Powerstroke 6.7L oil drain-back concern; filter?

[ZeeOSix]

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.

It's hard to believe that 2 quarts of oil would drain out of every oil gallery in just a few minutes like Dave's test seems to show. One thing I don't like about Dave's time to get oil to the turbo pedestal test is that the oiling system is open to ATM at that point. He should shove a rubber stopper in that oil exit hole right after stopping the test, and remove the rubber plug right before running the test again. It's possible that ATM pressure on the system at that point could be causing the oiling system to drain down when it wouldn't if the turbo assembly was actually mounted on the engine.

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.

The only way for oil to flow past the oil filter and back towards the pump would be past a leaking ADBV. If oil is back flowing into the center hole of the filter, the only way it can leave the filter is through the base place holes, and the ADBV is meant to seal and stop the back flow through the base plate and back towards the oil pump.

 

[sdowney717]

It's hard to believe that 2 quarts of oil would drain out of every oil gallery in just a few minutes like Dave's test seems to show. One thing I don't like about Dave's time to get oil to the turbo pedestal test is that the oiling system is open to ATM at that point. He should shove a rubber stopper in that oil exit hole right after stopping the test, and remove the rubber plug right before running the test again. It's possible that ATM pressure on the system at that point could be causing the oiling system to drain down when it wouldn't if the turbo assembly was actually mounted on the engine.


The only way for oil to flow past the oil filter and back towards the pump would be past a leaking ADBV. If oil is back flowing into the center hole of the filter, the only way it can leave the filter is through the base place holes, and the ADBV is meant to seal and stop the back flow through the base plate and back towards the oil pump.

I agree about the ADBV blocking flow, but not all filters have that.
I don't know if all Powerstrokes have ADBV filters, originally had assumed they did not because so much oil was leaking back to pan in Dave's video.
But people have posted filters that do.
My Cummins 5.9 has no ADBV.
I don't know if there is a valve in the Cummins oil cooler.

 

[ZeeOSix]

I don't know if all Powerstrokes have ADBV filters, originally had assumed they did not because so much oil was leaking back to pan in Dave's video.

If it was a specified Motorcraft FL-2051-S or FL-2124-S then those filters do have an ADBV. I doubt he would put an unspecified Motorcraft on the engine.

 

[Fair enough]

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.

There is a pipe coming in and one going out of the filter mount. There are gaskets preventing the two sides mixing coming in and out. Or the mount is cast into the block with the in- out pipes apart. It is like a u trap in operation. There is a big oil pump with precise small gaps that the oil must leak down through.
If he says the rod bearings are never bad, why do the mains go? It has to be for other reasons than these four seconds while cranking slowly. Four seconds was the improvement.

 

[ZeeOSix]

The term "U trap" really only applies to the plumbing under the sink. Even in that case, if there is a fluid above the U trap, there will still be flow through it. A filled sink still drains through the U trap when the stopper is removed. So in an engine, if there is nothing like an ADBV to stop all the oil above the filter from back flowing due to gravity, then oil will want to drain down to the point where the head pressure from the oil above the oil pan level equalizes and the back flow stops. There could be sections of the oiling system where oil is still trapped depending on the design of the system, but gravity is going to cause oil above the level in the oil pan to drain back through any path it can find unless there is something to prevent it from doing so - like an ADBV and/or a vacuum lock of trapped oil, similar to the phenomena you see with a base down vertical oil filter not draining unless a hole is punched in the dome to allow ATM pressure inside the dome end.

Like pointed out in Dave's test, that open port at the turbo pedestal where they were watching for an oil stream is open to ATM pressure, and that will most likely cause the system to want to drain back more than if the turbo was installed. He should have put a rubber plug in that hole between test runs to see if that prevented the drain back while the engine sat not rotating.

 

[Fair enough]

The term "U trap" really only applies to the plumbing under the sink. Even in that case, if there is a fluid above the U trap, there will still be flow through it. A filled sink still drains through the U trap when the stopper is removed. So in an engine, if there is nothing like an ADBV to stop all the oil above the filter from back flowing due to gravity, then oil will want to drain down to the point where the head pressure from the oil above the oil pan level equalizes and the back flow stops. There could be sections of the oiling system where oil is still trapped depending on the design of the system, but gravity is going to cause oil above the level in the oil pan to drain back through any path it can find unless there is something to prevent it from doing so - like an ADBV and/or a vacuum lock of trapped oil, similar to the phenomena you see with a base down vertical oil filter not draining unless a hole is punched in the dome to allow ATM pressure inside the dome end.

Like pointed out in Dave's test, that open port at the turbo pedestal where they were watching for an oil stream is open to ATM pressure, and that will most likely cause the system to want to drain back more than if the turbo was installed. He should have put a rubber plug in that hole between test runs to see if that prevented the drain back while the engine sat not rotating.

