HPL SAE 40 PCMO

[Hohn]

Isn't that "stiction"? I remember that word because an engineer inspected a failed hemi cam and used that word, basically saying the oil did not have enough stiction so there was excessive play/slip between cam lobe and lifter.

Slide-to-roll ratio would probably be more correct.

SRR is a common indicator of traction.

Traction is basically the shear force a thin lubricant film can transmit Before any significant slip occurs.

Think of two flat plates with a drop of oil between them. Sliding one across the other you will experience traction in the oil.

 

[Hohn]

Looks to be a term used to describe a system level of friction based on all factors involved, like oil formulation, dynamic viscosity, shear rate of the oil, load on the moving parts (which relates to the level of contact and resulting MOFT) and what realm of lubrication. In pure hydrodynamic lubrication, the moving surfaces contact factor is gone. In boundary and mixed lubrication, the anti-friction additives can also play a role when the surfaces are physically rubbing. Basically it's a term for "What's the overall friction level between two moving parts affected by all factors involved".

My understanding is that traction is only in the context of full elasto-hydrodynamic lubrication

 

[ZeeOSix]

My understanding is that traction is only in the context of full elasto-hydrodynamic lubrication

Digging around, looks like elasto-hydrodynamic lubrication (EHL) only occurs in specific engine components that are highly loaded and have rolling/sliding movement like roller ball bearings (not many if any in ICE), gear teeth, cam lobes/followers, Pin/bushing areas of timing chain(s). Estimates are the EHL in a typical ICE only contribute 5-15% of all engine friction, so not a big factor overall. The hydrodynamic realm is the greatest and the mixed realm next with EHL being the smallest factor.

 

[Hohn]

Right, traction should apply to full hydrodynamic also. I should have said traction is only EHD and farther to right on Stribeck.

I’m not thinking clearly at the moment as my brain is cooked, so I appreciate any correction or clarification you can provide.

 

[Hohn]

1000 mile update. Houston, we have dilution. But do we have a problem? The wear rate is progressing at a whopping 1ppm FE/1k. The add packs is essentially untouched. The TBN is quite healthy, as you'd expect with only 1k miles. It's fascinating to me that I'm at 3.7% dilution in only 1k miles when before I was a this level in about 4500 miles on prior OCIs.

This could indicate what many of you have noted about dilution stabilizing and not climbing. This kind of trending is why I'm collecting so frequent samples on this SAE 40 experiment.

The oxidation and nitration value seems to be wrong. 4400 miles over winter gives a nitration of 14, but 1k miles in springtime and I'm already up to 13? And that oxidation value is clearly not correct. I've requested a re-run. +17 oxidation in 1k miles with almost any oil is all but impossible, never mind with premium GTL bases and the HPL add pack, even with higher dilution.

I certainly did not expect to see dilution this high this early. And I have every reason to think that oxidation value is a lie, but we'll see what Polaris says in response to my request for re-run.

 

[ZeeOSix]

It's fascinating to me that I'm at 3.7% dilution in only 1k miles when before I was a this level in about 4500 miles on prior OCIs.

The UOA says the fuel dilution was 1.2% with 8 miles on the oil sample. What?

I take it that samples 3 and 4 are the HPL SAE 40, and sample 3 was the baseline right after changing to the SAE 40.

 

[Overfill]

Fuel dilution can stabilize, yes. Engine cycle times, fueling settings, and carburetion/injection setup are dominating factors. Something not often discussed is the difference in separability of heavy gasoline fractions from lubricant as a function of the lubricant blend, specifically the base oil and base oil viscosity.

 

[Hohn]

The UOA says the fuel dilution was 1.2% with 8 miles on the oil sample. What?

I take it that samples 3 and 4 are the HPL SAE 40, and sample 3 was the baseline right after changing to the SAE 40.

Correct. The 1.2% was baseline for the monograde.

 

[Hohn]

Fuel dilution can stabilize, yes. Engine cycle times, fueling settings, and carburetion/injection setup are dominating factors. Something not often discussed is the difference in separability of heavy gasoline fractions from lubricant as a function of the lubricant blend, specifically the base oil and base oil viscosity.

There’s probably something to that —a gtl monograde 40 is probably not a comfy house for fuel.

 

[kschachn]

Fuel dilution can stabilize, yes. Engine cycle times, fueling settings, and carburetion/injection setup are dominating factors. Something not often discussed is the difference in separability of heavy gasoline fractions from lubricant as a function of the lubricant blend, specifically the base oil and base oil viscosity.

Can you explain that?

 

[Overfill]

Can you explain that?

1. I misspoke, reviewing my post today: "specifically the base oil." viscosity should be omitted as its not dependent on that.

