How quick does your oil turn dark?

What in the world does a refinery operator, however accurate that description is, know about chemistry of oil blends? Maybe what valve to open and close but chemistry? Doubt it.
How about we get back to aviation?
 
Engineers are human. I've found mistakes they've made. I've argued with them before, last time being: I told the engineer he needed to write an Engineering Authorization for a structural blendout that was out of limits, he argued that it was within limits and that I didn't understand the math to make that determination, so no EA was required. Told him it's my name on it, not his. He submitted the findings to Boeing and they authorized a one time ferry flight for repair.
 
Tom-D said:
What makes this thread is any different than any other thread in this forum?
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Nothing, but that doesn't make it right. Make no mistake, I'm not picking on just you, Tom.

For all of you guys' vast knowledge about the chemistry of various oils, you sure can't seem to stay on topic. I think it's fairly obvious that I have some concern about my Aeroshell W100 turning dark so quickly, and that my goal is to come to some conclusion about whether it could be the start of an issue or nothing to worry about, based on what my peers experience with their engines/oils. The lengthy conversation about lipids, whale oil, synthesis, blending, and all the other chemistry doesn't have a lot to do with my Aeroshell W100. At least I failed to make the connection if it did. I believe that all you cats have very useful knowledge to share, which is why I'm here, but the arguments just make me want to ignore my own thread. Yes, it happens a lot on POA, but that's not good justification to continue the practice.
 
Try Phillips XC next oil change. It's approved in your engine so no risk and it's less expensive than Aeroshell. Take some of the leftover money and replace that Brackett with a Donaldson air filter. Better oil, better air filter... see if it makes any difference in your airplane. That's the best indicator you can ask for.
 
OkieFlyer said:
Nothing, but that doesn't make it right. Make no mistake, I'm not picking on just you, Tom.

For all of you guys' vast knowledge about the chemistry of various oils, you sure can't seem to stay on topic. I think it's fairly obvious that I have some concern about my Aeroshell W100 turning dark so quickly, and that my goal is to come to some conclusion about whether it could be the start of an issue or nothing to worry about, based on what my peers experience with their engines/oils. The lengthy conversation about lipids, whale oil, synthesis, blending, and all the other chemistry doesn't have a lot to do with my Aeroshell W100. At least I failed to make the connection if it did. I believe that all you cats have very useful knowledge to share, which is why I'm here, but the arguments just make me want to ignore my own thread. Yes, it happens a lot on POA, but that's not good justification to continue the practice.
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As has been said before, oil only turns black for two reasons, It is being contaminated by carbon, or it is being burned into carbon.

I can not tell from here what your engine is doing, neither can any one else.
 
OkieFlyer said:
Nothing, but that doesn't make it right. Make no mistake, I'm not picking on just you, Tom.

For all of you guys' vast knowledge about the chemistry of various oils, you sure can't seem to stay on topic. I think it's fairly obvious that I have some concern about my Aeroshell W100 turning dark so quickly, and that my goal is to come to some conclusion about whether it could be the start of an issue or nothing to worry about, based on what my peers experience with their engines/oils. The lengthy conversation about lipids, whale oil, synthesis, blending, and all the other chemistry doesn't have a lot to do with my Aeroshell W100. At least I failed to make the connection if it did. I believe that all you cats have very useful knowledge to share, which is why I'm here, but the arguments just make me want to ignore my own thread. Yes, it happens a lot on POA, but that's not good justification to continue the practice.
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You are comparing your engine oil with others under exact same conditions, same engines with same hrs., with same internal components, in same airframe, under exact conditions at oil change so they are all hiding the same amount of dirty oil?
 
Stewartb said:
Try Phillips XC next oil change. It's approved in your engine so no risk and it's less expensive than Aeroshell. Take some of the leftover money and replace that Brackett with a Donaldson air filter. Better oil, better air filter... see if it makes any difference in your airplane. That's the best indicator you can ask for.
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I'd start with that, plus knowing what his CHTs, plus his oil usage would help, and the time on the ring set.
 
Tom-D said:
I'd start with that, plus knowing what his CHTs, plus his oil usage would help, and the time on the ring set.
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CHTs - 330°F (post #4)
Oil usage is about 1 qt per 6 hrs. (post #30)
615 hours on the rings
 
GlennAB1 said:
You are comparing your engine oil with others under exact same conditions, same engines with same hrs., with same internal components, in same airframe, under exact conditions at oil change so they are all hiding the same amount of dirty oil?
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Nope. Thank you.
 
