Rate of flow at low temperatures

[Snagglefoot]

There have been various comments regarding the rate of the flow and the time it takes for oil to travel through the oil passages. Here is a comment from the Shell Rotella website comparing there T6 5W40 Synthetic vs their T4 conventional 15W40.

 

[Imp4]

Originally Posted by Shell
oil flow between the sump and gallery was considerable faster with Shell Rotella....

And.

Originally Posted by Shell
This means that the oil reaches critical engine parts faster.

Thank you Department of Redundancy Department.

 

[CT8]

Who woulda thunk it.

 

[MrMoody]

Low Termperature?

Originally Posted by CT8
Who woulda thunk it.

Yeah, 5W flows better than 15W when cold, what a shocker.

 

[edhackett]

Originally Posted by MrMoody
Low Termperature?

Originally Posted by CT8
Who woulda thunk it.

Yeah, 5W flows better than 15W when cold, what a shocker.


Especially when the 5W is tested at 1C above its certified pumping temperature and the 15W is 11C below its certified pumping temperature. I wonder what the results would have been at -24C.

Ed

 

[madeej11]

Originally Posted by Imp4
Originally Posted by Shell
oil flow between the sump and gallery was considerable faster with Shell Rotella....

And.

Originally Posted by Shell
This means that the oil reaches critical engine parts faster.

Thank you Department of Redundancy Department.

Great sense of humor Imp! Cracked me up.

 

[Leo99]

They went all the way down to -34°C to prove their point?

 

[Revving2Redline]

Lets make it interesting and start the test at -50 at least. Better yet we drive to Yellowknife NWT and begin there and end in Nome,AK.

 

[JLTD]

Where are all the "positive displacement" guys?

🦗🦗

 

[Shannow]

Originally Posted by JLTD
Where are all the "positive displacement" guys?

🦗🦗


Resaerch "MRV". pumpability. SAE J300...anything I've posted in the last 20years...and inform youself on why that advertising is made by the department of redundent information....

Yes, the pumps are PD...yourknowledge continues to be lacking, in spite of a couple of years of the same lacking in fundimental understanding jabs...

 

[alarmguy]

Originally Posted by Leo99
They went all the way down to -34°C to prove their point?


Yeah, that is what I thought, I would like to know flow at 30F NOT (minus) - 30F I would have found that interesting.

Common sense would say that 5w oil will flow a lot faster then 15w at minus 30 degrees F.

 

[kschachn]

Originally Posted by JLTD
Where are all the "positive displacement" guys?

🦗🦗

Are you claiming that the oil pumps on engines aren't positive displacement?

 

[JLTD]

Originally Posted by kschachn
Originally Posted by JLTD
Where are all the "positive displacement" guys?

🦗🦗

Are you claiming that the oil pumps on engines aren't positive displacement?


No.


Originally Posted by Shannow
Originally Posted by JLTD
Where are all the "positive displacement" guys?

🦗🦗


Resaerch "MRV". pumpability. SAE J300...anything I've posted in the last 20years...and inform youself on why that advertising is made by the department of redundent information....

Yes, the pumps are PD...your knowledge continues to be lacking, in spite of a couple of years of the same lacking in fundamental understanding jabs...


No intent to offend or show ignorance here Shannow. Taking a jab in fun as you noted. If I said it in person you would laugh with me due to facial expression and inflection.

I actually was looking for some PD commentary, since apparently Shell has done some testing..... I wish they would publish some data to show how much quicker the 5w circulated rather than making a blanket statement.

My opinion has always been that even though flow may occur at the same rate at the pump that a thinner oil at startup will circulate more freely elsewhere and thus flow a bit quicker in some areas since fluids choose the path of least resistance.

Thanks for the suggestion, I'll look up the J300.

....after some reading, it appears that engine design and oil chemistry have a large effect in oiling times - as expected. Although old data, I found this article and (kidding aside) would value your thoughts.

https://www.jstor.org/stable/44467123?read-now=1&seq=1#metadata_info_tab_contents

Sorry I'm not a scientist in the lubrication field.

 

[ARCOgraphite]

Originally Posted by kschachn
Originally Posted by JLTD
Where are all the "positive displacement" guys?

