil in Canada anymore apparently. It is now all in the USA and is called Delvac. (my "supply" of xd3 hasn't ran out quite yet LOL) Rotella T is Shell's equivalent. They are made with conventional,crude derived, base oil which is indeed inferior to synthetic base oils but that is not an issue if you change the dang stuff. Under extreme extreme heat and pressure the base oil lube molecules will get thermally cracked into shorter chain molecules that will degrade their lubricating qualities.I completely checked all my oil ,in and out , on every oil change and worked my way up to 60hr intervals. The oil always met new manufacturing specs every time in terms of viscosity and additive levels. In other words could actually go longer but I chose to stay around 60 hrs.

Did they say which version of Delvac; Delvac 1 or 1300? Also curious which version of Rotella T is comparable and if Delo 400 also compares. My pops runs Rotella T6 in his pickup, I run Delo 400 in mine and in my gas boat. I've thought about using a diesel oil in my Continental but until now I had not found anyone that thought it was a reasonable idea.
 
Not sure how you would expect engine oil to remove lead from inside your combustion chamber when its not supposed to really be in there in any big way to start with. But it does dissolve it and carry it out of your crankcase where it definitely gets to.
 
Rotella T is what I use in all my "unleaded" and diesel slider cam motors. Except my 2013 VW TDI.....which is now gone (but not forgotten - what a great car) In that I used the 507 motor oil VW specified.
 
Obviously not implying that lead is not in your combustion chamber because that where it is designed to be but don't expect ANY oil to remove it.
 
Doug,

I don't think anyone is expecting the oil to clean lead from the combustion chambers. But the synthetic av oil fiasco a while back seemed to be related to lead building up throughout the engine because the synth oil failed to hold the lead in suspension so it could be drained. I'm assuming that the lead got there because of blowby in our sloppy-loose a/c engines, but I could be wrong. About the whole thing.

Anyway, the question in my mind is whether Rotella or similar auto oils will act like av oil in this respect.

The other issue I've seen raised is the elevated head temps of our air cooled a/c engines, as opposed to water cooled engines. No issues along those lines?

I run mogas almost exclusively, so the lead issue is minor for me, but the head temp issue remains.

What about mixing dyno & synthetic auto oil? Dyno for rust protection; synth 'cause it's super slick....

Charlie
 
Actually any oil that finds it's way into the combustion chamber will tend to add to combustion chamber deposits as the additives won't get completely combusted. This is very minor as next to no oil should be getting in there and some of the unconsumed additives will go out the exhaust. Lead is in the fuel and if you ever flooded your engine (i did on every hot start) then yes, lead gets in the crankcase. Also on initial startup the in complete combustion also puts some there along with a minute amount during normal operation. This lead needs to be removed by the oil which this type of oil will do. As far as temps go, the local temps on the immediate surface of the cylinder will be quite hot in any engine water cooled or not. Same with the temps of the layer of oil between the bearings and rod journals for instance. The local temps there are EXTREMELY high. High enough for thermal cracking to occur. The results of this can be seen in viscosity degradation and possibly coke production. I have never measured any significant visc degradation in use of up to 60 hrs. Oil always met new oil specs. Oil will remove any coke as well as incomplete combustion material. Synthetics won't thermal degrade however and are more lubrisc. I wouldn't mix the two.
 
Same with the temps of the layer of oil between the bearings and rod journals for instance. The local temps there are EXTREMELY high. High enough for thermal cracking to occur.

So just how high do you think the bearing temperatures are? The highest known temps are around the piston and heads, particularly under the piston crown, over the top of the heads around exhaust ports and valve guides. And the oxidation viscosity increase is primarily due to time at temperature of the oil sitting in a high temp sump. Specifically, high power (BMEP) diesel engines.

My experience says the peak oil temps in the bearing flow is not extremely high, but know that the crank pin metal temps are higher than the rods. I don't remember the numbers precisely, but oil temperature rise across the bearings (main and rod) are well under 50 degrees F.

Oh- one other question, how does/do the current Mobil 1 formulation(s) compare to the XD3?
 
Hi Bill.... I just had to call one of the R&D oil experts from work to revisit. Highest temps are indeed around/under the piston. He said temps have been measured (somehow) as high as 350 celius in some engines. Mineral type base oil can get sheared a bit between the bearing and shaft but the thermal oxidation is happening up where you said. He also said that the "coke" deposits i have seen stuck to the engine parts gets produced as some oil gets past the rings, gets burnt and then gets scraped back down into the bottom where the oil has to absorb it. That's where this XD3 oil shines as it can put all that sludge into solution and keep it from falling out on the engine parts. Some oils can't perform that function. He also said that Delvac 1300 super is the same just a different name. Also said they have synthetic version which is even better.
 
Doug,

I don't think anyone is expecting the oil to clean lead from the combustion chambers. But the synthetic av oil fiasco a while back seemed to be related to lead building up throughout the engine because the synth oil failed to hold the lead in suspension so it could be drained. I'm assuming that the lead got there because of blowby in our sloppy-loose a/c engines, but I could be wrong. About the whole thing.

Anyway, the question in my mind is whether Rotella or similar auto oils will act like av oil in this respect.

The other issue I've seen raised is the elevated head temps of our air cooled a/c engines, as opposed to water cooled engines. No issues along those lines?

I run mogas almost exclusively, so the lead issue is minor for me, but the head temp issue remains.

What about mixing dyno & synthetic auto oil? Dyno for rust protection; synth 'cause it's super slick....