OkieFlyer said:
Oil usage is about 1 qt per 6 hrs. (post #30)
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That's higher than anything (even beater rentals) I've ever flown in 25 years, but I also know from reading stuff here, that it's fairly common.

I would imagine if that's caused by blow-by the oil would get dirty fast.

But I'll leave real answers to all the arguing experts. Haha. [/QUOTE]
 
Look, Glenn and Tom, there are a bunch of people on POA that fly airplanes and have changed their oil many, many times. I've changed airplane oil exactly twice. It looks quite a bit darker than I'm used to seeing oil after just a few hours, but I'm used to cars, boats, atvs, etc. I'm also not used to straight weight mineral oil. I don't know what to expect, okay. For all I knew, I could have had 20 people chime in and report that it's totally common to have black oil after 5 hours, or 20 people could have said, dude, you need to get that checked out. I just don't know these aircraft engines very well yet. I'm a newbie, and I'm trying to glean some knowledge from folks with experience. It's my first airplane, it's 54 years old, I've only put 50 hours on it, so I'm a bit of a worry wart at this point. We're still just getting acquainted.

P.S. There hasn't been any visible metal in the oil or filter on the oil changes I've done.
 
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I could take a picture of our dipstick if it would help. We're probably about 10 hours since our last change, I'd have to look in the book and it's in the airplane.
 
denverpilot said:
I could take a picture of our dipstick if it would help. We're probably about 10 hours since our last change, I'd have to look in the book and it's in the airplane.
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That's alright, man. I appreciate it though. I'm just going to change the oil early and see what happens next.

I actually did go about 8-9 hours without needing to add on the Oshkosh trip. 6 hrs is more typical, but I'm usually flying a bunch of 1 hour or less flights with a bunch of take-offs per flight hour rather than cross country where I spend a lot of time in cruise. I don't know. I just need to go fly more and figure it all out with experience. Thanks hanging with me here, Denver, and thanks for the help.
 
OkieFlyer said:
Thanks hanging with me here, Denver, and thanks for the help.
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Ahh no worries. When we were new owners we kept pouring oil into ours trying to keep it at the top mark until we learned and realized that it was just blowing overboard and a huge mess on the belly to clean up.

Now we know where it doesn't do that and we don't overfill. I still email co-owners and we agree if we are going to add some, that's how little ours burns/blows between changes.

Plus colors are hard without photos. One man's "black" is another man's "looks ok to me".
 
Well....I learned pretty quickly that it'll blow out anything over 9 qts onto the belly rather quickly. The oil usage I'm talking about is starting from the 9 qt mark, not full (12qts).
 
GlennAB1 said:
It's good, you're concerned. Is there anything in any manuals that drives you to be concerned with oil darkening too quickly?
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Not that I've seen thus far. I just figured that the darker it is, the more used up it is, and if I'm supposed to change it at 25-50 hours, it's gonna be jet black by then at this rate. I would be concerned if any of my other internal combustion engines turned dark that fast, but as I said, I'm new to aircraft engines. I'll just keep an eye on it. It doesn't smell burnt or anything at this point.
 
Tom-D said:
You most likely don't know I worked 4 years at the Shell refinery as a operator, you don't get that position with out taking all the company training.

And for Clark,, I didn't make up the web page that proves you wrong.

For the rest of ya, semi synthetic oil we use in our engines is a blend of nature petroleum oil and a synthetic oil produced by other means. with a brand name additives. some for corrosion protection, some for wear. what ever the brand name companies want.
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Which web page was that?

You most likely don't know that I have taught petroleum engineering at two universities. You are still welcome to offer an apology at any time.
 
OkieFlyer said:
Not that I've seen thus far. I just figured that the darker it is, the more used up it is, and if I'm supposed to change it at 25-50 hours, it's gonna be jet black by then at this rate. I would be concerned if any of my other internal combustion engines turned dark that fast, but as I said, I'm new to aircraft engines. I'll just keep an eye on it. It doesn't smell burnt or anything at this point.
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We change oil at 25 or 50 hour intervals because ashless dispersant oils become contaminated and by design the contamination is designed to remain suspended in the oil. Filters remove particles but not dissolved contaminates. When the contaminated oil is paired with moisture it becomes corrosive. That's why we try to "burn off" moisture by flying often with oil temps >180*. Assume you elect to change oil at 50 hours. Will your oil be more contaminated/more corrosive than it was at 25 hours? Judging by your comments about oil coloration and blowing out oil above the 9qt mark almost certainly. Would it be wise to change oil at 25 hours? Almost certainly. Would it be interesting to try a different oil that many pilots have found beneficial for reducing the coloration and blow-by? It seems like a good plan to me.

