Test Idea To Determine If Filters Bypass During Normal Operation

[OffOrWFO]

I had this idea on how to determine how often the bypass in FF filters open during normal operation. If I put oil pressure gauges on the inlet and outlet of a remote mounted full flow it would show the pressure differential across the filter. Compare these pressures to the filters bypass rating and we should be able to make a conclusion. Comparative flow rates could also be used to determine which filters flow better or filter better.
I know the pressure differential tests have been done before but they seem to be kind of inconclusive because of the lack of real engine operating conditions. I could test different filters from 0F to 230F and oil pressures from 30 to 80 psi with the 302 I would use. Different weights could also be run, both SAE and winter. Syn vs dino at low temps would also be interesting. I won't run a 20W in this engine though, I normally run 10w-40. Also this engine has a HVHP oil pump and a oil temp gauge mounted in the pan.

The remote mount would limit the filter choices to the 3/4-16 size threads. Basically the FL-1A and its shorter sized counter part. These bigger filters might not mean much to a lot of you with smaller engines and oil filters but I think it's probably all relative. This engine can pump enough oil to tax even the big filters making it comparable to a small engine and small filters, theoretically.

Do you all think this is test worth doing? Will it give any meaningful data? I was thinking of using two mechanical autometer gauges but I would be open to other more accurate options. Opinions? Suggestions?

[ November 15, 2004, 06:45 PM: Message edited by: OffOrWFO ]

 

[TallPaul]

I think it is a great idea. You maybe could use your existing gauge (if mechanical) for one side of the filter if it's tap into the oil system is not too far from the filter.

I think they are usually downstream of the filter, so one could get a spacer, like one of those oil coolers that loops a water line through a spacer between the filter and block. Just spins on I think. Instead of using it for a cooler you could use it to tap the outer flow area (incoming side) of the spacer (in a thick enough area to hold) for an oil line to mount the gauge line.

One test I did was with my oil pan heater on a 35 degree F day. With the heater on all night, I fired it up and immediately hot oil was in the filter can (hand tested). On another similar night, but the heater not plugged in, I drove several minutes and got out and did not feel hot oil in the filter. Suggests that winter starts are in bypass for a long time. Someone should repeat this test though.

 

[427Z06]

quote:

---

Originally posted by OffOrWFO:
Do you all think this is test worth doing? Will it give any meaningful data?

---

Here's a few thoughts.

Too many restrictions on filter sizes. Many new vehicles are coming equipped with dinky sized filters. Need to find some of these in the 3/4-16 size threads to see if there is something special about the media in these thimble sized filters. Pressure drop across the filter would let you know if you're threading in dangerous territiory.

Using test oil that has very few VII or pour point depressants may make the job easier to calculate viscosities at various temperatures. Maybe something like M1 10w30 would be a good test oil. Send a sample in and get viscosity measured at both 40C and 100C for even more accuracy.

Don't be to surprised if the oil pump in a high winding DOHC V6 actually outflows that which you would find in typical pushrod pig-iron small block.

All filters tested should have a matching unit dissected for documentation purposes.

 

[XS650]

quote:

---

Originally posted by OffOrWFO:

Do you all think this is test worth doing? Will it give any meaningful data? I was thinking of using two mechanical autometer gauges but I would be open to other more accurate options. Opinions? Suggestions?

---

Yes. You should use some gauges with a 270 angular degree readout instead of the cheapos 90 degree readouts.

You could calibrate them to each other by cobbling up some fittings and applying air or water pressure to them to see what the differences are between the two gauges. You will be seeing small pressure differences in many cases, so it's important that you know the relative readings of the guages when they both see the same pressures.

Ideal would be a differential pressure gauge, but that would be expensive unless someone got generous or you found one surplus someplace.

There are also surplus gauges with two needles on on coaxial shafts that read two pressures.

A digital gauge would be easier to read accurately

Digital oil pressure gauge

and you could buy two senders and connect them to the one gauge with a switch.

