[gT-BMW]

alright guys, Im sick and tired of putting a quart of oil every time i put gas!!! I want to do something about it!!!

I got a 2006 325i 6spd 208k miles that drinks oil that ive been putting off for awhile because i was thinking about selling it but now its the right time for me to address this issue and i need help!!

I was thinking about replacing the engine, but it purss like a kitten it just burns a ton of oil.

so I need guidance of how to replace the valve stem seals without removing the head.

I'm ready to purchase the equipment and parts needed to do this job.

anybody got a link to any how tos? or can guide me?? any help is appreciated!


pic:

[Saico]

Are you sure it's valve stems? More likely piston rings is what goes first in N52s. Can be both though.

Anyway when doing this it is worth replacing the timing chain - I think you will need to remove camshafts anyway so timing tools are needed.

[ptpending]

Originally Posted by Saico

Are you sure it's valve stems? More likely piston rings is what goes first in N52s. Can be both though.

Anyway when doing this it is worth replacing the timing chain - I think you will need to remove camshafts anyway so timing tools are needed.

US delivered 325i e9x had N52B30, not N52B25 as in europe
so they have no issues with piston rings oil consumption

[e90yyc]

I’m not an expert but I don’t think valve stem seals can be replaced without removing the head

[gT-BMW]

Originally Posted by Saico

Are you sure it's valve stems? More likely piston rings is what goes first in N52s. Can be both though.

Anyway when doing this it is worth replacing the timing chain - I think you will need to remove camshafts anyway so timing tools are needed.

im pretty sure the valve stem seals are one of my many issues with oil consumption. Its got the symptoms, it gets smokey.

Is it really necessary to change the timing chain? im hoping i can leave that alone lol

I'm hoping we can get some feedback from people that used there timing tool
to chime in here.

Originally Posted by ptpending

US delivered 325i e9x had N52B30, not N52B25 as in europe
so they have no issues with piston rings oil consumption

Yes it appears so. I did a leak down test on my N52 awhile ago. Only 5 and 6 tested barley within limits. So i dont think i have a piston ring issue.

Its in 5 and 6 i see the blueish color on the valve stem.

Originally Posted by e90yyc

I’m not an expert but I don’t think valve stem seals can be replaced without removing the head

I'm not expert either but there are experts out there, and i hope that this thread catches there interest to chime in!

I really dont want to remove the head lol

[NZE90]

You can replace the valve stem seals without removing the head. I have done it quite a few times. It is a big job. About 12-15 hours with the correct special tooling.

Have you ruled out all other possibilities though like the PCV diaphram for instance?

I just cured an oil consumption issue on an 06 325i by replacing the PCV assembly. The car ran good, no codes, but used oil. The diaphram was split.
There is also an updated PCV oil return hose available to combat oil consumption.

[PhaceN52]

Originally Posted by NZE90

You can replace the valve stem seals without removing the head. I have done it quite a few times. It is a big job. About 12-15 hours with the correct special tooling.

Have you ruled out all other possibilities though like the PCV diaphram for instance?

Quote this, if the PCV is bad it smokes like a chimney

[Saico]

Originally Posted by NZE90

You can replace the valve stem seals without removing the head. I have done it quite a few times. It is a big job. About 12-15 hours with the correct special tooling.

Do you need any more special tooling other than:
1. timing tools
2. spring pushing tool
3. Pneumatic insert to keep the cylinder pressurized
4. Grips to remove old stems

?

[NZE90]

Originally Posted by Saico

Do you need any more special tooling other than:
1. timing tools
2. spring pushing tool
3. Pneumatic insert to keep the cylinder pressurized
4. Grips to remove old stems

?

Yes, you need the tools for removing and installing the eccentric shaft intermediate levers and springs

[Saico]

For this specifically there is a DIY workaround described somewhere, my friend used it and was ok without the tools for removing levers, which are expensive.

[gT-BMW]

Originally Posted by NZE90

You can replace the valve stem seals without removing the head. I have done it quite a few times. It is a big job. About 12-15 hours with the correct special tooling.

Have you ruled out all other possibilities though like the PCV diaphram for instance?

I just cured an oil consumption issue on an 06 325i by replacing the PCV assembly. The car ran good, no codes, but used oil. The diaphram was split.
There is also an updated PCV oil return hose available to combat oil consumption.

Hey thanks for shining some light on this thread! I got a few questions i hope you don't mind answering?

Do you mind sharing the resources that you used to do this job when you first started?

Do you have any recommendations on special tooling thats needed to do this job like a link to it or name?


When you did those valve stem seals, did it stop the oil consumption?

How did you know that the PVC/CCV was the issue in the recent car that you fixed and not the valve stem seals?

From my research a good way of telling that the CCV is bad or going bad is that it will make a whirlling noise at idle.

Opening the oil filler cap to see if the car idle changes

Placing a thin piece of paper on the oil filler cap and observe if that paper is sucking it in or blowing it out.


When i did the 3 stage manifold conversion i replaced the PCV system and hoses and it did not make a difference in oil consumption.

When it was time to replace me DISAs, i noticed oil in my intake manifold, But i was told that is normal. Ive since installed an oil catch can. seems to be working.

So having an external PCV im able to test it by shooting air into the intake side. I can hear the plunger open up and close with a strong return force plunger. on the exit side it holds pressure indicating it doesnt leak.

I hope the community can chime in. Lets get this knowledge!

[NZE90]

Originally Posted by gT-BMW

Hey thanks for shining some light on this thread! I got a few questions i hope you don't mind answering?

