Anti Drainback oil filter housing Valve

[FourRinger14]

Stupid question but if my anti drainback valve is hardened/failing, is it likely it’s also bleeding oil pressure/flow while engine is running? Going to replace tomorrow as I have a short startup chain rattle which is annoying but wondering if it will have other benefits after the immediate cold startup that may quiet other cold ticking/knocking that dissipates after a few minutes after startup? My thought is that if it drains while the engine is shutdown under just gravity it must also be leaking somewhat while running under pressure.

[Fresh.S4]

how often do you change your oil?

i just realized i have my original 140k OFH in a box for some reason,,,,, im gonna go take it apart real quick brb!

[FourRinger14]

Since tuning @ about 142k every 5k
Original housing

[Nillious]

From my experience a failing drain valve will cause a longer rattle after the initial rattle. I wish I had some old video of it. You will hear the initial rattle then and extended rattle as all the air in the housing is bled out. If you hear an immediate rattle that stops that's just the tensioners bleeding down.

You can compare it to a rattle after initial start on an oil change. Pull your filter and allow the oil to drain. Then close it up and start it. You will most likely hear the extended rattle compared to what you hear daily.

The short rattle can only be eliminated by new tensioners or oil check valves. Even with the check valves in place you can hear a very brief rattle for a spit second but a good drain valve and check valves remove 95 percent of the rattle. You can buy the drainback seal from Audi. Pull your spring out of the housing and change it. Only use OEM filters as it has a support sleeve inside to keep the paper from compressing and loosing tension on the drain valve.

[FourRinger14]

Replaced anti-drainback valve. Original one was flat and petrified. We’ll see if any noticable change.

[eurojunkjon]

Do you by chance have a part number for this?

[FourRinger14]

Got it from FCP Euro
VW 06E115475

[Nillious]

That's how mine was. There is actually a tsb due to oil pressure warnings but i cant find it at the moment.

The seal can actually break off eventually and lead to low oil pressure while running.

[DrGrapeApe]

My thought is that if it drains while the engine is shutdown under just gravity it must also be leaking somewhat while running under pressure.

It works as a check valve to keep oil in the filter housing while the car is off. When the engine is running oil pressure pushes it open as it's covering the inlet port for the filter housing.

[FourRinger14]

Ok, after thinking about it that makes sense.
Same as Nillious mentioned, I too was thinking about a TSB I found on some VAG cars with the similar filter housing & drainback valve failure causing low oil pressure. Can’t find it now of course.

[Nillious]

It works as a check valve to keep oil in the filter housing while the car is off. When the engine is running oil pressure pushes it open as it's covering the inlet port for the filter housing.

Just to clarify, This is actually not how it works. Oil is pumped up into the housing through the front port in the housing and goes through the filter and down the center tube where it's distributed to the engine. No oil flows through the drain port unless the filter is lifted out of the housing or the filter cap is loosened allowing the spring to push the filter upwards. The drain valve is there strictly to allow it to drain during an oil change. Problem is when it gets hardened it leaks down even when the filter is pressing on it.

If it fails completely it allow oil pressure to bleed directly back to the pan.

There are actual check valve that work the way you said but they are under the pcv valve in the oil circuit to the entire top end of the motor. Two entirely separate things.

[FourRinger14]

Found it, it’s for the 2015/2016 A6/A7/A8 3.0T for “drain plug being out of place” but seems potentially relevant with a hardened/flat valve that’s not fully sealing on the S4 as well.

[raceshop147]

Audi dealer told me that can’t be changed and the entire housing had to be replaced lol

[FourRinger14]

It does take patience and a few minutes once you get the right picks in the right positions to release the tension on two of the spring’s tabs just enough from the plastic post and lift the spring out. I’m sure the plastic post could be broken, then a new housing would probably be needed. I’d be lying if I said I wasn’t worrying about that while doing the job lol

[Nillious]

Actually that part was never available for the the b8s. They have that part serviceable for the Evo motors cause the oil filter housing is built into the timing cover. It just so happens it works for the older models as well. It will probably work for the 3.2s as well.

The dealership just looks up the part for the b8s and sees it is not offered separately. So anyone who is just an average parts guy who knows how to click buttons wouldn't know any better.

[seanB7]

It would be nice if someone made a video on how to remove the drain back valve.
hint hint

[ericsosa]

Replaced anti-drainback valve. Original one was flat and petrified. We’ll see if any noticable change.

Hmm, I'm curious how mine would've compared next to a brand new seal. I was afraid I was going to be without my daily had I broken something in an attempt to remove the spring

What mine looked like in the housing

Only use OEM filters as it has a support sleeve inside to keep the paper from compressing and loosing tension on the drain valve.

Interesting, are there any comparison pictures of a Hengst or MANN filter next to an OEM filter?

There are actual check valve that work the way you said but they are under the pcv valve in the oil circuit to the entire top end of the motor. Two entirely separate things.

I have mixed feelings about these check valves. Why would Audi remove them if they were so important at mitigating chain/tensioner wear or at the minimum, keep oil in the heads for startup conditions?