It functions just like a u trap. That was the context here.
I can tell you from experience of being on the roof clearing the vent pipe that the kitchen sink does not drain if the vent is fully sealed. Sometimes air from the sewer pipe will make its way up and there are glugs of air so the sink drains slowly. The water has mass so wants to go down.
Here the engine turns off and all the pipes are full. If a gasket on the oil filter adapter is hardened or has a crack, it allows the oil in the galleries to slowly descend because air is venting the oil.
If the adapter gaskets are sealed the oil has to go past the adbv. For siphoning to occur from the pan, that’s pulling the adbv down to seal more, not open up.
Oil also drains readily from the engine to the pan in various ways. I can’t see the large pickup pipe empties and the time was 8 seconds to fill all that plus prime the pump. Then he puts a check valve in the pipe and only changes it 4 seconds.

On your Tacoma the filter stays full. On Subarus it seems they don’t. Baxter even makes an adapter with a check valve in it to solve the drain down issue. So what exactly Toyota did hasn’t been found yet.
All out of thoughts for now. Good, other readers say.

 

[ZeeOSix]

It functions just like a u trap. That was the context here.
I can tell you from experience of being on the roof clearing the vent pipe that the kitchen sink does not drain if the vent is fully sealed. Sometimes air from the sewer pipe will make its way up and there are glugs of air so the sink drains slowly. The water has mass so wants to go down.

A "U-trap" will balance itself based on the size of the U. A U-trap will allow flow to the point where the head pressure on the inlet side equals the head pressure on the outlet side. More importantly, do you know the reason for a U-trap on all the plumbing in the a house.

But regardless, there are no actual designed "U-traps" inside an engine like there is under a sink ... that was the point. When an oil filter is removed for an oil change, all the oil above the filter will drain out of the engine galleries as much as the gallery design will allow. And ATM pressure will be introduced on the supply run from the pump, so that could make the pump also leak back oil to the sump. There could be sections of the system that don't drain in that case dependent on how convoluted the oil gallery system is. Just like on that Powerstroke in the video where Dave shows the convoluted path the oil takes from the sump to the filter and then the main gallery. What the oil filter is removed on the engine there's certainly going to be some trapped oil in that convoluted flow path.

Here the engine turns off and all the pipes are full. If a gasket on the oil filter adapter is hardened or has a crack, it allows the oil in the galleries to slowly descend because air is venting the oil.
If the adapter gaskets are sealed the oil has to go past the adbv. For siphoning to occur from the pan, that’s pulling the adbv down to seal more, not open up.
Oil also drains readily from the engine to the pan in various ways. I can’t see the large pickup pipe empties and the time was 8 seconds to fill all that plus prime the pump. Then he puts a check valve in the pipe and only changes it 4 seconds.

In the engine he ran the test on, it was rebuilt so highly doubt there were any leaking gaskets on the oil filter adapter. It's still possible that the ADBV in the oil filter was leaking.

Also, in the test he did, that large pipe was only primed by low RPM so was it really totally full or did it still have some trapped air in it that allowed that big pipe between the pump and sump to drain every time the engine was not running. Seems that way since he showed even after just a couple of minutes the system had drained down again. Plus, for that to happen with that entire pick-up pipe completely full of oil, the filter ADBV would have to leak like a sieve.

And having that oil feed port on the turbo pedestal open to ATM could have cause the oiling system to drain back through other paths. They should have plugged that port every time the engine wasn't turning.

If the same test was done on a compete engine that was fired up and ran to much higher RPM for awhile to ensure every cubic micrometer of volume of the oiling system was bled of air, would the test results be the same? What do people measure in the field on start-ups where the engine has sat for 5 min, 1 hour, 12 hours, 24 hours, 48 hours. That's the test that matters. His test has some flaws that don't reflect an engine sitting in someone's driveway.

On your Tacoma the filter stays full. On Subarus it seems they don’t. Baxter even makes an adapter with a check valve in it to solve the drain down issue. So what exactly Toyota did hasn’t been found yet.

Like said, every oiling system is unique. I've let my Tacoma sit for a couple of weeks and the oil pressure light goes off in 2 seconds just it does if it only sits for an hour. It doesn't drain down when it sits.

 

[dnewton3]

For reference, most of the aftermarket filters for the 6.7L PSD do indeed have ADBVs in them.

 

[Fair enough]

It could be this oil filter adapter gasket fails, which acts like a leaky adbv or oil bypass. This one is for the engine they are working on.

 

[ZeeOSix]

It could be this oil filter adapter gasket fails, which acts like a leaky adbv or oil bypass.

If the gasket was leaking, it would also be puking oil all over the place when the engine is pumping oil.

 

[Fair enough]

If the gasket was leaking, it would also be puking oil all over the place when the engine is pumping oil.

Everything I said was correct. The small common section of gasket separates the in and out to the oil filter. The housing might seep a little on the block also, not gush, but not if just the common section leaks. Some adapters have a separate block gasket, this one doesn’t. Search ebay for used oil filter adapters for this engine to see how it works. On an older engine it would be a good idea to replace the gaskets on the oil filter adapter if it has one.

 

[ZeeOSix]

Everything I said was correct. The small common section of gasket separates the in and out to the oil filter. The housing might seep a little on the block also, not gush, but not if just the common section leaks.