2. The solubility and separability of two hydrocarbon components/streams is more than just looking at their independent boiling points. They will possess an interactive characteristics (i.e. MW, polarity, ect) that improve or hinder solubility. Thus every component of the lubricant will affect how strongly it holds or lets go of unburnt fuel fractions, partial decomposition products, water, ect. I feel its important here to reiterate that this does not imply vast blend/lubricant options, nor is this a primary way to mitigate fuel dilution.

3. I'm sorry kschachn, I dont have the quantitative answer for the discussion, no. I would like to, though.

 

[ZeeOSix]

Correct. The 1.2% was baseline for the monograde.

Why so high with only 8 miles on new oil? Was the sample taken after the first drive of 8 miles in cold weather before the sample was taken? Seems pretty odd to end up with 1.2% fuel dilution in a short 8 mile drive unless there was a fueling issue or bad injector(s).

 

[UGASpike]

Why so high with only 8 miles on new oil? Was the sample taken after the first drive of 8 miles in cold weather before the sample was taken? Seems pretty odd to end up with 1.2% fuel dilution in a short 8 mile drive unless there was a fueling issue or bad injector(s).

Would I speculate carry over from the previous drain mixed with a short trip or two over the 8 miles?

 

[ZeeOSix]

Would I speculate carry over from the previous drain mixed with a short trip or two over the 8 miles?

That would take a lot of left over oil to result in a full sump to be at 1.2% fuel dilution. And if not, it would really have to load up the oil with fuel over just an 8 mile drive.

 

[2.7ecoboostFordBronco]

The UOA says the fuel dilution was 1.2% with 8 miles on the oil sample. What?

I take it that samples 3 and 4 are the HPL SAE 40, and sample 3 was the baseline right after changing to the SAE 40.

I’ve had Polaris return a 0.5% GC fuel dilution result on a virgin/baseline sample that they thought was a used sample. It was Valvoline Restore and Protect 5W-30. I’m not sure what to make of that other than “hey it’s a cheap $30 analysis”.

VOA

Reply below mine had a 1.3% GC fuel Valvoline Restore and Protect VOA also. I guess we should only consider the Polaris GC accurate within about 1% with a bias on the high side?

I know SpeeDiagnostix’s vendor Predictive Maintenance also claims to use GC, though “not in the scope of accreditation” usually came back at about 1/3 - 1/2 the fuel dilution of Polaris on samples of the same oil. On the other hand I’ve had Wearcheck GC come in 1/4 higher than Polaris and 4x higher than SpeeDiagnostix.

 

[kschachn]

I’ve had Polaris return a 0.5% GC fuel dilution result on a virgin/baseline sample that they thought was a used sample. It was Valvoline Restore and Protect 5W-30. I’m not sure what to make of that other than “hey it’s a cheap $30 analysis”.

VOA

Reply below mine had a 1.3% GC fuel Valvoline Restore and Protect VOA also. I guess we should only consider the Polaris GC accurate within about 1% with a bias on the high side?

I know SpeeDiagnostix’s vendor Predictive Maintenance also claims to use GC, though “not in the scope of accreditation” usually came back at about 1/3 - 1/2 the fuel dilution of Polaris on samples of the same oil. On the other hand I’ve had Wearcheck GC come in 1/4 higher than Polaris and 4x higher than SpeeDiagnostix.

Which ASTM test was being used? There is more than one utilizing a gas chromatograph and there are different levels of precision. The more precise one is more complicated and costs a lot more to perform.

 

[Hohn]

Polaris agreed to re-run and I just got notification of a new report, yet every value is exactly the same.

I’m being pencil whipped and not at all happy about it. I’ve emailed the customer service rep asking what’s going on and whether I’m going to get a re-run or not.

I hope Polaris comes through, I’d hate to have to find another lab.

 

[2.7ecoboostFordBronco]

Which ASTM test was being used? There is more than one utilizing a gas chromatograph and there are different levels of precision. The more precise one is more complicated and costs a lot more to perform.

Polaris states they use ASTM D7593
Speediagnostix uses ASTM D3525M
Wearcheck uses ASTM D3524

 

[Hohn]

Polaris states they use ASTM D7593
Speediagnostix uses ASTM D3525M
Wearcheck uses ASTM D3524

Supposedly D7593 has the best resolution and repeatability, newest method.

 

[Japanese]

Polaris states they use ASTM D7593
Speediagnostix uses ASTM D3525M
Wearcheck uses ASTM D3524

What about Blackstone Labs?

Even if all of those tests are not precise enough, we already have a few people who saved their engines with early proactive actions based on warnings on their oil analysis. I think most of those people used the Polaris labs.