[FourRinger14]

It would be nice if someone made a video on how to remove the drain back valve.
hint hint

No video but if you look at the pic here you can see the 4 locking tabs on the left side of the spring. This pic, the spring is upside dow, the rubber valve would be facing down on the paper towel rather than face up. So the tabs are bent such that they lock into fine “ribs” on the post as it is pressed onto the post during intallation. To remove I placed picks under two adjacent tabs and gently pulled up where the tabs lock onto the post to kinda flex the tabs away from the post/ribs, once the picks pulled two tabs away you have some clearance to slide the other two tabs away and pull up. It’s a simple concept but a bit tricky and there is probably a chance to snap the post off if too much pressure applied while trying to get it off.

[FourRinger14]

Hmm, I'm curious how mine would've compared next to a brand new seal. I was afraid I was going to be without my daily had I broken something in an attempt to remove the spring

What mine looked like in the housing

That’s almost exactly what mine looked like from the top, flat with no cup shape and hardened, was giving me about half second of immediate startup rattle on cold start.

The new valve completely eliminated that half second cold start rattle, unfortunately I still have a secondary chain tap/rattle coming from the upper chain cover driver side that starts about 15-20 seconds after cold start and lasts about 1.5 minutes til it quiets back down to normal so I guess I’ll be tackling that when I have the time to take on that project.

[Nillious]

Interesting, are there any comparison pictures of a Hengst or MANN filter next to an OEM filter?

Mann Is the OEM filter. Externally not much different but inside the Mann has a plastic support sleeve. You can see it in this photo https://assets.ecstuning.com/product...0492_x800.webp

It keeps the filter from being able to compress or collapse.

[ericsosa]

Mann Is the OEM filter. Externally not much different but inside the Mann has a plastic support sleeve. You can see it in this photo https://assets.ecstuning.com/product...0492_x800.webp

It keeps the filter from being able to compress or collapse.

Hmmm, good to know. I’ll be buying MANN/OEM from now on.

[A4Qwattro]

I have mixed feelings about these check valves. Why would Audi remove them if they were so important at mitigating chain/tensioner wear or at the minimum, keep oil in the heads for startup conditions?

1) reduce cost

Once the car passes 4yr/50,000 miles, it's not Audi's problem. The check valves only have a benefit at high miles. Audi cuts cost by removing parts that help a car to last outside of the warranty period.

[ericsosa]

1) reduce cost

Once the car passes 4yr/50,000 miles, it's not Audi's problem. The check valves only have a benefit at high miles. Audi cuts cost by removing parts that help a car to last outside of the warranty period.

Hmm, fair enough.

I'll consider installing them if I have to dig out that PCV again. Hoping I don't have to but good luck to future me

[A4Qwattro]

This is probably why aftermarket oil filter housings are not recommended. There's an aluminum one that I have seen on Amazon. It seems ideal otherwise...

[Nillious]

I have the aluminum one from Amazon. The drain back valve did not work correctly. I had bought a uro parts housing and it leaked at the cap no matter what I tried. Then I bought the aluminum one and installed it. Found out it leaked down anytime the car was off for more than a minute. At that point I had changed it twice and wasn't doing it again. I welded an old extension to a tap and threaded the hole the drain valve covers. Got the appropriate bolt and sealing wash and plugged the hole. No more issues with drain back since lol. I extract during oil changes so I just extract from the housing as well since it obviously won't drain.

This is why I always say OEM and OEM only on oil filter housings.

[ericsosa]

I have the aluminum one from Amazon. The drain back valve did not work correctly. I had bought a uro parts housing and it leaked at the cap no matter what I tried. Then I bought the aluminum one and installed it. Found out it leaked down anytime the car was off for more than a minute. At that point I had changed it twice and wasn't doing it again. I welded an old extension to a tap and threaded the hole the drain valve covers. Got the appropriate bolt and sealing wash and plugged the hole. No more issues with drain back since lol. I extract during oil changes so I just extract from the housing as well since it obviously won't drain.

This is why I always say OEM and OEM only on oil filter housings.

Wait, are you still using an aluminum housing or have you since gone back to an OEM housing?

[A4Qwattro]

Actually that part was never available for the the b8s. They have that part serviceable for the Evo motors cause the oil filter housing is built into the timing cover. It just so happens it works for the older models as well. It will probably work for the 3.2s as well.

The dealership just looks up the part for the b8s and sees it is not offered separately. So anyone who is just an average parts guy who knows how to click buttons wouldn't know any better.

and the oil filter housing on the CREC motor is aluminum again...go figure. Seems like a pain if the seals on the oil filter housing on the CREC motor fail. Engine pull.




What is with Audi and stupid designs. It's like the cam cover valve cover on the 2.0T. You practically have to remove the timing chain tensioner to do a valve cover job. What happened to simplicity? . Why does the PCV on these cars have a coolant pass through?

All of these integrated designs are terrible.

[Nillious]

Wait, are you still using an aluminum housing or have you since gone back to an OEM housing?