Do you mind sharing the resources that you used to do this job when you first started?

Do you have any recommendations on special tooling thats needed to do this job like a link to it or name?


When you did those valve stem seals, did it stop the oil consumption?

How did you know that the PVC/CCV was the issue in the recent car that you fixed and not the valve stem seals?

From my research a good way of telling that the CCV is bad or going bad is that it will make a whirlling noise at idle.

Opening the oil filler cap to see if the car idle changes

Placing a thin piece of paper on the oil filler cap and observe if that paper is sucking it in or blowing it out.


When i did the 3 stage manifold conversion i replaced the PCV system and hoses and it did not make a difference in oil consumption.

When it was time to replace me DISAs, i noticed oil in my intake manifold, But i was told that is normal. Ive since installed an oil catch can. seems to be working.

So having an external PCV im able to test it by shooting air into the intake side. I can hear the plunger open up and close with a strong return force plunger. on the exit side it holds pressure indicating it doesnt leak.

I hope the community can chime in. Lets get this knowledge!

I used to work at a dealer so all the tools were genuine BMW ones. Yes i believe it did cure it. N52 valve stem seal issues aren't very common. It's very common on the V8s and 4 cylinders though.

You can test the PCV using a Mityvac. There is a vacuum nipple on top of the valve. You simply connect the Mityvac and apply vacuum and see if it holds the vacuum.

[gT-BMW]

sup e90

so long story short i cannot drive my car anymore because im putting a quart of oil in it twice a week so its parked up.

Put it off for so long now i gotta do something about it.

So i had to buy a teslaong inspection camera to find out where this oil burning issue is coming from.

Turns out my suspesion was wrong its not the valve stem seals it is actually the head gasket it self?



I've included a video for reference.


What do you guys think about this? Should i replace the head gasket or replace the engine?

[NZE90]

It's not the head gasket, there is only one oil supply gallery to the head, so if it was the head gasket it would only leak on No1 cylinder.

It is impossible to say what the exact cause of oil consumption is without dismantling the engine. It's either the oil control rings, PCV or valve stem seals. I would just get a second hand engine if you are 100% certain the PCV is not the culprit.

Did you ever check it holds vacuum and the return hose to the oil pan is not blocked?

[NZE90]

Contrary to what everyone says, the N52b30 DID have issues with oil control rings. I have seen the BMW service bulletin regarding it.

[gT-BMW]

Originally Posted by NZE90

It's not the head gasket, there is only one oil supply gallery to the head, so if it was the head gasket it would only leak on No1 cylinder.

It is impossible to say what the exact cause of oil consumption is without dismantling the engine. It's either the oil control rings, PCV or valve stem seals. I would just get a second hand engine if you are 100% certain the PCV is not the culprit.

Did you ever check it holds vacuum and the return hose to the oil pan is not blocked?

I can confirm its not the CCV. Actually i wasnt sure if the hose and CCV was aftermarket so i bought a brand new OEM CCV from FCP as well as new OEM hoses.

The smoking issue actually got worse. seems like $$ down the drain.

This is really stressing me out..

Thank you for your input on this.

I took another video of the exhaust valves in cylinder #2. Pretty much all the cylinder exhibit the same issues. oil leaking down from what seems to be the exhaust valves.

However above the exhaust valves is dry???

At this point im not sure if its the valve stem seals or the oil control rings.

What do yall think?

[PhaceN52]

Maan that's A LOT of residue, with valves being dry i'd point to oil control rings... if you have the tools and feel like pulling the engine and rebuilding it while sending the head to a machine shop for cleaning it in a bath go for it, or swap it for another engine
Download and install INPA/TIS or ISTA, there you have all oem procedures and torque values
If you go for the rebuild route I think you can leave the crankshaft in place without separating the bedplate and sealing it after, seems doable

[NZE90]

The oil from leaking valve stem seals usually comes from the intake valves due to the vacuum in the manifold. Are the intake valves wet with oil?

[gT-BMW]

Originally Posted by NZE90

The oil from leaking valve stem seals usually comes from the intake valves due to the vacuum in the manifold. Are the intake valves wet with oil?

I havnt had a chance to verify this as i work 6 days a week and this weekend was the spence-crawford fight so havnt touched the car.

I did try to take endoscope videos of the intake valves but it barley opens when rotating the engine.

However when i did removed the intake manifold a month ago to do the ccv swap, the intake valves and manifold was dry of oil.

I guess it looks like im looking at a engine swap?

I dont have time for a rebuild as of right now my back up car is a g35x sedan.

My local junkyard sent me a pic of the availble n52b30 they have in stock. Not only is it missing the exhaust manifold but some exhaust ports look wet.

This is looking to be a headache for even finding a good long block. any have suggestions on choosing a long block?

[fastboatster]

Can’t you try looking at your local pick n pull or pick a part yards? There’re many e90s at junkyards now, and n52d are pretty much not needed by anybody and almost never get pulled. Probably can try to pull one out yourself. eBay or car-part can be a source

[NZE90]

I would want to inspect the engine in person, pull the spark plugs out and make sure they don't have any oil carbon on them. Maybe even put your camera in the cylinders and check the bores, valves etc.

[crashoverride]

Valve stem seal failure is such a rarity on this engine. Not that anything and everything can break but this isn't a common failure for this engine.

Obviously a repair this big the expense is more than the car is valued... and for many of us here it's worth the expense. But it's not worth fixing such a rarity should it not solve the problem.

It would be well worth the diagnosis cost to take it to your dealership and have them professionally explore the many different causes and properly diagnose.