Oil Filter Draining Test

ZeeOSix

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It's been mentioned in various threads that when doing an oil change on an engine with the filter mounted vertical and base down, that the filter will typically not drain by itself, and puke oil all over the place when the filter is removed. Punching or drilling a small hole in the dome before removing it will make the filter drain. Some people don't understand why, or didn't think this works so I did this experiment to show how it works.

This filter was mounted vertical base up on a 2010 Mazda3 with the 2.5L 4-cylinder. I did an oil change last week, and removed it when the oil was still pretty hot, then set it base down in a small pan to let it drain for about 3 days. I then put it in a funnel base down and drilled a 9/64 inch hole in the dome end. You can see the oil stream draining out of the filter, and what is seen in the bottom of the glass bottle is after it drained for about 15 minutes. That was with 5W-30 at garage temperature of ~65F, so if you do this with the filter still on the engine an the oil is still pretty warm it's going to drains faster. That was the total volume still trapped and retained in the filter even with it draining for 3 days base down before this test. This also shows that the ADBV was sealing well for 3 days before I put the hole in the dome.

So when the hole is put in the dome, the atmospheric pressure gets into the inside of the filter and breaks the slight vacuum between the media and can shell that was holding the oil back from draining out through the media. It's similar to putting a straw in water, then covering the open end with a finger and pulling the straw out of the water. The water will stay in the straw until the finger is removed from the end of the straw.

I learned this trick decades ago when I had an RX-7 with the filter mounted vertical and base down. First time I did an oil change the filter puked all over the place and made a big mess. I then found out about this trick and have used it ever since. Hopefully someone who doesn't know about this trick can use it in the future.

Photos:
The test setup.
The 9/64 inch hole in the dome.
The oil starts draining quickly, even 5W-30 at room temperature (~65F in the garage).
Pretty good volume came out ... better in the bottle instead of all over the engine, lol.

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^^^ I've tired just loosening the filter some on my Tacoma 4.0L V6 and some oil still leaks out around the base gasket. Punching a hole in the dome works better. If it's quiet in the garage, I can hear the oil draining out of the filter and into the oil pan.
 
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^^^ I've tired just loosening the filter some on my Tacoma 4.0L V6 and some oil still leaks out around the base gasket. Punching a hole in the dome works better. If it's quiet in the garage, I can hear the oil draining out of the filter and into the oil pan.
f you put the Denso filter on it the filter will be completly empty in the morning
 
If you put the Denso filter on it the filter will be completly empty in the morning
When I used Toyota Denso filters for a short time after I bought this truck, they too would puke oil if the dome wasn't punched. Maybe the ADBV in them now isn't so great.
 
So most of it drained into the pan over the three days? That’s about the right amount expected to drain on the clean side. Denso and most do the same. Leave it overnight and unscrews dry. I hear my neighbors 21 Subaru rattle in the morning, sometimes later in the day too. Denso having pretty much the smallest center tube in the business, should hold the most clean side oil up. On the other hand, if the clean side is bigger like Denso, the mass of the oil pushes more. Lol
 
So most of it drained into the pan over the three days? That’s about the right amount expected to drain on the clean side.
No, only what was the residual oil in the center tube was drained out over 3 days. Look at the write-up and the photos. The glass bottle was empty before I drilled the hole in the dome. It had been draining for 3 days before that, so all the residual oil was out of the center tube before doing this test.

Denso and most do the same. Leave it overnight and unscrews dry.
As already said, the back when I ran Toyota Densos, they would puke oil when removed unless I punched the dome and let it drain before removing. Don't know about Densos today, as I don't use them anymore ... not efficient enough for me.

I hear my neighbors 21 Subaru rattle in the morning, sometimes later in the day too. Denso having pretty much the smallest center tube in the business, should hold the most clean side oil up. On the other hand, if the clean side is bigger like Denso, the mass of the oil pushes more. Lol
Doubt the size of the center tube has anything to do with if a filter drains out while sitting or not. Some of it has to do with engine design and also how well the ADBV seals.
 
On a side note, think it was with a Fram Ultra, I wanted to see how well the ADBV sealed while the truck sat for about a week. I checked the oil level and noted it. Then punched a hole in the dome of the filter and let it drain for about 30 minutes. Checked the oil again and the level was up about what I would expect to be inside the filter. So that means the filter didn't drain down through the center tube or the ADBV on the engine after sitting for a week.
 
Stupid question but my airplane’s filter mounts with the open end down and the filter adapters can be fragile, what’s the best way to make the hole in the dome while minimizing any chance of damaging the filter mount’s threads or structure? Drill? Hammer and Nail? Hammer and Punch?
 
Stupid question but my airplane’s filter mounts with the open end down and the filter adapters can be fragile, what’s the best way to make the hole in the dome while minimizing any chance of damaging the filter mount’s threads or structure? Drill? Hammer and Nail? Hammer and Punch?
If you're worried it's that fragile, I'd use a drill and small drill bit, like around a 9/64 inch like I used in this test. If you have a cordless drill it would be fast and easy. I use a sharp punch and hammer on my Tacoma, but I'm not worried about the filter mount. If the punch is nice and sharp it doesn't take much of an impact to make it pierce the filter can.
 
