Extreme Cold ... and oil filters.

[geeman789]

It was - 22f ( -30c ) this morning. Nice. Our Mazda 2 started after being outside, unplugged over night. Not super happy about it, but all good. Car runs M1 0W30 in the winter, with a Fram Ultra filter.

How much actual filtering is taking place at these temps ? Even the 0W is noticeably thicker at these temps. I can't visualize the oil being pumped through the filter element at these temps ... is the filter in by-pass for the first 15 minutes or more ?

What happens when a truck guy just leaves conventional 15w40 in for the winter ... and it gets this cold ? Assuming the truck even starts ...

 

[StevieC]

You would need to know the oil pressure and the bypass oil pressure for your filter to answer that question. Most likely it's in bypass until the oil warms enough to allow the bypass system to close because the pressure has decreased below its threshold.

The 15w40 application will be in bypass just the same until the oil warms enough to lower the pressure enough.

Unfiltered oil is better than no oil.

 

[CharBaby]

IDK if I am saying this quite right but, yes the filter goes into bypass mode until the oil warms enough for proper lubrication and by filter pressure/psi design...

 

[ragtoplvr]

with thick oil the flow volume is reduced a lot too. So the filter does far fewer gallons per minute.

Considering 0W30 you are probably filtering most if not all of the oil.

Rod

 

[StevieC]

Originally Posted by ragtoplvr
with thick oil the flow volume is reduced a lot too. So the filter does far fewer gallons per minute.

Considering 0W30 you are probably filtering most if not all of the oil.

Rod

Really? That's not how I understood it. (filtering because of lower oil flow) That's interesting...

 

[Job]

Originally Posted by ragtoplvr
with thick oil the flow volume is reduced a lot too. So the filter does far fewer gallons per minute.

Considering 0W30 you are probably filtering most if not all of the oil.

Rod


Please explain how that works, assuming the oil pump relief valve is not opened.

 

[Linctex]

Originally Posted by geeman789
... is the filter in by-pass for the first 15 minutes or more ?


No, not at all.

The filter ALWAYS flows, even if just a portion of the oil is going through bypass.

I would say that within a couple minutes, the bypass valve is completely closed with 100% filter flow.

 

[ZeeOSix]

Originally Posted by ragtoplvr
with thick oil the flow volume is reduced a lot too. So the filter does far fewer gallons per minute.

Considering 0W30 you are probably filtering most if not all of the oil.

Rod


Only if the PD oil pump's pressure relief valve is opening. This is why an engine should never be driven off and revved much up on super cold days until the engine warms up some.

I'd say there isn't really much bypassing going on with a 0W oil in this case, as long as the engine is allowed to just idle until the oil gets warmed up some before driving off.

 

[ragtoplvr]

You have 2 bypasses. One is on the pump, it is usually always bypassing some oil. The other is on the filter to prevent the media from rupturing.

If the pump bypass sticks closed, you can actually blow the oil filter off the car.

If the filter bypass sticks closed you can collapse the inner tube and rupture the media.

When the engine is cold there is a lot of pressure loss from the passages and bearing flow is reduced.

It is and always been fact there is less flow with cold, very viscous oil even thought the pump is positive displacement.

Rod

 

[philipp10]

Originally Posted by geeman789
It was - 22f ( -30c ) this morning. Nice. Our Mazda 2 started after being outside, unplugged over night. Not super happy about it, but all good. Car runs M1 0W30 in the winter, with a Fram Ultra filter.

How much actual filtering is taking place at these temps ? Even the 0W is noticeably thicker at these temps. I can't visualize the oil being pumped through the filter element at these temps ... is the filter in by-pass for the first 15 minutes or more ?

What happens when a truck guy just leaves conventional 15w40 in for the winter ... and it gets this cold ? Assuming the truck even starts ...


look at it this way. So what if for 10 minutes on a freezing morning, the oil is not filtered. It doesn't need to be filtered every pass it makes through the oil pump. If the car was last driven warm, the oil is plenty clean and fine.

 

[ZeeOSix]

Originally Posted by ragtoplvr
You have 2 bypasses. One is on the pump, it is usually always bypassing some oil. The other is on the filter to prevent the media from rupturing.

When the engine is cold there is a lot of pressure loss from the passages and bearing flow is reduced.

It is and always been fact there is less flow with cold, very viscous oil even thought the pump is positive displacement.


On the Z06 the only time I could get the pump to hit pressure relief was revving the engine above ~5000 RPM before the oil was only about half way warmed up. Once the oil was warm, even at redline I didn't detect any oil pump pressure relief. Of course not all oil pumps are designed the same, and it's possible some may really put out a bunch of volume which would cause them to hit pressure relief easier with very cold thick oil.

