FL-500S'...new and old designs...side by side

[ZeeOSix]

Originally Posted By: tig1
Originally Posted By: hatt
Originally Posted By: ZeeOSix

Keep in mind that one filter example doesn't mean every Motorcraft with louvers is going to be made correctly. We've seen louver opening size vary all over the place on the same exact brand & model of oil filters.
It doesn't look like louvers would be that difficult to manufacture. Do they buy whatever thickness and grade sheet steel was on sale that day and run it through the machine?


They use coiled steel and they have parameters they follow.


Apparently their parameters aren't very tight.

 

[Onug]

Got some alone time finally to measure the holes of each design

Old/"hole" design
- holes are 5/32"
- # of holes: 71
- Total Area: 1.36 in-sq

New/Louver design
- Louvers are 0.220"x0.026"
- # of louvers: 310
- Total Area: 1.77 in-sq

So the louver design has about 30% more "open area" for oil to flow. The 0.026" measurement was the thinnest shim I could fit in every (about 10) slot I tested. Many accepted a 0.028", but that's where the tolerances started to kick in. I'm surprised there isn't more area for oil to flow in the new design. Looks can be deceiving I guess, and the holes in the old design are large enough to nearly catch up to the slot count in the louver design.

Of course, this assumes "all other things are considered equal". Obviously the narrower gap of the louver design will become a limiting factor with the viscosity of the oil. It would be interesting if someone could somehow calculate the narrowest slot that oil can flow through before the oil starts to become restricted.

 

[bullwinkle]

Originally Posted By: Joenpb
Originally Posted By: SirTanon
If you ask me, the filter with louvers (assuming they're all, or really even 50%, formed well) should flow a LOT more through the center tube compared to the old style with the holes. It should also flow a lot more uniformly, compared to the relatively limited spacing of the holes in the old style.


A voice of reason.
It's Purolator-QC is not exactly in their game plan. Frightening how much better the Chinese built filters look... (although unknown media quality).

 

[ZeeOSix]

Originally Posted By: Onug
Got some alone time finally to measure the holes of each design

Old/"hole" design
- holes are 5/32"
- # of holes: 71
- Total Area: 1.36 in-sq

New/Louver design
- Louvers are 0.220"x0.026"
- # of louvers: 310
- Total Area: 1.77 in-sq

So the louver design has about 30% more "open area" for oil to flow. The 0.026" measurement was the thinnest shim I could fit in every (about 10) slot I tested. Many accepted a 0.028", but that's where the tolerances started to kick in. I'm surprised there isn't more area for oil to flow in the new design. Looks can be deceiving I guess, and the holes in the old design are large enough to nearly catch up to the slot count in the louver design.


Thanks for taking the time to get this info. Yeah, I would have expected more of a difference in total area. Now imaging if those louvers were only opened up 1/2 or 1/3 of the way, then the total area would be less than the old hole design.

Originally Posted By: Onug
Of course, this assumes "all other things are considered equal". Obviously the narrower gap of the louver design will become a limiting factor with the viscosity of the oil. It would be interesting if someone could somehow calculate the narrowest slot that oil can flow through before the oil starts to become restricted.


Since the oil pump is positive displacement, it will keep forcing oil through the oiling system until the pump hits pressure relief. What very choked down louvers will do is cause a higher delta-p across the filter which will make the filter's bypass valve open up.

So some of these louvered center tubes that are severely closed could be causing the filter to run in bypass most of the time. Not something I'd want going on in my vehicle.

 

[Onug]

An interesting thought...the louver design has openings in both directions, but when you stare into the tube (of an assembled filter), you can only really judge the openings that are facing up. So right out of the gate you're only able to assess 50% of the louver cuts. But since you can't see all of the louvers, you're probably making a judgement call on maybe 25-30% of the total cuts.

Honestly, I really wanted to be a "pro-louver" voice here. I'm not "anti-louver" by any means, but with only about a 30% difference, there isn't a lot of "cushion" if a section of the louvers are poorly formed or damaged during mfg.

Question - I've seen one picture floating around of bad louvers. Are there quite a few here on the forum to review? Curious if we have a decent sample size of problem cuts

 

[hatt]

Originally Posted By: ZeeOSix
Originally Posted By: tig1
Originally Posted By: hatt
Originally Posted By: ZeeOSix

Keep in mind that one filter example doesn't mean every Motorcraft with louvers is going to be made correctly. We've seen louver opening size vary all over the place on the same exact brand & model of oil filters.
It doesn't look like louvers would be that difficult to manufacture. Do they buy whatever thickness and grade sheet steel was on sale that day and run it through the machine?


They use coiled steel and they have parameters they follow.


Apparently their parameters aren't very tight.

Maybe it's the Monday morning crew's fault. Really, it seems that forming louvers in sheet metal would be the easiest part of making a filter.

 

[CR94]

1.36 in² is a lot larger than the opening through which the oil exits the filter---not to mention the restriction of bearings etc. farther downstream. So that's all much ado about nothing, except in cases of louvers that aren't properly opened.