Powerstroke 6.7L oil drain-back concern; filter?

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Was watching a Dave's video and he adds in a check valve in the large oil pickup tube in the pan
Says he is fixing a lot of Powerstrokes with spun and wiped out bearings due to bad oiling system design.

Thoughts?


 
Bad oil system design? I disagree. If the ADBV isn't doing its job after each shutdown cycle, that's a failure of the filter, not Ford's design. Why would Dave blame Ford for a malfunctioning ADBV in a filter?
 
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Cummins 5.9/6.7 engines don't have have drain back valves in the filter nor in the block. If you do an oil change after sitting long enough, the filter can is only 2/3 fill because the oil drains back when parked until air breaks the suction across the top of the filter element.

I always figured a perfect ADBV meant the motor would have oil as soon as it started, but in reality, even if the filter prevents the pickup/pump/filter circuit from going dry, the galleys will all drain out the lowest point (crank bearings?) while the motor sits.

And how much do we really expect a rubber flap against a punched filter plate to realistically form a tight seal against gravity?

To Dave's credit, the oiling path from pickup to pump to cooler to filter is really long on the 6.7 PSD and keeping it primed will be a head start on everything else.
 
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Bad oil system design? I disagree. If the ADBV isn't doing its job after each shutdown cycle, that's a failure of the filter, not Ford's design. Why would Dave blame Ford for a malfunctioning ADBV in a filter?
AFAIK, Powerstroke filters do not have ADBV.
Except for that Fram Titanium FS10890.
If I had a Powerstroke Diesel, I would use that Fram with ADBV to help solve the problem.

I know my Cummins filters do not have ADBV either
I looked up Fram Titanium for my Cummins 5.9, and there is not ADBV in them either.
 
Here are the results from a similar test that was done as part of a study on cold starts (SAE 922384):

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The Powerstroke took around 7 seconds to build oil pressure at the turbo, with room temperature oil. The 14.6 L heavy duty diesel engine from the study had a similar result with higher viscosity oil (15W-40 at around -5°C), so the Powerstroke seems to perform worse.

The engines in the study all developed main bearing damage even though all tests were done with an oil MRV of <15,000 cP, well under the accepted limits of 30-60,000 cP. Since the Powerstroke seems to perform even worse than the engines in the study, Dave is probably correct that the main bearing damage he's seeing is from lack of oil pressure on cold starts. His shop is in Utah, and a lot of his customers are going to be doing engine starts in very cold weather.

Other studies on cold starts using smaller gasoline engines don't seem to show the same bearing wear issues, since they tend to have a lot less oil volume to fill up.
 
Here are the results from a similar test that was done as part of a study on cold starts (SAE 922384):

The Powerstroke took around 7 seconds to build oil pressure at the turbo, with room temperature oil.
I'm betting Dave's engine stand turns far less than 1800 RPM, so not all "seconds" before oil are created equally.
 
I'm betting Dave's engine stand turns far less than 1800 RPM, so not all "seconds" before oil are created equally.
According to Dave in the video, the engine was turning at "less than 600 rpm", so probably close to 600 rpm. The first few seconds were at a lower speed to simulate cranking. I'm not sure what the ramp-up time was in the study.

In the study, they did tests at both 600 and 1800 rpm, and there was little difference between them. In both cases, the oil pump's pressure relief valve would have been open, so pressure and flow would be regulated to similar values.

1752168544768.webp
 
According to Dave in the video, the engine was turning at "less than 600 rpm", so probably close to 600 rpm. The first few seconds were at a lower speed to simulate cranking. I'm not sure what the ramp-up time was in the study.

In the study, they did tests at both 600 and 1800 rpm, and there was little difference between them. In both cases, the oil pump's pressure relief valve would have been open, so pressure and flow would be regulated to similar values.

View attachment 288802
Those are significant delays to getting oil pressure.
Then you have some who won't pre-fill their big oil filters, will just add more time to finally getting some oil to the bearings.
I have always prefilled engine oil filters.
 