I am still using the aluminum housing. The drain port is basically disabled 100%. The hole was threaded and I used button head torx bolt with an aluminum sealing washer under it. It's basically an upsidedown drain plug. I have a vacuum extractor for oil changes so I just extract from housing after the oil pan. Next time I have it apart I may put an OEM housing back on but everything is working perfectly at the moment so I'm not messing with it.

[A4Qwattro]

I am still using the aluminum housing. The drain port is basically disabled 100%. The hole was threaded and I used button head torx bolt with an aluminum sealing washer under it. It's basically an upsidedown drain plug. I have a vacuum extractor for oil changes so I just extract from housing after the oil pan. Next time I have it apart I may put an OEM housing back on but everything is working perfectly at the moment so I'm not messing with it.

That sounds neat to be honest. It takes away a potential oil pressure failure point.

[ericsosa]

Why does the PCV on these cars have a coolant pass through?

I've been debating if relocating the PCV would be worth it. You replace the plastic PCV with a metal valley pan from the 3.2L and then route the lines to a separate PCV/Diaphragm above the supercharger. No more cracking coolant lines in the PCV channel and it's a lot easier to repair if the PCV fails again.

Audi C7 Owners made an 8 video playlist on this, seems quite interesting.

I am still using the aluminum housing. The drain port is basically disabled 100%. The hole was threaded and I used button head torx bolt with an aluminum sealing washer under it.

Do you still have the spring in there for the oil filter to sit on?

[Nillious]

The filter doesn't sit on the spring as in being supported on it. It does press on it to close the drain valve but the filter bottoms out and sits on the four raised ridges inside the housing. But to answer your question, no there is no spring anymore as it is not needed in my situation.

[ericsosa]

The filter doesn't sit on the spring as in being supported on it. It does press on it to close the drain valve but the filter bottoms out and sits on the four raised ridges inside the housing. But to answer your question, no there is no spring anymore as it is not needed in my situation.

Hmm, not bad. One less probable headache.

[Fresh.S4]

I'm using a URO oil filter housing and an ECS alum cap.... No leaks, no rattles....

No sure how the cap would affect anything, it's just threaded on.

as for that pcv relocation kit,,, that kit assumes that the diaphram will break and if that was the case, you can swap them out by just removing the sc and its located right on top of the pcv. just replacing the pcv with an oem hengst will reset the life cycle and you'd prob never have a problem for the remaining life of the car. anyone who has already done the pcv job with oem parts shouldnt even consider it. but if you've never done pcv service then that might be the route to take. the other problem with that kit is the intake adapter, it kinda messes with intake/tb setups i would think. im sure folks have been able to overcome that but the fact you gotta change stuff around to make things work is kinda frustrating sometimes.

[A4Qwattro]

On the B8 2.0TDI, they built the anti-drain back o-ring into the oil filter itself. So when oil filter is pulled, it takes the stopper with it so the oil in the filter housing drains back into the pan. That rubber always got replaced with each oil filter change



This rubber drain back valve should definetely be a service item on these cars. That rubber will flatten and collapse after all this time but of course Audi doesn't care about any car after 4 years so information like this is not shared except amongst enthusiasts.

[raceshop147]

Progress, innovation, ingenuity, luxury, and the spirit of exploration!!!!

[raceshop147]

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[raceshop147]

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[Corydms7]

Mine only has a brief same rattle on startup after adding the check valves and switching to Motul oil. Do you think that replacing the oil filter housing gasket would completely eliminate the rattle altogether?

From my experience a failing drain valve will cause a longer rattle after the initial rattle. I wish I had some old video of it. You will hear the initial rattle then and extended rattle as all the air in the housing is bled out. If you hear an immediate rattle that stops that's just the tensioners bleeding down.

You can compare it to a rattle after initial start on an oil change. Pull your filter and allow the oil to drain. Then close it up and start it. You will most likely hear the extended rattle compared to what you hear daily.

The short rattle can only be eliminated by new tensioners or oil check valves. Even with the check valves in place you can hear a very brief rattle for a spit second but a good drain valve and check valves remove 95 percent of the rattle. You can buy the drainback seal from Audi. Pull your spring out of the housing and change it. Only use OEM filters as it has a support sleeve inside to keep the paper from compressing and loosing tension on the drain valve.

- - - Updated - - -

Brief small rattle***

[Nillious]

I don't believe there is anything you can do other than tensioners for that. That is how mine is after check valves. Very brief rattle about half a second. You have eliminated the large air pocket that forms in the oil channels after the check valves however the check valves cannot stop a tensioner from leaking down.

The check valves keep the oil channels full from the inner tube of the oil filter housing. The outer portion is what drains down when you have a bad drain valve. If your filter housing were draining down you would hear another rattle about one second after a quiet start.

Mine went in this order.

No check valves and bad drain valve. About a 3-4 second rattle sometimes longer. Hot starts after the engine was off for more than 10 minutes was a quiet initial start followed by about a 2 second rattle as it bled the air out of the channels ffrom the housing draining down.

Repaired drain valve. About a three second at most rattle on start. Breif initial rattle hot start after about a half hour.

Added check valves. Never rattles unless it's off overnight. Rattle is so breif you need to actually listen for it. This is as good as it gets without new tensioners.