Ford Bypass Valve - Do Mobil 1 / K&N cause damage?

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The Motorcraft 820S has the Bypass valve on the threaded end of the filter. That's where Ford wants it and it's set to the correct psi according to their specs. Mobil 1 and K&N filters have the valve located in the dome end (as does almost everyone but wix)and possibly doesn't have the exact psi setting Ford mandates.

I want to run the 820S. I am more than sold on it. That is not the question I have.
Since so many synthetic oil change specials include either the Mobil 1 or K&N filter I'd like to be able to take advantage of the deals. Instead of using them as high end paperweights.

Is the Bypass valve location and psi setting, of these filters, potentially damaging to a Ford Modular 4.6?

Looking at a 1 year 12,000 mile interval.
 
Art, as I understand it, Ford's reasoning for placing the bypass valve in the threaded end is to prevent crankcase oil from washing over the dirty side of the filter when it goes into bypass, such as during a cold start. However, there are many thousands (millions?) of mod motors out there that have been run on every filter known to man (yes, even the Orange Can of Doom) and have lasted for many hundreds of thousands of miles, so it can't be THAT big a deal, but I have to figure that Ford knows more about this subject than I do, therefor I use the FL820S exclusively. I mean, it's $3.68 at Wally's, for gosh sakes...why should I use anything else?
 
I think Gary Allan likely can be more precise in the answer but here's my take, based on reading his posts on the subject. Ford tends to be rather 'anal' (his word) regarding the placement of the bypass valve. The idea being to keep dirty oil from washing across the the intake side of the filter and loading the filter, when in bypass.

Based on his thoughts it's not that big a deal(my words). I doubt seriously you would do damage to the 4.6L engine using an M1 or K&N to the OCI you mentioned. Both high line filters that can handle the job. Use those babies. As the previous poster pointed out, many have run on much less with no issues.

All that said, as I'm sure you're aware, the Motorcraft 820S is a lot of bang for the buck.

Hope I gave enough credit to GA, as I wouldn't want to be accused of plagiarism.
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Art,
The M1 filters have worked well for me. I've used them for years, never had any start up noise and my oil stays very clean for my 10,000 mile OCI.
 
Thanks guys. I appreciate the information. I have a Mobil 1 filter on the car right now. I got a vicious start up noise the first week I changed the oil last winter. The temperature was about 20F when this occurred. Naturally I blamed the Mobil 1 filter, since there are lots of complaints, about start up noise, on the Modulars that are not running an 820S. Now I'm wondering if it might just have been the GC, causing the noise, since it is quite a bit thicker than the 5w-20 it replaced? I suppose it is possible.

Could be that the dangerous part of not using the 820S may lie only in the extreme cold?

I get no noise at all at normal temperatures. I never heard another thing from it so I left it in service.
 
Quote:
Hope I gave enough credit to GA, as I wouldn't want to be accused of plagiarism.
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Go ahead .. I don't mind.
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The idea is that there can be silt in the filter. If it's vertically mounted, it would end up at the dome end. When the bypass valve opened, it could push the silt into the center well. OTOH, it may just sit there and ..well, just sit there
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..but the last time I saw any silt in a filter (horizontal mount) was when I used VSOT and it left a moly slug in my filter ..and in my pan, I assume.


..but there's nothing inherently unique about Ford engines over the span of Ford Engine Divisions adherence to this policy in the OEM assembly line and OEM aftermarket filters.

For me, it's sorta like that racer technique on SBC's where they plug the bypass valve in the block. Ford and Mopars can't do that ..but I doubt that they suffer any in terms of wear/refresh rates because of it. Nor do I see either as a performance advantage. It's just what they do.
 
Art,
Wow, I've never had start up noise with my 4.6. I even use the 10-30 wt oil and here in Illinois we get temps down to -10 F and still no noise. Don't know what to think.
 
Originally Posted By: Gary Allan
Quote:
Hope I gave enough credit to GA, as I wouldn't want to be accused of plagiarism.
grin2.gif




LOL.gif
Go ahead .. I don't mind.
LOL.gif


The idea is that there can be silt in the filter. If it's vertically mounted, it would end up at the dome end. When the bypass valve opened, it could push the silt into the center well. OTOH, it may just sit there and ..well, just sit there
21.gif


..but the last time I saw any silt in a filter (horizontal mount) was when I used VSOT and it left a moly slug in my filter ..and in my pan, I assume.


