Is it absolutely necessary to run a brand twice for a UOA?

Not if you run the oil out to 10,000 miles or more versus 5000 miles for Pennzoil. I know HPL is a sponsor, but I am running there 10W-40 CK-4 oil in my riding mower, and it seems like I am using less fuel versus the 10W-30 Shell Rotella 10W-30

After a mowing the fuel tank was maybe below half a tank or so, now after a mowing the fuel tank is at 3/4ths a tank. I know my observation is not scientific. I am plotting oil temperature readings after each mowing even though that might not mean much.

Pennzoil had there day here and they failed IMO? Mobil 1 is still ok in their Euro Line to a certain extent, now we have HPL that does not cut any corners.
I sent my oil filter for analysis. If I find some stuff in my filter then I will have a genuine reason to switch to HPL. Otherwise not worth it IMHO. Mobil 1 EP 0w20 is more than capable of 10,000 mile OCI and it costs 1/4th the price of HPL. I ordered a case for a good price.

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I sent my oil filter for analysis. If I find some stuff in my filter then I will have a genuine reason to switch to HPL. Otherwise not worth it IMHO. Mobil 1 EP 0w20 is more than capable of 10,000 mile OCI and it costs 1/4th the price of HPL. I ordered a case for a good price.

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Your oil filter will not show anything. JMO The oil you are using is only capable of 10K under the right conditions. If you are only going to keep this car for a short time, keep doing what you are doing. The oil you are using is not even comparable to the HPL Oil that you once used.
 
Your oil filter will not show anything. JMO The oil you are using is only capable of 10K under the right conditions. If you are only going to keep this car for a short time, keep doing what you are doing. The oil you are using is not even comparable to the HPL Oil that you once used.
Mobil 1 got me to 200,000 miles. I used HPL only once, as an experiment to see whether my engine is actually clean or not.
This is my van, the filter was sparkling clean. If the HPL filter is also like that, then I have no interest in HPL whatsoever. Many Toyotas have hit the million mile mark, and none of them used Boutique oils

 
Pennzoil had there day here and they failed IMO? Mobil 1 is still ok in their Euro Line to a certain extent, now we have HPL that does not cut any corners.
How did Pennzoil fail? I never quit running it since I started on this site in like 2011. No major failures in anything due to oil. I’m pretty sure they’re still meeting all recent specs and selling tons of product.

Or are you saying it’s just not the flavor of the month anymore?
 
How did Pennzoil fail? I never quit running it since I started on this site in like 2011. No major failures in anything due to oil. I’m pretty sure they’re still meeting all recent specs and selling tons of product.

Or are you saying it’s just not the flavor of the month anymore?
Pennzoil Ultra was a really good oil and then they changed the formula, I feel like they cut corners.
 
It’s sometimes recommended to do a double oil change before a UOA on a new type of oil, so after 500 miles on a new type I change it again. A more reasonable approach would probably be just to wait for a second full oil change interval before doing a UOA. The double change is what a popular oil-related YouTube personality says to do and he is losing money by saying that since it’s a skipped UOA for him.

On the efficacy of UOA: oil analysis was squeaky clean in this engine, but I found this problem with an exhaust valve after a failed leak-down check at 40/80 and borescope. Lapped the bottom of the valve & seat in place with permatex valve grinding compound and got it back to 77. Of course this is an air cooled airplane engine….after 3 hours still holding at 77. Hopefully the clean UOA means the valve was not yet shedding material, which is probably why the lapping was successful. Lycoming IO-360 air cooled airplane engine at 550 hours since new.

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It’s sometimes recommended to do a double oil change before a UOA on a new type of oil, so after 500 miles on a new type I change it again. A more reasonable approach would probably be just to wait for a second full oil change interval before doing a UOA. The double change is what a popular oil-related YouTube personality says to do and he is losing money by saying that since it’s a skipped UOA for him.

On the efficacy of UOA: oil analysis was squeaky clean in this engine, but I found this problem with an exhaust valve after a failed leak-down check at 40/80 and borescope. Lapped the bottom of the valve & seat in place with permatex valve grinding compound and got it back to 77. Of course this is an air cooled airplane engine….after 3 hours still holding at 77. Hopefully the clean UOA means the valve was not yet shedding material, which is probably why the lapping was successful. Lycoming IO-360 air cooled airplane engine at 550 hours since new.

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What kind of regulations does the FAA impose on engines that have early issues between scheduled rebuilds? Do you have to report it to the manufacturer or the FAA?
 
What kind of regulations does the FAA impose on engines that have early issues between scheduled rebuilds? Do you have to report it to the manufacturer or the FAA?

It’s normal to need to remove and overhaul/replace cylinders between rebuilds. They are built in a modular fashion so that it only takes a few hours or even less to take a cylinder off. I think more than half of new or recently overhauled small airplane engines up needing some kind of “top end” work well before the 1500-2500 hour schedule time before overhaul. Normally an A&P mechanic has to do this kind of work but my engine is classified as experimental so I can do it myself. I do the work under the supervision of A&P’s and one of them is who told me about the rope trick to lap the valve in place. I had to fill the cylinder with rope through a spark plug hole to keep the exhaust valve from falling in until I could attach a cordless drill to the valve stem with 3/8” vinyl tubing for the lapping. Came in through the other, bottom spark plug hole with a bent 6” applicator pad and used the scope to put it under the valve.
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That's the thing, though. You can't really judge anything by a UOA except if the oil is still good for service.
Patently untrue. I tire of seeing this repeated so very often on BITOG. It is a narrowly focused viewpoint which ignores much else.

There are many reasons to use UOAs.
- track normal wear averages, deviations and trends (micro data analysis)
- compare/contrast individual data points to large sample sets which have established steady averages, deviations and trends (macro data analysis)
- observe for abnormal events (relative to the averages, variation and trends mentioned above)
- monitor contamination sources such as fuel from leaking injectors (or poorly tuned carb), silica from intake issues, coolant from various sources
- monitor the physical condition of the lube such as vis, FP, oxidation, NOACK, etc
- monitor the additives in the lube (those which can be seen by the ICP or other tech) such as Ca, Mg, Ti, etc



Tiny variences in wear metals between different oils are just statistical noise and tell you nothing about how well they are doing their job.
Those "tiny variences" (sic) matter. And while they are not something to get excited over in small quantity, they most certainly have effect in statistical analysis. Further, UOAs have, time and time again, successfully predicted an oncoming catastrophic event; we've seen the UOAs here to prove it. That does not mean they will always detect such an event, but to believe they are incapable of doing so is a near-sighted blunder.

UOAs can be studied in either a macro sense, or a micro sense. (See the "normalcy" article in the UOA subforums). The error which the majority of folks using UOAs commit is ignoring the topic of proper statistical analysis methodologies and limitations. One UOA sample (or a few, or even several) are NOT enough data to make comparative superlative performance decisions. The inaccuracy of calculating the stdev is absurdly high when small sample sets are in play. Those are what you imply when you speak to the variation quoted above.

It is true that UOAs only see a portion of the wear particles; they cannot see above 5um as a generalization. So they do not see ALL wear. What they see is a sample representation of wear.

Many SAE articles/studies have shown that UOA data indicates good correlation with other methods of tracking wear, such as component weight analysis, electron bombardment, etc. Further, UOAs have shown good correlation to particle count loading.


The main problem with UOAs isn't the technology or the data. It's that folks don't understand the methodology of how to properly use the tool, and what its limitations are. Don't blame the tool (UOA) for a lack of proper analysis techniques; rather, blame the user.
 
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