There is another option. If the standard US type 240-33 ohm electrical pressure senders are reasonably linear, some electronicer should be able to tell you how to make a simple circuit so you can read the differences in them instead of subtracting one reading from the other.


Tallpaul: Even if the filter was in bypass, there should still be oil flowing through the element at whatever presure differential the bypass valve regulates to. I think you didn't feel any warmth on the filter because the oil in your crankcase wasn't warm yet.

 

[cryptokid]

instead of spending hundreds on some stupid oil pressure gauges just get 2 gauges from walmarts automotive section.
they are 9 dollars each and come with all the hardware needed for the install. they are also very accurite, i have used them lots of times and i awalys test them against my digital gauge for accuracy. they are dead on awalys. havent had a bad one yet.

 

[TallPaul]

quote:

---

Originally posted by XS650:

Originally posted by OffOrWFO:
[qb] Tallpaul: Even if the filter was in bypass, there should still be oil flowing through the element at whatever presure differential the bypass valve regulates to. I think you didn't feel any warmth on the filter because the oil in your crankcase wasn't warm yet.

---

Good point. What it better served to show was that the oil wasn't even beginning to get warm after several minutes.

[ November 15, 2004, 09:13 PM: Message edited by: TallPaul ]

 

[kenw]

quote:

---

Originally posted by cryptokid:
instead of spending hundreds on some stupid oil pressure gauges just get 2 gauges from walmarts automotive section.
they are 9 dollars each and come with all the hardware needed for the install. they are also very accurite, i have used them lots of times and i awalys test them against my digital gauge for accuracy. they are dead on awalys. havent had a bad one yet.

---

digital has nothing to do with accuracy.

but i would tend to agree with you suggestion.

 

[leanintoit]

quote:

---

Originally posted by OffOrWFO:
I had this idea on how to determine how often the bypass in FF filters open during normal operation. If I put oil pressure gauges on the inlet and outlet of a remote mounted full flow it would show the pressure differential across the filter. Compare these pressures to the filters bypass rating and we should be able to make a conclusion. Comparative flow rates could also be used to determine which filters flow better or filter better.

---

This will not work. You ever notice how some filters are listed as opening at something like 11-15psi. These bypass valves are not that precise. What do you call open? Is it when it first cracks open to that first drip or is it half it's total travel or is it max open? These valves don't seal completely in the first place. Most all of them leak when closed. They don't go from a closed position at 10psi and wide open at 11psi. The valve is spring actuated and just like a spring as pressure is applied the valve begins to move. More pressure more movement. There is no sudden or discernable pressure change on either the input or output pressure of the filter to compare anything to.

The media always passes oil under pressure even when the bypass is wide open, more pressure = more flow. The media does have a max pressure point at which it will fail and that is what the bypass valve is there to prevent. There is no way to find the opening pressure of the bypass valve with pressure gauges therefore you can't determine which filters flow better or filter better. A filter with no bypass is a different story but those are few and far between and for good reason.

This seems kind of rambling, hopes it makes sense.

 

[Gary Allan]

You're gonna find that, at least after warm up, you're probably not going to come anywhere near the bypass setting to ever challenge the "threshold" or "break over" point (envisioning diodes in avalanch).

but it will be interesting to see the 3/4-16 testing done. That filter in Ford/Mopar comes in all sizes sharing the same gasket size. This filter comes in every size imaginable. The one on my son's NEON is the thimble size filter

51348
UPC Number: 765809513488
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 3.404
Outer Diameter Top: 2.921
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.734 2.430 0.226


Part Number: 51516
UPC Number: 765809515161
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 4.828
Outer Diameter Top: 2.921
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.734 2.430 0.226


Part Number: 51515
UPC Number: 765809515154
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 5.178
Outer Diameter: 3.660
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.834 2.462 0.200

Part Number: 51068
UPC Number: 765809510685
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 4.338
Outer Diameter Top: 3.660
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.834 2.462 0.200

Part Number: 51085
UPC Number: 765809510852
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 3.790
Outer Diameter Top: 3.660
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.834 2.462 0.200

Part Number: 51348
UPC Number: 765809513488
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 3.404
Outer Diameter Top: 2.921
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.734 2.430 0.226

Part Number: 51773
UPC Number: 765809517738
All Applications
Style: Spin-On Lube
Service: Lube
Type: Full Flow
Media: Paper
Height: 6.982
Outer Diameter Top: 3.663
Outer Diameter Bottom: Closed
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes

Gasket Diameters
Number O.D. I.D. Thk.
15244 2.834 2.462 0.200

All of these gaskets should work on the Permacool adapters ..and if size permitted ..they should be able to swap between the various applications.

