Where does it go?

Grumpy Bear · April 15, 2019

Where does it go? (Oil)

Southwest Research Institute. (SwRI) and Slone Automotive Laboratory MIT & the SAE publish regularly and publicly. I’ve spent the last week or so reviewing literally hundreds of pages of documents. Why? Because I’ve been reminded that I’m old, and my 90 year old father is outdated and useless. Yea….not so much. Because I’ve been out of the field long enough that it seemed prudent to see what the kids have learned and can teach old dogs.

What I learned was that people (children) seeking a Doctorate sooner or later have to “put their money where their mouth is” and prove that those that preceded them whose knowledge they built their education on were no longer relevant and those works dated past their usefulness. Guess what?

Ecclesiastes 1:9 New International Version (NIV)

What has been will be again,
what has been done will be done again;
there is nothing new under the sun.

There are ignorant beliefs that are and were always wrong, like the earth resting on the back of an elephant and then there is factual knowledge such as the way rings in a cylinder work that are timeless.

In an exceedingly interesting paper published by MIT (Sloan) I was reminded, not learned, that 75% to 95% of oil consumption in an otherwise sound engine is the result of vaporization.

This window is wide because a motors operating conditions are wide, thus engine speed and load swing this number yes but the number that swings it the most is oil film temperature between the rings and cylinder wall. Not blow-by.

Motors use more oil under heavy loads at high rpm and still 75% minimum of oil consumption comes from vaporization. A trace from valve guides. Five to twenty-ish percent from actual blow by. Again load based. As little at 5% blow-by!

What has changed in the 75 plus years since my father’s 1928 Ford Model A isn’t how rings work but advancements in technology in materials, geometry, fit and finish, oil volatility, power density and a half dozen or so other things than have increased effectiveness but not purpose nor methods.

In essence the thing that has changed between 1854, when they were invented, and now is the degree of efficiency in doing their job.

Put on the thinking caps. If 75/95% of a quart in a thousand is vaporization where did that oil go? In your catch can? No not in your catch can. Into your combustion chamber and not via the PCV system. Vaporization happens above the top ring.

NOACK matters. What temperature is the NOACK percentage based on? 250 C! What is the oil temperature of the fluid in that 10 um space between the ring and wall? MIT says it is the average of the ring land temperature and the cylinder wall temperature. Yep the simple average. So here’s a piece of information you can laugh at.

The contribution of ring land temperature alone can be below the NOACK test point with some ease in a moderately loaded gasoline motor.

Simply that means if loads are kept light even a high NOACK oil won’t flash off appreciably and usage near nil.

A 90 year old man’s experience is still more valuable than a forum full of “Back of the oil” can educated ‘thumbs up’ consumers and tin type bloggers.

Edited April 15, 2019 by Grumpy Bear
Spacing.

Grumpy Bear · April 18, 2019

Read a Doctoral dissertation last night from youngster at Winsor University on the subject of piston under crown oil spray and it's effect on piston temperatures. The initial unsprayed temperatures agreed quite nicely with the MIT studies. Chapter 7 conclusions pointed to a 10% to 25% reduction in sensible heat. The hotter the portion of the piston being cooled the greater the impact of the cooling. Something I had not fully considered when I posted the above. Plugging those numbers into the heat balance equation and ring land oil temperatures, under sensible loads, are lower than the HTHS numbers and well below the NOACK levels.

US military 1940 first used this method on WW II air cooled radial motors. Tom Sifton, and I've used allot of this guys equipment, was the first to use in on the ground in post war Harley 750 flathead flat track motors to STOP piston seizures. Pretty common these days. And once again....:

Ecclesiastes 1:9 New International Version (NIV)

What has been will be again,
what has been done will be done again;
there is nothing new under the sun.

Hey, old guys and old school are useless, right?