..but there's nothing inherently unique about Ford engines over the span of Ford Engine Divisions adherence to this policy in the OEM assembly line and OEM aftermarket filters.

For me, it's sorta like that racer technique on SBC's where they plug the bypass valve in the block. Ford and Mopars can't do that ..but I doubt that they suffer any in terms of wear/refresh rates because of it. Nor do I see either as a performance advantage. It's just what they do.


The filter on the 4.6 is mounted horizontaly.
 
Which would make me worry about it all that much less. Anything that's able to settle will settle at the lower side of the can. The flow will be 360° toward the dome end bypass.

Anyone find any leftovers in a FL820S?
 
Since you mention it, my sons 4.6L did have a brief rattle at start up using a non Motorcraft filter he had installed at one change. I would describe it as irritating.

I like your two theories, especially temp., as to what the main contributors may have been.
 
Originally Posted By: tig1
Art,
Wow, I've never had start up noise with my 4.6. I even use the 10-30 wt oil and here in Illinois we get temps down to -10 F and still no noise. Don't know what to think.


I don't know either. I'd say GC, and the 10W-30 you use are comparable enough, so that we'd get the same behavior, at the same temperature, using the same Mobil 1 filter. Maybe this particular filter is slightly out of spec. Or maybe when it is new, it's more likely to react this way in the cold? Either way the start up noise lasted just a moment. It was similar to the sound two pieces of metal, struck against each other, would make without any lubrication. Not the kind of sound you ever want to hear if you love your car.
On the other hand, the rapid start up that 5w-20 gave me was lost with the GC. Talk about a difference. Perhaps the extra cranking time allowed for the noise to manifest itself? Who knows? I'm not an oil or filter technologist. Just a chronic observationalist looking for closure.
 
Now that I think about it a dry start is an exact match for the sound at start up I got in the cold.

Is there anything different about a Mobil 1/K&N filter(opposed to the 820S) that can cause a dry start condition on a Ford Modular?
 
Originally Posted By: OVERK1LL
I've noticed no noise with the Fleetguard I've been running on my 5.4L.


You've been running heavier than 5w-20 if I remember one of your posts correctly. So that combo is working good for you it seems. Glad to hear this.
 
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A few years ago I had start-up noise running FL820S's on my Expy's 5.4L. I must have bought some with bad ADBV's. I had 3 of them go bad each within 1000 miles. Everything has been fine since I switched to Napa Gold filters. As for cost, the Napa's cost me $3.08 each bought in a case of 12. They just feel more solid than the Motorcraft, which seems a bit flimsy to me. As to where the bypass valve is located, my opinion is that the valve spends so little time actually in bypass that the amount of contaminated oil entering your engine is inconsequential.
 
Originally Posted By: lyle
A few years ago I had start-up noise running FL820S's on my Expy's 5.4L. I must have bought some with bad ADBV's. .


Maybe I had this all wrong then. I thought start up noise was related to the Bypass valve. Is it actually the ADBV that causes that condition? Or could it just be either?

Any new filter could be defective, regardless of manufacturer, I suppose. I'm surprised you caught trouble with a Motorcraft. Did you happen to buy them all at the same time. Bad batch possibly?
 
The start-up noise was instantaneous on a cold start, and only lasted a split-second. The Motorcrafts were purchased at different auto stores about a month apart, but maybe the same distributor supplies all 3 stores, which were different chains. I've not had the start-up noise ever since I switched.
 
Originally Posted By: Art_Vandelay
Originally Posted By: OVERK1LL
I've noticed no noise with the Fleetguard I've been running on my 5.4L.


You've been running heavier than 5w-20 if I remember one of your posts correctly. So that combo is working good for you it seems. Glad to hear this.


Correct. 5W40. More than half-way through my OCI now.
 
Quote:
Is it actually the ADBV that causes that condition? Or could it just be either?


The ADBV is your source for start up noise, usually. The oil flow has to envelop all the nooks and crannies
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before it pukes out where you need it. If the filter is full or less empty, you're more into a kinetic thing at start up.

If you are empty beyond the filter, and it takes a longer time to envelop the engine, the bypass valve may open due to lack of back pressure. If when you reach envelopment ..and the back pressure is too high for the volume being pumped, the oil pump's relief valve will open ..and again the PSID will be elevated across the filter. It may be high enough to open the bypass.
 
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