🦗🦗

Are you claiming that the oil pumps on engines aren't positive displacement?


Not when the pump is bypassed internally - as many are - the result is like a blow off valve; max spec pressure only is present at the filter inlet and that's it.

I don't see why there is such a misunderstanding HERE.

If there exist NO pump bypass, Ill give you that if the oil cant get through the filter, the pressure will blow that canister open blow out the base seal to get there.

Actually, I prefer that engineering approach to engine lubrication:

A Large capacity Filter mounted vertical at sump level, NO ADBV, NO bypass.

May create a problem with FAILSAFE but then solve many other suspected issues Ive experienced the past decade and a 1/2.

 

[toneydoc]

You guys may be forgetting the fact that you all are educated about oil and flow properties, labeling of the oil containers, and temperature effect on oil flow

However there are many other folks in the world who are not so educated, or do not care to learn these facts.

In a really cold environment, maybe that will help a few with their oil selection. If it helps someone out with a better choice, good for them and their engine.

I really do hope it helps somebody. I know it will not be meaningful to you guys.

Take care all

 

[4WD]

More and more are going to variable which not only can lower torque … but allows for flexibility in designing a system.

 

[kschachn]

Originally Posted by ARCOgraphite
Not when the pump is bypassed internally - as many are - the result is like a blow off valve; max spec pressure only is present at the filter inlet and that's it.

I don't see why there is such a misunderstanding HERE.

If there exist NO pump bypass, Ill give you that if the oil cant get through the filter, the pressure will blow that canister open blow out the base seal to get there.

Actually, I prefer that engineering approach to engine lubrication:

A Large capacity Filter mounted vertical at sump level, NO ADBV, NO bypass.

May create a problem with FAILSAFE but then solve many other suspected issues Ive experienced the past decade and a 1/2.


Ii have no idea what you're trying to say. Doesn't a positive displacement pump move the same volume of material regardless of the pressure?

 

[Snagglefoot]

Originally Posted by Shannow
Originally Posted by JLTD
Where are all the "positive displacement" guys?

🦗🦗


Resaerch "MRV". pumpability. SAE J300...anything I've posted in the last 20years...and inform youself on why that advertising is made by the department of redundent information....

Yes, the pumps are PD...yourknowledge continues to be lacking, in spite of a couple of years of the same lacking in fundimental understanding jabs...


Typical Shannow. Starts with an attack. Yes, the pump is positive displacement, but the intake down in the sump is fed by atmospheric pressure and the oil is very thick. Cavitation is occurring. And even if it was not, typical oil pumps have a spring assembly and piston that will dump some oil back into the pan if the pressure gets too high. Where did you get your engineering degree? Honestly.

 

[ARCOgraphite]

Originally Posted by kschachn
Originally Posted by ARCOgraphite
Not when the pump is bypassed internally - as many are - the result is like a blow off valve; max spec pressure only is present at the filter inlet and that's it.

I don't see why there is such a misunderstanding HERE.

If there exist NO pump bypass, Ill give you that if the oil cant get through the filter, the pressure will blow that canister open blow out the base seal to get there.

Actually, I prefer that engineering approach to engine lubrication:

A Large capacity Filter mounted vertical at sump level, NO ADBV, NO bypass.

May create a problem with FAILSAFE but then solve many other suspected issues Ive experienced the past decade and a 1/2.


Ii have no idea what you're trying to say. Doesn't a positive displacement pump move the same volume of material regardless of the pressure?

Yes some this way and some out the back door. So if the front door is blocked, it will go out the back door. And the back door is not into the engine.

Think of a garden hose with a 1" slit in it. When lightly restricted with a spray nozzle, the water will mostly come out the hose end, but put your thumb over the hose end, and the remaining water will spray out of the slit in the hose. Same volume being moved. just some going the "wrong" way.

Again some engines dont have a internal pump bypass or pressure regulator. But I would bet - in small asian engines - many do.

 

[Job]

It's a good topic because there are so many who think thicker oil is better. Thicker can mean more relief valve opening, less flow to the engine, and more stress on the oil pump drive. Maybe this is obvious, but there are recurring posts of people over ruling their owners manual.