After watching the 2nd video I see that even after 2-3 minutes of sitting it still takes a pretty long time to get oil out of the turbo pedestal. That does indicate that the oiling system is draining down way faster than I would suspect. Does that Motorcraft oil filter have an ADBV? If not, then he should find a filter that does have one and try that testing in the 2nd video with a filter with a good ADBV.

I'm wondering of the open oil port at the turbo pedestal has any factor in the oil draining down in the system. It allows ATM pressure to act on the oil passages, whereas if the turbo was installed the system would be sealed from ATM pressure. They should plug that hole right after a run and then unplug that hole right before another test run.
 
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Those are significant delays to getting oil pressure.
Those times are also reflective of pumping a 15W-40 at 0C and below temperatures. At 0C the time is pretty short, and the time in that graph is to the turbocharger which is down stream somewhat from the pump. 138 kPa is 20 PSI. I'm assuming there wasn't any oil drain back to the pan in those tests, but who knows.
 
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Some searching shows that the Motorcraft FL-2051-S was originally specified for the 6.7 Powerstroke, and that the FL-2124-S supersedes the FL-2051S. Looks like both have an ADBV.
 
The Donaldson P502503 has a silicon ADBV, this filter is pretty popular due to the 99% efficiency rating @ 15 micron with Powerstroke owners.

 
Where do rod bearings get their oil from, I forgot. The stock oiling system seems to work well.
From holes cross drilled in the crankshaft to the rod journals, and the rod bearings then also get fed oil that was fed to the crank bearings from a main gallery.
 
So question is, does the ADBV actually prevent oil from draining back on the Powerstroke?
Or is it useless, the oil supply pipes to the filter are huge, maybe the oil can escape those huge pipes even with ADBV

The oil drains out all the way to the filter itself. draining inlet tube pickup, oil pump and tube to the oil cooler and tube to the oil filter.
Every time the oil pump has to reprime itself on starting and refill all the way to the filter, and then has to push all the trapped air through the oil upper oil passages.

That is a lot of oil draining out and it is a design problem, I think.
 
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So question is, does the ADBV actually prevent oil from draining back on the Powerstroke?
Or is it useless, the oil supply pipes to the filter are huge, maybe the oil can escape those huge pipes even with ADBV

The oil drains out all the way to the filter itself. draining inlet tube pickup, oil pump and tube to the oil cooler and tube to the oil filter.
Every time the oil pump has to reprime itself on starting and refill all the way to the filter, and then has to push all the trapped air through the oil upper oil passages.

That is a lot of oil draining out and it is a design problem, I think.
Unless an oring is bad on the oil filter adapter or further down, the oil filter and lower pipes aren’t vented and stay full. The filter always stays full, it’s like a u trap. An adbv helps keep the oil above the filter from draining. I doubt the bearings are being damaged by oil starvation. That’s what he did, put an anti drain valve in. He didn’t shave that much time off, it still took a few seconds.
I used to crank engines with foot to the floor to build oil pressure on those that could do that. It took at least 8 seconds.
The part where he says I never see rod bearings damaged, how does that support his theory?
 
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Unless an oring is bad on the oil filter adapter or further down, the oil filter and lower pipes aren’t vented and stay full. The filter always stays full, it’s like a u trap. An adbv helps keep the oil above the filter from draining. I doubt the bearings are being damaged by oil starvation. That’s what he did, put an anti drain valve in. He didn’t shave that much time off, it still took a few seconds.
I used to crank engines with foot to the floor to build oil pressure on those that could do that. It took at least 8 seconds.
The part where he says I never see rod bearings damaged, how does that support his theory?

I think if you took a 1.25" pipe full of hot oil on it's side, and opened up one side wide open, all the oil will drain out of the tube.
What I don't know is if one end is submerged in the sump (the pickup), will prevent that from happening.

I also do not know if in his test, the oil filter number, has an ADBV or not.

If the filter does not have ADBV, it makes sense all the oil will drain back to the sump. There is a lot of oil sitting in the oil galleries above the sump oil level.

A filter is not a u trap like a pipe, oil flows through the paper element across every level of oil in the filter.
Oil will remain in the filter can and not drain, but oil will flow across the top interior of the filter through the top of the paper element.

That makes sense to me.
 
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