Charlie

I run rotella in my Porsche. It is an air cooled boxer engine, very similar in design to a IO-540. Aviation oils have no design features specific to air cooled engines. I would run the Rotella in my IO-320 if I had confidence that it could hold the lead in suspension as well as the aviation oil with it's AD additives. Not saying it doesn't, just no one has told me it does. Diesels have to carry a lot of junk in suspension, but it is not lead, so I remain a bit skeptical.

I will also add that everyone calls our engines "loose" relative to auto engines. However, when I rebuilt my 320, the clearances were pretty much the same as the old Chevy 350's that I rebuilt for my boat. Granted, contemporary engines are likely a bit tighter than the old Chevy small blocks. The ring end gaps appear much larger, but that it due to the odd duck, choke bore. once you account for the taper, it is about the same .030" used in naturally aspirated auto engines. The gap has to be increased as combustion temps increase, but this is unrelated to air or water cooled.
 
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Ir172....One further comment around what I have seen. Originally when I started analyzing my oil at work the technician doing the testing came to me wide eyed with the lead concentration coming back off scale high. This normally would indicate bearing material in the oil. I told him that I was burning av gas. So every time I changed the oil it came back the same. I had him actually quantify it through dilution to get the reading on scale for his calibration curve.It came back at 4020ppm. I think the oil is removing the lead. Also I have seen lycomings with 1000 hrs apart that had used this oil and they were absolutely spotless. So if lead was hanging around and depositing I sure couldn't see any.
 
Ir172....One further comment around what I have seen. Originally when I started analyzing my oil at work the technician doing the testing came to me wide eyed with the lead concentration coming back off scale high. This normally would indicate bearing material in the oil. I told him that I was burning av gas. So every time I changed the oil it came back the same. I had him actually quantify it through dilution to get the reading on scale for his calibration curve.It came back at 4020ppm. I think the oil is removing the lead. Also I have seen lycomings with 1000 hrs apart that had used this oil and they were absolutely spotless. So if lead was hanging around and depositing I sure couldn't see any.

Thanks for the data points here Doug. Good to see some historical experience with this oil. I may do some experimentation with the Rotella or Delvac 1300. Would avoid the excessive costs of aviation oil, mostly due to shipping costs for me.

Larry
 
Would avoid the excessive costs of aviation oil, mostly due to shipping costs for me.

Larry

Just as a datapoint, I purchase Phillips 20W-50 aviation oil from vendors on *Bay and it is ~$75/case delivered to my door. Quality auto oil is going to cost about this much at the local auto parts store.
 
Just as a datapoint, I purchase Phillips 20W-50 aviation oil from vendors on *Bay and it is ~$75/case delivered to my door. Quality auto oil is going to cost about this much at the local auto parts store.

I also pay $75/case. However, at the local menards, a quart of Rotella 15W40 is only $3.50. They used to sell gallons for under $12.00, however, they only seem to stock the 10W30 in gallons now. This is about half the cost.
 
Doug, and Gasman,

The Esso and variants don't seem to be available here in the USA deep south, but Shell Rotella is everywhere. I just started looking at it, based on this thread, and discovered that there are several variants, from basic dyno to synthetic blend to full synthetic, and single weight to multiweight.
http://rotella.shell.com/products.html
Which type do you think is best in a Lyc, and would you pick single weight or multi weight? 'T', T-1, T-4, T-5, T-6? Is Aeroshell 100 (50 weight) heavier than Rotella 40 (are the weight scales the same)? Is 15w40 'thick' enough for the Lyc that's been fed a diet of Aeroshell 100?

I'm not sure of the significance, but Shell's product pages only seem to mention gasoline engines in the 'T-6 Multi-Vehicle' oil description. Any significance to that, or is it just marketing?

Thanks for educating. :)

Charlie
 
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Doug, and Gasman,

The Esso and variants don't seem to be available here in the USA deep south, but Shell Rotella is everywhere. I just started looking at it, based on this thread, and discovered that there are several variants, from basic dyno to synthetic blend to full synthetic, and single weight to multiweight.
http://rotella.shell.com/products.html
Which type do you think is best in a Lyc, and would you pick single weight or multi weight? 'T', T-1, T-4, T-5, T-6? Is Aeroshell 100 (50 weight) heavier than Rotella 40 (are the weight scales the same)? Is 15w40 'thick' enough for the Lyc that's been fed a diet of Aeroshell 100?

I'm not sure of the significance, but Shell's product pages only seem to mention gasoline engines in the 'T-6 Multi-Vehicle' oil description. Any significance to that, or is it just marketing?

Thanks for educating. :)

Charlie

Hopefull Doug will input, but from my research, you only want the variants spec'ed for diesel. I used the Rotella T 15W40 (labeled as Rotella T Triple protection). That is a diesel oil and you'll see SPI specs like CI-4, CJ-4, etc. Avoid any that don't have diesel specs. Diesels need additives to hold soot in suspension, like our lead, and the automotive gas engines don't need to hold that much in suspension, relative to diesels. I would avoid their multi-vehicle variants. Only the heavy duty diesel oils. I would be suspicious of any of the oils that are 10Wsomething, as diesels don't usually spec that low.

100 aviation oil is a 50 weight oil. However, I don't see why a good quality 40 weight oil. like 15W40 wouldn't survive just fine in our application. Lot's of folks use 80 aviation oil, which is a 40 weight oil. A 20W50 oil is probably only providing a 45 weight viscosity after 50 hours anyways.

Larry
 
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