Does this look diverse enough for the test??

[ November 16, 2004, 01:13 AM: Message edited by: Gary Allan ]

 

[427Z06]

quote:

---

Originally posted by leanintoit:
This will not work. You ever notice how some filters are listed as opening at something like 11-15psi. These bypass valves are not that precise. What do you call open? Is it when it first cracks open to that first drip or is it half it's total travel or is it max open? These valves don't seal completely in the first place. Most all of them leak when closed. They don't go from a closed position at 10psi and wide open at 11psi. The valve is spring actuated and just like a spring as pressure is applied the valve begins to move. More pressure more movement. There is no sudden or discernable pressure change on either the input or output pressure of the filter to compare anything to.

The media always passes oil under pressure even when the bypass is wide open, more pressure = more flow. The media does have a max pressure point at which it will fail and that is what the bypass valve is there to prevent. There is no way to find the opening pressure of the bypass valve with pressure gauges therefore you can't determine which filters flow better or filter better. A filter with no bypass is a different story but those are few and far between and for good reason.

This seems kind of rambling, hopes it makes sense.

---

Well, it won't be as cut and dry as some might think, but I don't think it will be useless either.

Recall that the original intent of the test was to "determine how often the bypass in FF filters open during normal operation", not to determine the best flowing filter. For example, if you have a 8-11 psi bypass-valve and the oil is cold, and if your at idle and you see ~8-11 psi pressure differential across the filter, you can be pretty sure the filter will be in bypass at any RPM off idle. As the oil warms up, you should see less and less of a pressure drop across the filter. You could also run up the rpms at several temperature points to see when the pressure differential levels off at ~8-11 psi. Even if the filter flows enough with cold oil to have substantially less than a ~8-11 psi pressure differential, as you raise the rpms there will most likely be some point where the pressure differential reaches ~8-11 psi and then levels off.

Another point to consider is that the oil pump bypass-valve limits pressure to the entire lubrication system, and even though max pressure will be related to the viscosity of a given oil, and thus temperature, it does so pretty consistently. Ask anyone with an oil pressure gauge.

Another test you could perform is to test identical filters except one would be new, and the other could have ~6-10K miles on it to see how the pressure differential changes as the filter fills with whatever it catches.

 

[427Z06]

quote:

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Originally posted by Gary Allan:
You're gonna find that, at least after warm up, you're probably not going to come anywhere near the bypass setting

---

Yep, but as TallPaul alluded to, how many people are not getting there oil much above 104F if they mainly travel short, low-power output trips in winter? I've observed low oil temps for 20 min or less trips in Austin, in January, so it's gotsta be substantially more difficult to get 180F+ oil temps in Minneapolis in January.

Imagine someone trying to run 15w40 40C 120cSt HDEO in Minneapolis at freezing temps with a PureOne PL10241 on an engine that flows 2gpm/1K rpm. That filter may be in bypass mode most of a 20 minute trip.

 

[Gary Allan]

I guess you're both right (gosh I need my meds changed - stroke maybe

) There is surely some condition where this will occur.

I not convinced that we fully understand the fluid dynamics involved here. As we've discussed on other threads ...somethings do not add up in oil flow or at least only currently dwell in theory. This test, I think, will answer some of those questions.

For example, in Bob's test ..we knew the differential ..but we never knew what the engine guage read at those pressures. We didn't know if we were at idle speed ...terminal peak pressure ..whatever.