Paintor · April 18, 2019

Think ya forgot to factor in 4 cylinders shutting down via contracting hydraulic lifters leaving valves closed and 4 cylinders going WHOP WHOP WHOP compressing air with no where to go and the resulting crank case pressure shoving the vaporized oil out the PCV valve cover breather hoses into the intake.

Yeah, long sentence. Sorry.

Switching off 4 cylinder mode and you don’t need a catch can.

Now theorize why it became a National Defense policy to push GM to build an engine with 11 to 1 compression and direct injection. It wasn’t to run on unleaded. Days of oil are about over. Its to run on Ethanol.

Its why GM has to use synthetic oil made from Gas Fracking wells in Pennsylvania and elsewhere around the country.

Saudi is more of our Frienemy...than a Friend. When they told Obama they weren’t accepting US dollars for oil anymore...that man bowed before a King for you. Trumps pushing a fine line of the military being charged with war crimes as Obama did for you.

Iran placing our military on a “terrorist list” means they and Russia-China won’t follow the Geneva Convention on our troops....

It all went to pot when we became bankrupt and ran out of enough oil and gold to function.

The Zero weight oil that vaporizes easily is sprayed under the pistons now so it can also run on 87 octane Unleaded gasoline with 11 to 1 compression. You go back 30 years and tell a mechanic you want an 11 to 1 compression engine to burn the cheapest 87 octane you can find...his words would not have been kind to you. “knock knock knock”

Only reason they now squirt oil under the pistons, reduce knock via reducing temperature. (with a whole lotta timing electrical wizardry)

Edited April 18, 2019 by Paintor

Paintor · April 18, 2019

Henry Ford was right.

He envisioned America running its cars on Ethanol...but wrong on it being from the Potato.

Grumpy Bear · April 18, 2019

Cylinder deactivation has been around since???? The late 1800's to be exact and produced for nearly 50 years. Hit and Miss motors. Some are still in use today and some were as powerful at 100 hp. Yea, more powerful than the F head Fords of the day.

Paintor · April 19, 2019

LoL..yer not as old as I thought.

A Hit and Miss motor has NO CRANKCASE. NO OIL PAN. NO OILING SYSTEM...what so ever. Just grease and a handle you turn to push down more grease on tha spinning parts.

Edited April 19, 2019 by Paintor

Grumpy Bear · April 21, 2019

All one has when they believe AFM is the CAUSE of oil usage is a belief. IMHO. I haven't seen a case study yet that supports this belief. But I'd be interested to see it if it exist. Point me to it! Conjecture and/or anecdotal evidence really doesn't work for me. Well, past the point that I like a good yarn as much as the next guy.

Not really a poly-ticks guy either. More of a science and math guy.

Paintor · April 25, 2019

I think you and I should sue GM to get the Pontiac name for a $1....and release a car that would make Richard Petty proud.

Its these late hours and whiskey that I feel the love...for America..

you in Grumpy?

Grumpy Bear · April 26, 2019

Like I said Paintor, I'm not a poly=ticks sort of guy but....I do like a good Whiskey.

Grumpy Bear · May 8, 2019

It might also go in the recycle barrel.

I consider oil allot. Like a dog with a bone. It does so much and we tend to focus so narrowly. What does it do?

1.) Friction Reduction, it makes things slippery.

2.) Wear Protection. Keeps things apart.

3.) Cooling, Pulls heat from the device.

4.) Corrosion Protection from chemical attack.

5.) Cleans.

Points 1 & 2 have been covered ad-nauseam.

Point #4 is part of the lubrication additive package and an oils polar nature that is seldom an issue under normal operations and maintenance intervals.

Ever wear out a pair of boots? Everyone will have what they consider worn out based on how well they like their boots and of course vanity.

Point’s # 3 & 5 have a large bearing on whatever your definition of a worn out lubricant is.

Point # 3, heat, is often argued from ONLY from the point, will the oil ‘take it’ and still provide adequate film strength thus protection. Fresh undamaged oil is only considered in these winded debates.