So Dave claims all 6.7L Powerstrokes "leak down" the oiling system like he claims. So every oil filter mounting gasket is defective on these engines and causing this drain back issue? Don't think so. You think a small leak like you describe is going to drain the system down is a couple of minutes like he showed in his "test"?

Some adapters have a separate block gasket, this one doesn’t. Search ebay for used oil filter adapters for this engine to see how it works. On an older engine it would be a good idea to replace the gaskets on the oil filter adapter if it has one.

You think Dave would actually rebuild an engine and allow an old defective gasket on the oil filter housing? And if it was that bad it would probably show some external leakage too.

 

[Fair enough]

So Dave claims all 6.7L Powerstrokes "leak down" the oiling system like he claims. So every oil filter mounting gasket is defective on these engines and causing this drain back issue? Don't think so. You think a small leak like you describe is going to drain the system down is a couple of minutes like he showed in his "test"?


You think Dave would actually rebuild an engine and allow an old defective gasket on the oil filter housing? And if it was that bad it would probably show some external leakage too.

I never said Dave didn’t put new gaskets in, but the engines he gets in for repair I bet quite a few have hardened gaskets. Also it isn’t known what gasket he put in or a mistake wasn’t made. You have no more idea than I do. I didn’t bring thst aspect up, you did.
I went to ebay to look at used adapters for this engine. Yep, first one came up had a flattened gasket. The leak can be substantial. It allows the vented oil above to run down.
The thing he said about rod bearings never are a problem shouldn’t be ignored.
I am not going into a back and forth with you. I can see you have a problem with it.
It’s like, this is not very important, any of it.

 

[ZeeOSix]

I never said Dave didn’t put new gaskets in, but the engines he gets in for repair I bet quite a few have hardened gaskets.

I didn't say you said he didn't put new gaskets in, lol. You think if the oil filter adapter gaskets were a problem that he wouldn't know that by now after working on 100s if not 1000s of these engines?

Also it isn’t known what gasket he put in or a mistake wasn’t made.

Pretty hard to make a mistake installing that gasket. It goes in one way, and it's just a rubber gasket. If he did put a new one in, you think these guys are going to make a mistake installing it after doing 1000s of these engine?

You have no more idea than I do. I didn’t bring thst aspect up, you did.

You're the one that came up with this theory in post 29. If you don't think you brought it up when you clearly did, well I can't help ya there, lol.

I went to ebay to look at used adapters for this engine. Yep, first one came up had a flattened gasket. The leak can be substantial. It allows the vented oil above to run down.

If you look at that rubber gasket, it can only leak in one small area to cause what you describe. And of course used ones are flat because they have been crushed for years ... but that doesn't mean they leak. And if that small section between the two oil passages did leak, it would be a super small leak because the filter housing is tightened flush to the block, so the leak gap would be minuscule ... not some "substantial" leak like you think.

The thing he said about rod bearings never are a problem shouldn’t be ignored.

No it shouldn't, and this is one reason I think his bench "test" is flawed. Like I said earlier, a test with an accurate oil pressure gauge needs to be used on an engine in a truck to determine the oil pressure lag on start-ups. Again, the test with the turbo pedestal oil feed hole open to ATM pressure is suspect. With a fully assembled engine, that port wouldn't be exposed to ATM pressure on the oiling system.

I am not going into a back and forth with you. I can see you have a problem with it.
It’s like, this is not very important, any of it.

I have not "problem with it" ... whatever that means. I have a problem with Dave's bench test for the reasons I've stated a few times now.

Maybe you should contact Dave and let him know the real cause is the oil filter adapter gasket ... see what he says.

 

[Gravity_Wolves]

Could be a worn out oil pump

 

[ZeeOSix]

The area of the red circle is the only place it could leak to cause oil to bypass the oil filter when the engine is shut off - and not cause any external leaks. If the whole gasket was hard, shrunk or cracking all over the place, you'd think there would also be some external leakage going on.

But as I mentioned above, the oil filter adapter is also tight up against the block (why the used gaskets are somewhat "flattened") so there would essentially still a super small leak gap even is the gasket was leaking there. There is no way the amount of oil that Dave claims to have drained down in 2-3 minutes in his bench test is going to flow through a super small leak path like that.

 

[sdowney717]

Dave is blaming the burnt bearings in these motors on this large oil flow back to the pan, emptying out the oil pump and oil galleries.
Then Dave fixes it by using the one way valve in the suction tube.

I imagine this could be a bigger problem when oil is super thick and cold in the winter.

Since these motors are being rebuilt, Dave would have new rubber seals in place.

How many seconds is too long for a bearing to have no oil pressure?
More than 1 second is too long. Bearings do wear out when they are under pressure and no oil is flowing, even if they have slight residual oil left, it is just not a good situation for the longest possible life.

That is why some engines have a pre oil electric pump to recharge the oil galleries before a start up.

 

[ZeeOSix]

As mentioned, why would the main bearings go out and not the rod bearings. The main bearings get oil before the rods, and rod bearings have more risk of wear and damage than main bearings if they are just operating on a left over oil film due to the combustion and reciprocating mass forces. I don't think his bench test is adequate enough to really know what's going on in the field. He needs to do real word testing on a fully assembled engine in a truck.