Experience with some old cellulose filters.

I would think a blocked ATF filter would cause an overheated transmission, not a stalling engine. If a torque converter was starved of or low on fluid, it would cause the opposite of stalling, there would be no movement. To the guys above, I know hydraulic filters are usually cellulose, but they're usually a little bigger than an FL-400S/ L20195 size filter. I have a stash of OG Ultra XG8s & Baldwin B2-HPGs just for external ATF filter use, and this issue has never occurred to me.
 
I’m not trying to “pull your legs”) I’m not trying to be smart or sound very knowledgeable.
I’m simply sharing my experience and the conclusions I think I’ve made.
I was always talking about my buddies car. I never said it was my car. I even posted in a prior thread about the filter I took off and replaced with the FL400s before these events. I followed up in this thread.
My recent research (I’m not just pulling random ideas out of my head) helped me to acquire my theory for why the filters went into bypass. Absolutely, they were in bypass.
Machinery lubrication has an article titled The Effects Of Water Contamination On Oil Filters for example and they seem to think too much moisture in an oil filter can cause it to clog.
I learned about the probable bypass sitting on those filters and concluded that the transmission probably struggled to create enough pressure to open them at low speeds or rpm’s
As far as my belief that the transmission was was starving for fluid, I dunno, you tell me a better theory.
Perhaps my terminology is not the best. Maybe it’s more accurate to say the car was shuttering at low rpm’s. It didn’t do so at higher rpm’s, it didn’t do so in park but in gear sitting still, initially accelerating and slowing to stop it would do it. It stalled a couple times reversing out of the driveway.
You have a good point in that the fluid has to be present somewhere in the system but it was certainly struggling going back into the pan to be taken back up. The system apparently wasn’t pressuring up enough to burst a line or the filter case or even rip through the media but it was definitely restricting flow enough to cause the events I’ve described. It’s not doing it with the current filter I put on and it didn’t do it before with other filters. Not even with the cellulose filter that initially came with the remote mount he bought.
I do know that a transmission low enough on fluid is gonna struggle and if it’s very low the vehicle ain’t gonna move. I know if the pump is shot and it’s not flowing sufficiently enough, again, it’s gonna struggle.
So whatever, I’m cool with being wrong if I am or not fully understanding what’s going on but I don’t think it’s it cool to have my character attacked because of it.
If you have knowledge to share you could probably do so without contention and still feel good about yourself.
Regarding the stuttering/sputtering effects, I remain skeptical, but I'll take you at your word for I have no ability to prove otherwise.

Let's approach this from your perspective. You want to know if enough moisture is in the air that it will cause a cellulose oil filter to essentially blind off the pores? I rather doubt it. That would infer horrible consequences for nearly any filter which sits on a shelf at any dealership, service center or John Doe's garage anywhere it's "humid" (essentially anywhere that isn't the desert southwest). Yet we never hear of oil filters failing due to their celluose media absorbing atomspheric water. So I doubt the air is supplying enough moisture content to make a filter fail in the manner you describe. I store some of my filters in my barn; it gets super-humid in summer around here. I also cut open my filters after use; always curious to see what I can find. I've never come across a cellulose media so swelled from water that it couldn't pass lube. I find that premise difficult to swallow; that the moisture in air is enough to essentially make the media swell shut, for a lack of a better word.

Perhaps the moisture is actually in the tranny fluid? If that is the case, the using the celluose filters is actualy beneficial to your application. Use several of them, and they will eventually get the moisture out of your system. Using a syn media filter won't do squat to remove the moisture; it cannot aborb anything in the media itself.

You said it yourself ... the cellulose filter was OK for about a day, and then problems started happening. I doubt the filter was contaminated from sitting around; it probably got water in it from the tranny fluid. If your fluid is heavily contaminated with moisture, it may be a good idea to just do a couple drain/fill cycles before going through several filters.

And, take a UOA of the fluid and see what that tells you as well.
 
^^^ Yeah, the fact that it took a day or two for the issue to occur says it's possible the filters clogged from something in the ATF. How old was the ATF ... maybe it was pretty dirty and cleaned up after two filters were used on it - ??.

As far as the filter feeling hot or not during extended use ... the FL400S has a base plate bypass valve so if it was in bypass the can wouldn't get very warm/hot. The PH3600 has a dome end bypass, so even if it was in bypass the can should still be pretty warm/hot.
 
Here's a few ML articles that allow some insight.

- for a filter to essentialy be a problem, the water content has to reach the saturation point
- the tested filter in the ML article had a pore size of 3um; WAY smaller than a typical FL400S (or equivilant)

I don't think the OP has a filter problem; I think he may have contaminated tranny fluid.
Again - get a UOA on the tranny fluid !!!!