The change interval debate is on the length of interval and not the need. That determined by whatever markers the operator is willing to accept as worn out oil. The obvious answer is when it no longer is protecting the device it lubricates.

Problem with that answer is, it is only obvious AFTER THE FACT.

So…common sense says something shorter than a failed motor might be wise and so we rely on common sense. Common sense however isn’t common, isn’t well used AND is a product of personal experiences base on personal and situation uses.

That last paragraph is about 90% true. There are indeed some hard markers that say stick it with a fork…it’s done.

The sentence last in that paragraph, “a product of personal experiences base on personal and situational uses”, is the largest variable in the litter.

Distilled. Worn out is:

1.) Contaminated

2.) Physical alteration

3.) Additive depletion.

Didn’t say anything new there did I? Hum.

Contamination comes in two forms. 1.) Things you can 2.) And thing you cannot filter out. The second is unusual. Like a coolant leak perhaps. Some oil jockey putting ATF in the crankcase. The first is a matter of degree. New oil is dirty if you have it analyzed. Dirty enough to cause wear.

Add depletion is a funny thing. Additives are used up in various ways. Some are secondary. That is an additive is depleted by situation X which is accelerated by condition Y. Acid formation for example requires water and an acidic byproduct such as carboxylic acid formed from thermal degradation. Control heat, control thermal oxidation, control acid formation, control acid neutral chemical depletion. Control load and heat control EP additive depletion. Control water and sulfur control corrosion inhibitor depletion, and so on.

Physical alteration comes in many forms. As above, thermal oxidation. Free radical oxidation. Dilution. Shear thinning and a few more.

What do they all have in common?

STRESS, HEAT and CLEANLINESS.

If you wish to enhance wear protection you have to protect what is protecting your motor, transmission, differential and so on.

The more you want to stress the oil the better the oil needs to be, more robust the add package, the cleaner and cooler the oil must be. Or you can control all three and have it live a very long time.

Paintor · May 9, 2019

#6. Now they use Zero weight oil as a hydraulic fluid to collapse lifters via computer solenoid in milliseconds for a V-8 to switch to V-4 mode.

Lubrication was thrown out the window Grumpy.

Grumpy Bear · May 9, 2019

11 hours ago, Paintor said:

#6. Now they use Zero weight oil as a hydraulic fluid to collapse lifters via computer solenoid in milliseconds for a V-8 to switch to V-4 mode.

Lubrication was thrown out the window Grumpy.

So was accurate knowledge and common sense Paintor but that doesn't mean I'm jumping with the rest of the Lemmings.

Paintor · May 11, 2019

On 5/9/2019 at 11:58 AM, Grumpy Bear said:

So was accurate knowledge and common sense Paintor but that doesn't mean I'm jumping with the rest of the Lemmings.

You didn’t know GM mandated oil go to Zero weight strictly for the V-4 (AFM) hydraulic circuit didja?

You thought it was for..........???

Grumpy Bear · May 11, 2019

2 hours ago, Paintor said:

You didn’t know GM mandated oil go to Zero weight strictly for the V-4 (AFM) hydraulic circuit didja?

You thought it was for..........???

I know my AFM uses 5W30 by the book, no Zero anything and works fine on 10W30 as well. I prefer 0W20 for the fuel savings. Poly-ticks isn't part of the mechanicals equation. So what I KNOW it is for is CAFE. Asia has used zero grade bases for decades now without AFM. All my Honda's are zero base. Now their moving to 0W16.

Once again it isn't zero WEIGHT it is zero GRADE. 0 is not the viscosity cSt or Poise. It is an SAE classification that says a minimum of 3.8 cSt at 100C and no more than 60,000 poise at -40 C. That's the base. Polymerics are added to prevent the viscosity from falling below 9.3 cSt for 0W30 or 5.6 cSt for 0W20. Same as a straight 30 or 20 GRADE. So if you follow that; the purpose of the zero GRADE is pour point suppression. The lions share of fuel savings from a ZERO GRADE base comes from the warm up, not from the running hours.