I let it drain a few hours since the oil was only at room temperature. Here's the final amount of oil that was in the filter. Looks like the entire volume on the dirty side of the element was full of oil before I put the hole in the dome and it drained out through the media into the center tube and out. Some of the oil in the media probably drained out too. When I do this on the Tacoma while the oil is still hot, it only takes about 15 minutes to drain to the point where no oil comes out when the filter is removed from the engine.

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I let it drain a few hours since the oil was only at room temperature. Here's the final amount of oil that was in the filter. Looks like the entire volume on the dirty side of the element was full of oil before I put the hole in the dome and it drained out through the media into the center tube and out. Some of the oil in the media probably drained out too. When I do this on the Tacoma while the oil is still hot, it only takes about 15 minutes to drain to the point where no oil comes out when the filter is removed from the engine.

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Did you cut this filter yet?
 
Public Service Announcement:
To some, not all.
Be sure to crack the filter loose before piercing it.
It's not that you wouldn't be able to remove a stubborn filter.
It's so you can avoid the 'wave of horror' feeling if you can't make your pierced and dripping filter move at first.

Knowing how good we all are here, I suppose this applies more to vehicles with unknown, brutish oil change histories.
 
No, only what was the residual oil in the center tube was drained out over 3 days. Look at the write-up and the photos. The glass bottle was empty before I drilled the hole in the dome. It had been draining for 3 days before that, so all the residual oil was out of the center tube before doing this test.


As already said, the back when I ran Toyota Densos, they would puke oil when removed unless I punched the dome and let it drain before removing. Don't know about Densos today, as I don't use them anymore ... not efficient enough for me.


Doubt the size of the center tube has anything to do with if a filter drains out while sitting or not. Some of it has to do with engine design and also how well the ADBV seals.
I read and looked and understood just fine. One thing, the engine you have used to have a stand pipe in earlier versions. You said this somewhere else. So Toyota has done something to alleviate the drain down problem seen in other makes on yours. Stand pipes were used on other vehicles as well. They didn’t go through the extra cost for no reason to add a stand pipe.
Toyota filters have excellent silicone adbv’s. They stick like a suction cup, whip city has been noticing some adbv stick like that and others don’t. I’ve noticed it too.
 
Public Service Announcement:
To some, not all.
Be sure to crack the filter loose before piercing it.
It's not that you wouldn't be able to remove a stubborn filter.
Yes, if someone isn't sure about getting the filter off then loosen it a little so you know it's going to come off without a fight before punching the hole in the dome.
 
I read and looked and understood just fine. One thing, the engine you have used to have a stand pipe in earlier versions. You said this somewhere else. So Toyota has done something to alleviate the drain down problem seen in other makes on yours. Stand pipes were used on other vehicles as well. They didn’t go through the extra cost for no reason to add a stand pipe.
I don't think you fully understood, thinking what was in the bottle was in the center tube based on your comment of: "So most of it drained into the pan over the three days? That’s about the right amount expected to drain on the clean side."

I never showed what amount drained out of the clean side before doing this test because it didn't matter. The oil shown in the bottle is only what was on the dirty side of the filter, after it had sat for 3 days with the base down, before putting the hole in the dome end.

If you research the whole Toyota V6 truck engine series, there is no stand pipe used anywhere, and besides if there was a standpipe it would be in the spin-on filter - and there isn't a standpipe in the filter. The 2005-2015 Toyota 1GR-FE 4.0 V6 is the only one that has the oil filter mounted vertical base down on top of the engine. All others either use a spin-on on the lower side of the engine or a cartridge filter.

Toyota filters have excellent silicone adbv’s. They stick like a suction cup, whip city has been noticing some adbv stick like that and others don’t. I’ve noticed it too.
If Toyota Denso filters are leaking down (as mentioned in post 4), then it could be the ADBV. Like said, I never seen any indication they did when I used them a long time ago. I still had to punch a hole in the dome to drain it completely.
 
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I don't think you fully understood, thinking what was in the bottle was in the center tube based on your comment of: "So most of it drained into the pan over the three days? That’s about the right amount expected to drain on the clean side."

I never showed what amount drained out of the clean side before doing this test because it didn't matter. The oil shown in the bottle is only what was on the dirty side of the filter, after it had sat for 3 days with the base down, before putting the hole in the dome end.

If you research the whole Toyota V6 truck engine series, there is no stand pipe used anywhere, and besides if there was a standpipe it would be in the spin-on filter - and there isn't a standpipe in the filter. The 2005-2015 Toyota 1GR-FE 4.0 V6 is the only one that has the oil filter mounted vertical base down on top of the engine. All others either use a spin-on on the lower side of the engine or a cartridge filter.


If Toyota Denso filters are leaking down (as mentioned in post 4), then it could be the ADBV. Like said, I never seen any indication they did when I used them a long time ago. I still had to punch a hole in the dome to drain it completely.
If you could stop trying to entrap people with words it would be nice. It was a guess, since you put up a pic, I don’t know exactly how much your filter holds on the dirty side. Lighten up.
That’s right, the Toyotas don’t drain down more than other filters with excellent adbvs, as you experienced.
You said something about a stand pipe on the 4.0, maybe on the FJ. I didn’t say it, it was either another member or you. I think it was you who said it, because I never heard of that stand pipe before.
 
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