If the oil is cold, and the pump does not hit pressure relief then all the output volume is still going through the engine regardless if the bearings are flowing the same or not. The extra oil that would have went through the bearings if warmer just gets dumped into the valve train or other areas where there's not a big restriction like journal bearings create. Only time the total oil flow going into the oiling system is cut back is when the pump's pressure relief valve starts opening.

 

[benjy]

for brutally cold temps a REAL group IV + or group V is best as it thickens less from the cold spec oils are tested at.

 

[Pinoak]

Originally Posted by geeman789
It was - 22f ( -30c ) this morning. Nice. Our Mazda 2 started after being outside, unplugged over night. Not super happy about it, but all good. Car runs M1 0W30 in the winter, with a Fram Ultra filter.

How much actual filtering is taking place at these temps ? Even the 0W is noticeably thicker at these temps. I can't visualize the oil being pumped through the filter element at these temps ... is the filter in by-pass for the first 15 minutes or more ?

What happens when a truck guy just leaves conventional 15w40 in for the winter ... and it gets this cold ? Assuming the truck even starts ...


The filter is definitely in by [censored] mode for a bit at those cold starts. It's also probably bypassing when the gas is punched as well.
That's why I think the thread end bypass design is better. Not all particles stick to the surface or get imbeded in the media so it's getting back through the filter at bypass

 

[Linctex]

Originally Posted by Pinoak

That's why I think the thread end bypass design is better. Not all particles stick to the surface or get imbeded in the media so it's getting back through the filter at bypass


Only in "theory"

I have YET to see any "evidence" that this "washing debris from the dome end back into the engine" ever actually occurs.

Honestly..... I seriously doubt it happens. I very seriously doubt it.

 

[Pinoak]

Originally Posted by Linctex
Originally Posted by Pinoak

That's why I think the thread end bypass design is better. Not all particles stick to the surface or get imbeded in the media so it's getting back through the filter at bypass


Only in "theory"

I have YET to see any "evidence" that this "washing debris from the dome end back into the engine" ever actually occurs.

Honestly..... I seriously doubt it happens. I very seriously doubt it.


Evidence isn't always possible. Somtimes we just gotta be able to reason simple things out for ourselves. It's not always necessary to have a video or technical paper or some so called authority on a particular matter to declare something to us.
God gave us brains to think for ourselves and the concept mentioned above isn't complicated in anyway.

 

[Linctex]

Originally Posted by Pinoak
Originally Posted by Linctex
Originally Posted by Pinoak

That's why I think the thread end bypass design is better. Not all particles stick to the surface or get imbeded in the media so it's getting back through the filter at bypass
Only in "theory"
I have YET to see any "evidence" that this "washing debris from the dome end back into the engine" ever actually occurs.
Honestly..... I seriously doubt it happens. I very seriously doubt it.


Evidence isn't always possible. Somtimes we just gotta be able to reason simple things out for ourselves. It's not always necessary to have a video or technical paper or some so called authority on a particular matter to declare something to us.
God gave us brains to think for ourselves and the concept mentioned above isn't complicated in anyway.


REGARDLESS...... dome-end bypass valves do not ruin engines.

It is a fear that is unwarranted...... no reason for it.

 

[Pinoak]

Originally Posted by Linctex
Originally Posted by Pinoak
Originally Posted by Linctex
Originally Posted by Pinoak

That's why I think the thread end bypass design is better. Not all particles stick to the surface or get imbeded in the media so it's getting back through the filter at bypass
Only in "theory"
I have YET to see any "evidence" that this "washing debris from the dome end back into the engine" ever actually occurs.
Honestly..... I seriously doubt it happens. I very seriously doubt it.


Evidence isn't always possible. Somtimes we just gotta be able to reason simple things out for ourselves. It's not always necessary to have a video or technical paper or some so called authority on a particular matter to declare something to us.
God gave us brains to think for ourselves and the concept mentioned above isn't complicated in anyway.


REGARDLESS...... dome-end bypass valves do not ruin engines.

It is a fear that is unwarranted...... no reason for it.


I don't think dome end bypass filters ruin engines. I just think thread end bypass is a better design.

 

[CR94]

Originally Posted by Pinoak
... I just think thread end bypass is a better design.
I just think it's almost always a worse design whenever it results in reduced media area, regardless of the mainly imaginary hazards you guys like to argue about. Among several other drawbacks, reduced area increases the risk and volume of any bypass event, other things being equal.

 

[Pinoak]

Originally Posted by CR94
Originally Posted by Pinoak
... I just think thread end bypass is a better design.
I just think it's almost always a worse design whenever it results in reduced media area, regardless of the mainly imaginary hazards you guys like to argue about. Among several other drawbacks, reduced area increases the risk and volume of any bypass event, other things being equal.

You guys?...hmm lol. Where's my possy at to back me up.
Maybe just maintain a vehicle regularly and I bet you won't be having many overloaded filters. I'll not worry about the smaller media surface so much.

 

[andrewp1998]

thick at -22f?. I thought most
0 w oils flow till -50f?