Union Sangyo oil filters

[Geoff's 240z]

Thought I was buying a Nissan filter when ordering from Motorsport Auto because they look just like the OEM product with color and characters. Any thoughts on quality of these filters? Also, any thoughts on why the idea of not seeing a Nissan filter under the hood bothers me? Thanks! 

[heyitsrama]

We will need to do some shock therapy to figure out why it bothers you.

https://bobistheoilguy.com/forums/threads/union-sangyo-oil-filters.286421/

some people compare them to denso. 
 

ive been using bosche ones from https://www.rockauto.com/en/catalog/nissan,1973,240z,2.4l+l6,1209170,engine,oil+filter,5340

 

[psdenno]

1 hour ago, Geoff's 240z said:

 Also, any thoughts on why the idea of not seeing a Nissan filter under the hood bothers me? Thanks! 

Adjustment Disorder.

https://www.webmd.com/mental-health/mental-health-adjustment-disorder

We can help you work through this.  Fortunately, I'm married to a psychologist so I no longer care what kind of oil filters are on my cars.

Edited June 3, 2021 by psdenno

[Zed Head]

Here's the guts.

 

[Geoff's 240z]

Is that good or bad?

[ETI4K]

Yikes, not really sure what was. 

Besides oil wars, folks are having filter wars.  My concern with filters lies mainly with the fact they bypass oil directly to the motor whenever the static+dynamic pressure exceeds a threshold - usually when it's quite cold and oil viscosityis at its greatest.  Unfortunately,  the vid didn't provide anything quantitative to consider.  The reason I am focused there is my motor suffered some fair damage from debris that I believe bypassed the filter.

Sorry, don't mean to hijack your thread, just thought I'd offer up what I  am learning and what there is yet to be learnt 😁

The more you look into something,  the less certain and more confused you become.

I'm thinking our motors need two filters.  The normal OEM style filter, and a second filter for bypassed oil.  If nothing else, one that filters out rocks and birds 😉

 

 

[Captain Obvious]

3 hours ago, ETI4K said:

My concern with filters lies mainly with the fact they bypass oil directly to the motor whenever the static+dynamic pressure exceeds a threshold - usually when it's quite cold and oil viscosity is at its greatest. 

The reason I am focused there is my motor suffered some fair damage from debris that I believe bypassed the filter.

I'm thinking our motors need two filters.  The normal OEM style filter, and a second filter for bypassed oil. 

I disagree with both your premise(s) and your conclusion(s).

How far from the original thread do we want to go? Haha!

[ETI4K]

On 6/5/2021 at 10:32 PM, Captain Obvious said:

I disagree with both your premise(s) and your conclusion(s).

Always good to learn. Please explain.

[Captain Obvious]

Well first of all, let me be clear that I'm no lubrication expert, but now that I've got a couple more minutes, let me try to explain a little bit.

First of all, I think the premise that both the static and dynamic pressure are involved is incorrect. Since the bypass valve is around just the filter media, the static pressure should have no effect at all. The only pressure that should matter is the differential pressure across the filter media. Any static pressure should come out immediately in the math.

Second, I would claim that the differential pressure across the filter media (assuming that media is clean) is not high enough to open the bypass valve.

You might say "But what about a cold engine just started then... The cold thick oil would be harder to push through the filter media thereby creating a higher differential pressure across that media". 

And to that, I would say "Yes, but don't forget that cold thick oil would also be harder to push through all the bearing clearances and oil passageways, which would increase the pressure on the clean (outlet) side of the filter, thereby keeping the differential about the same."

As evidence, I would cite the oil pressure gauge. It's on the outlet clean of the oil filter. It's higher when the engine is cold and the oil is thick. And the higher the outlet side, the lower the differential pressure across the media.

And on the inlet side... the pressure into the filter is limited at the top end by the pressure relief valve inside the oil pump.

That's my non-expert take.

[Zed Head]

So, as the engine wears the differential grows geater and the odds of a bypass event increase.  But the clearances are greater so the crud will probably just slip through.

[Captain Obvious]

Hmmm. Never thought about it that way, but I guess that would be true. If you push 60 psi oil into the filter and let the other side hang open into a bucket, the bypass valve will absolutely open because the differential would be so high. So if you put a brand new high pressure oil pump on your tired worn out motor...

The question is... "How much oil volume passes through the filter (per unit of time), and how much pressure does it take to achieve that?"

Or turning the question around... "How much oil volume can you push through while keeping the bypass valve closed?"

Fram's PH8A says the bypass valve opens at 12psi differential. How much oil could you push through the filter at 11 psi differential? Enough for even a worn out motor?

Anyone know what the spec is on the pressed-into-the-block bypass valve is? For all I know, it's lower than the ones built into the filters? I took a quick look at at couple FSMs and didn't find any spec. They talked about it, but no pressure spec.

[ETI4K]

So, I guess this is where things get interesting.  First, my focus is on the first few moments after startup - not when the motor is in some state of 'equilibrium'.  During that time, I am assuming an oil filter is not full of oil and there is not enough oil residing in all the passages, etc. to be able to impart any real resistance to flow.  Before the engine is started, the differential across the filter media is zero.  As oil begins to flow into the filter, its velocity will impart a force on the bypass valve - albeit quite small I'm sure, but important to at least consider since static and velocity pressures are additive.  As the filter approaches being full, oil will begin to be forced through the media raising the static pressure from zero on the oil entering side of the media.  During those first few moments, the rest of the oil system has not yet filled and offers less resistance to flow than it will after oil has been fully distributed to the motor.  This is all qualitative I know, but bear with me for conversation purposes.  The differential pressure across the media is likely higher in these moments than it would be after the rest of the system is pressurized.  If that differential exceeds the filter's bypass valve cracking pressure, a bypass event will occur.

So, without a pump curve, knowing the flow characteristics of the filter media, knowing the actual behavior of the bypass valve (it is most certainly not a precision device), knowing the engine cranking and idling rpms, etc., there'd likely be a fair amount of guessing as to the extent and duration, and therefore significance of a potential bypass event.  That said, this is an interesting read. 

https://www.machinerylubrication.com/Read/29026/engine-bypass-filtration