Seriously, try Phillips XC. The average 0-470 owner will see his oil stay cleaner and will be able to run more oil in the crankcase without blowing it out. (I run my own 0-520 with 10qts plus a pint of Camguard and don't consume enough oil to add between oil changes. I couldn't say that when using Aeroshell.)
 
Stewartb said:
We change oil at 25 or 50 hour intervals because ashless dispersant oils become contaminated and by design the contamination is designed to remain suspended in the oil. Filters remove particles ut not dissolved contaminates. When the contaminated oil is paired with moisture it becomes corrosive. That's why we try to "burn off" moisture by flying often with oil temps >180*. Assume you elect to change oil at 50 hours. Will your oil be more contaminated/more corrosive than it was at 25 hours? Judging by your comments about oil coloration and blowing out oil above the 9qt mark almost certainly. Would it be wise to change oil at 25 hours? Almost certainly. Would it be interesting to try a different oil that many pilots have found beneficial for reducing the coloration and blow-by? It seems like a good plan to me.

Seriously, try Phillips XC. The average 0-470 owner will see his oil stay cleaner and will be able to run more oil in the crankcase without blowing it out. (I run my own 0-520 with 10qts plus a pint of Camguard and don't consume enough oil to add between oil changes. I couldn't say that when using Aeroshell.)
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Thank you, Stewart. That's extremely helpful info.

So, why did more Aeroshell blow out? Does it not seal the rings as well? Because of the contamination or just the nature of the oil?
 
GlennAB1 said:
Thought it was funny you did that while pointing out someone else's lacking competency.
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I never claimed to be a perfect speler. Do you have anything of substance? ever?
 
Stewartb said:
Seriously, try Phillips XC. The average 0-470 owner will see his oil stay cleaner and will be able to run more oil in the crankcase without blowing it out. (I run my own 0-520 with 10qts plus a pint of Camguard and don't consume enough oil to add between oil changes. I couldn't say that when using Aeroshell.)
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So why would your observation with a completely different engine and oil system necessarily apply at all? Just curious.

We see zero overboard and don't have to add anything between changes as long as we stay slightly below the top mark on the stick on an actual O-470, go figure. Seems like it's just a quantity thing.
 
My 0-520 is an 0-470 with bigger cylinders. It was an 0-470 before I did the mod. Same case, same oil system. The Phillips advantage isn't limited to the 470/520 family. It's been true for other engines I've had as well. These days I use XC for break-in, too.

Okie, I don't presume to know why Phillips XC works better than Aeroshell for the conditions I mentioned. I'm just giving you a pirep and I'm pretty confident that you'll see similar results. I remember when I asked the same questions you're asking so I offered my experience.
 
Stewartb said:
My 0-520 is an 0-470 with bigger cylinders. It was an 0-470 before I did the mod. Same case, same oil system. The Phillips advantage isn't limited to the 470/520 family. It's been true for other engines I've had as well. These days I use XC for break-in, too.

Okie, I don't presume to know why Phillips XC works better than Aeroshell for the conditions I mentioned. I'm just giving you a pirep and I'm pretty confident that you'll see similar results. I remember when I asked the same questions you're asking so I offered my experience.
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It's much appreciated. Thanks.
 
Clark1961 said:
Which web page was that? Proving you don't read before you answer.

You most likely don't know that I have taught petroleum engineering at two universities. You are still welcome to offer an apology at any time.
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As the old statement says," those who can do, do. those who can't, teach.
 
GlennAB1 said:
That's great, however, that didn't/doesn't make you privy to proprietary information that an employee such as "Tom" could have been privy to.
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In the refineries we don't invent formulas, we do blend various oils to create brand name oils to be caned at different canning facilities, we are talking trainloads of lube oils.
 
9617853.jpg
 
flyingriki said:
What in the world does a refinery operator, however accurate that description is, know about chemistry of oil blends? Maybe what valve to open and close but chemistry? Doubt it.
How about we get back to aviation?
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You learn the chemistry so you know what button to push that will open/close the proper valve. I didn't invent any formulas, but I do know the difference between blending and all other proce
OkieFlyer said:
Glen, Tom, Clark, if you aren't going to add anything helpful to this discussion, GET OUT!!!!
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already did , but I'm out anyway.
 
OkieFlyer said:
Glen, Tom, Clark, if you aren't going to add anything helpful to this discussion, GET OUT!!!!
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If you don't like thread creep, do some thing about it.
btw the administration won't
 
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