My point is that I SERIOUSLY doubt there's enough moisture in the air to cause a typical cellulose filter to just essentially swell shut. I think it's far more likely the filter was reacting to conditions in the sump well past it's design intent. Heavy water contamination in lube systems can wreak all kinds of havoc.





 
Lots of transmissions have a bypass mechanism, so that if the front mounted cooler or lines get clogged, the transmission fluid just recirculates inside the transmission. You still had pump pressure or you would have sat right there.
 
That V-1A is the same size as a FL-1A Ford filter.

I would have an exceptionally difficult time believing the filter is the cause of any of this.
 
What temps did this occur?
Some vehicles have cooling line thermostats.

If it's very cold out, the temp may not be high enough to cause oil to flow.
 
Lots of transmissions have a bypass mechanism, so that if the front mounted cooler or lines get clogged, the transmission fluid just recirculates inside the transmission. You still had pump pressure or you would have sat right there.
I'm wondering if the ATF cooler have a thermostatically controlled bypass valve. And does the ATF cooler bypass valve have a pressure setting? Maybe the filter delta-p was higher than the cooler bypass valve setting, and the filter and cooler wasn't getting much or any flow. But it's still puzzling if the cooling circuit operates that way (in parallel) that the engine running would be effected.
 
Here's a few ML articles that allow some insight.

- for a filter to essentialy be a problem, the water content has to reach the saturation point
- the tested filter in the ML article had a pore size of 3um; WAY smaller than a typical FL400S (or equivilant)

I don't think the OP has a filter problem; I think he may have contaminated tranny fluid.
Again - get a UOA on the tranny fluid !!!!


My point is that I SERIOUSLY doubt there's enough moisture in the air to cause a typical cellulose filter to just essentially swell shut. I think it's far more likely the filter was reacting to conditions in the sump well past it's design intent. Heavy water contamination in lube systems can wreak all kinds of havoc.





Good reading there, thanks. I actually think I will probably take the advice on sending out a uoa simply because I wanna know.
 
What temps did this occur?
Some vehicles have cooling line thermostats.

If it's very cold out, the temp may not be high enough to cause oil to flow.
It was about as cold for DFW for sure probably upper 40s
 
^^^ Yeah, the fact that it took a day or two for the issue to occur says it's possible the filters clogged from something in the ATF. How old was the ATF ... maybe it was pretty dirty and cleaned up after two filters were used on it - ??.

As far as the filter feeling hot or not during extended use ... the FL400S has a base plate bypass valve so if it was in bypass the can wouldn't get very warm/hot. The PH3600 has a dome end bypass, so even if it was in bypass the can should still be pretty warm/hot.
Well I replaced 4 qts the same time the filter was changed so half new and half of the fluid would have been in use for a good couple years and about 40k miles.
 
Possible the ATF cooler is letting coolant in, or maybe off road in deep water, but the ATF should be a pink milkshake if it's that bad.
Yeah no milk shake.
The fluid was dark reddish and still had the distinct oder that Maxlife atf has.
I do have the old fluid in the garage still.
I’ll try to look at it closer
 
I'll throw this out there too.

Automatic transmissions typically do not play well with moisture it causes the fibers to come apart most of the time if circulated in quantity. I would think any quantity of water sufficient to damage the filter would damage the clutches and bands as well.

The only thing i can think of is the TCC sticking... I have driven a few (late 80's cavilers had a bit of a rash of them when new) cars that the TCC was stuck on in and its like trying to coast to a stop in a stick with the clutch out...
 
I'm wondering if the ATF cooler have a thermostatically controlled bypass valve. And does the ATF cooler bypass valve have a pressure setting? Maybe the filter delta-p was higher than the cooler bypass valve setting, and the filter and cooler wasn't getting much or any flow. But it's still puzzling if the cooling circuit operates that way (in parallel) that the engine running would be effected.

One thing's for sure - if the OP is noting that the external filter is cold coincident with his problem it isn't being bypassed in that filter. A cold filter would indicate a blockage or a bypass upstream of the filter.
 
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One thing's for sure - if the OP is noting that the external filter is cold coincident with his problem it isn't being bypassed in that filter. A cold filter would indicate a blockage or a bypass upstream of the filter.
True for the PH filter with the dome end bypass valve. But the FL Motorcraft has a base end bypass, so it would be hard to tell. But even if the filter was bypassing 100%, the lines going in and out of the filter would still be hot. That would be the better test, feel the lines.
 
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True for the PH filter with the dome end bypass valve. But the FL Motorcraft has a base end bypass, so it would be hard to tell. But even if the filter was bypassing 100%, the lines going in and out of the filter would still be hot. That would be the better test, feel the lines.

Ah, yes. Didn't catch that the Motorcraft as a base bypass.
 
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