So the parts list is one permacool single ford thread filter, one block adapter ...two 1/2" close nipples, two 1/2" T's, two 1/2 x 1/8" bushings, four 1/2" barbed fittings, two lengths of hose, 4 small hose clamps, and two 0-100 pressure gauges. Is there also going to be a temp index in the mix here? That would require one 1/8" T for the temp sender and one 1/8" close nipple... and about 4 or 5 filters of various sizes. Never mind ..you already have a pan temp sender/gauge.

This bill is getting up there in $$ unless someone has most of the stuff just sitting around already. The sad thing is, I just gave away two silicon filled 270° industrial large face pressure gauges that I had no use for (1/4" NPT threads). They wouldn't require any wiring at all and the whole thing could be mounted (like Bob's was). I may have one or two still sitting around (I'll check).

Other than that, I could probably lend some other material support to the test. Some of the fittings I surely have.

Now if OffOrWFO is flush ....I'm sure we would all be very appreciative of his selfless sacrifices for the knowledge to be obtained...and the betterment of BITOG

 

[427Z06]

quote:

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Originally posted by Gary Allan:
Now if OffOrWFO is flush ....I'm sure we would all be very appreciative of his selfless sacrifices for the knowledge to be obtained...and the betterment of BITOG

---

For sure. OffOrWFO would get many:

from me.

 

[doubleshockpower]

So, my daughter brings over her '82 toyota (42k mi.) for an oil change...I go to wal-mart and buy a st filter for a corolla and it fits..but it's the wrong filter because her toyota is really a tercel 1.5... anyway, I've come to learn the wrong filter thats on the car now has a 18lb bypass valve and the correct filter has a 8lb valve.

Do I call her back and switch the filter or let it go 4k?

 

[427Z06]

Is it the identical size filter except for the bypass setting?

 

[doubleshockpower]

no, it has a larger diameter but the seal is fine..no leaks.

 

[427Z06]

According to Wix this is what they spec for a '82 Tercel 1.5L:

Part Number: 51394
Style: Spin-On Lube
Type: Full Flow
Height: 2.977
Outer Diameter Top: 2.685
Thread Size: 3/4-16
By-Pass Valve Setting-PSI: 8-11
Anti-Drain Back Valve: Yes
Gasket Diameters
Number O.D. I.D. Thk.
Attached 2.475 2.173 0.233

And if you go to Purolator and spec a Pure 1 as a cross reference you'd get this:

PL14476
Anti-Drain Back Valve: Yes
Height: 2.93
O.D.: 2.69
Type of Filter: Spin-on
Threads: 3/4-16
Thread Pitch: UNF-2B
Relief Valve P.S.I.: 14-18

But a Purolator speced for that Tercel would be:

Anti-Drain Back Valve: Yes
Height: 3.94
O.D.: 3.15
Type of Filter: Spin-on
Threads: 3/4-16
Thread Pitch: UNF-2B
Relief Valve P.S.I.: 12-15

Hmmm...I usually don't like to vary them by more than a few PSIs but in this case I think you'll be OK. Although, I wouldn't go for an extended OCI.

[ November 17, 2004, 02:05 AM: Message edited by: 427Z06 ]

 

[doubleshockpower]

Hmmm, thanks for the reference..Dog gone trunk said Toyota Corolla Tercel..confusing to a Honda guy...lol.

 

[Ugly3]

Most automotive oil pumps put out between 3 and 5 gallons per minute. Oil filters are rated to have a pressure differential of .3# at 3 gallons per minute flow. It is highly unlikely that the bypass will be in effct during normal driving. Maybe some when the engine is cold but other than that it is almost a moot point.

 

[garyb80]

One way to possibly see how much a filter bypass opens would be to set up a pump and filter mount on a jig, and pump oil that has been "seeded" with some visible contaminant. Pump the contaminated oil into a large glass container and look for visible particles. Anything visible would be more than large enough to be caught by any filter element so it would have gone through the bypass. Do this at various temps or with various viscosities.

Anyone out there with the time and the cash?