VANOS Oil Leak

[coh661]

Was scanning through some photos i had taken from my AC system refresh and i noticed this. At first i figured it was a small weep from the oil pan but looks like the oil stains run higher up. I did a visual check from the top side of the engine bay and couldn't notice any oil stains. The plastic engine cover beneath looks pretty clean so it's probably not a major leak. I'll check my dip stick but I've never had a oil light come on. I'd get under to take more photos but it's too cold so I'll probably just wait until spring to investigate further. Any comments or suggestions on the cause and severity (I know it's just 1 photo )

[Steeler]

If it was a non M I would say Oil Filter Housing Gasket. Not sure of the S54 Construction in that area

[dc_wright]

Originally Posted by dbarton62

If it was a non M I would say Oil Filter Housing Gasket. Not sure of the S54 Construction in that area

S54 OFH is in same location as M5X and N5X engines. Design is similar across all of the BMW I6 engines. S5X filter cover is metal is the only real difference.

[coh661]

Looks like there could have been a leak from the Oil filter housing. Not sure from this pic. I'm going to check the CPV valve, sounds like that could be a possibility. Honestly I'm shooting in the dark until I get under the car to inspect.

[GuidoK]

Could be a lot of things, one of the vanos gaskets, one of the timing case gaskets, crankshaft seal, a sealing ring from one of the banjo bolts in the oil feed circuit, chaintensioner seal, constant pressure valve etc.
Start cleaning, start driving, start diagnosing.

Or just leave it, good against the rustworm.

[SaltyNC]

Originally Posted by milamookie

Looks like there could have been a leak from the Oil filter housing. Not sure from this pic. I'm going to check the CPV valve, sounds like that could be a possibility. Honestly I'm shooting in the dark until I get under the car to inspect.

I was thinking CPV valve could be a possibility, since they are known to leak. Looks like fun getting to that sucker. There is a YouTube of someone doing it on an E46 M3.

At least that oil housing cap didn't get oil on it. Shiny!

Salty

[coh661]

Originally Posted by SaltyNC

I was thinking CPV valve could be a possibility, since they are known to leak. Looks like fun getting to that sucker. There is a YouTube of someone doing it on an E46 M3.

At least that oil housing cap didn't get oil on it. Shiny!

Salty

I found that video for the CPV repair, looks like a biatch but an M3 forum member sells a kit which includes an improved gasket and a removal tool. But I'm thinking it's not the CPV as those leaks usually run down the right side of the engine towards the rear. I'm thinking it's probably the crankshaft seal. Found this pic on pelican. Looks right where my oil stains are. I'll know more when I get the car on stands tomorrow. Will report back

[coh661]

Well i was able to get the car up on stands today. I removed the cooling fan and engine under tray just so I could get a better look.

It appears that the leak is originating from somewhere behind the Vanos solenoid and flowing down the block. At first I thought it was from the Timing chain tensioner since that had a bunch of oil collecting on it but looks to be higher than that and i can't imagine that throwing oil across and up the block. It's hard to see exactly how high this is coming from since the lower radiator hose is in the way. I'm thinking it's the Vanos Gasket. Not sure how difficult it would be to remove the vanos housing. I've done a valve adjustment myself so i know i can get as far as getting the valve cover off. Any input on where you guys think the leak is and how hard it would be to replace a Vanos Gasket? I think my next step is to do a clean/drive/inspect again.

[SaltyNC]

Here is a good thread with some links. It has some Z4M specifics like removing the hood release cable retainer.

http://www.zpost.com/forums/showthread.php?t=1048461

Salty

[SaltyNC]

I'm probably not telling you anything you don't already know, but the engine splash guard M10 bolts are meant to be replaced and not re-used. They torque to 59Nm (44 ft lb) and then angle torque to 90 degrees.

EDIT: The torque above is for the E46 M3. I assume it is the same for the Z4M, but should confirm.

I don't get why BMW would use that type of bolt there, but maybe it's more structural and not just a splash guard.


Salty

[coh661]

Originally Posted by SaltyNC

Here is a good thread with some links. It has some Z4M specifics like removing the hood release cable retainer.

http://www.zpost.com/forums/showthread.php?t=1048461

Salty

Thanks Salty,

I spent a couple hours last night reading up on the VANOS repair procedures and I must admit they seem quite daunting for my skill level. I could probably do the repair that just requires removing the solenoid and changing out the o-rings but I'm not %100 sure that's where my leak is coming from.

If the leak is coming from the VANOS gasket the whole VANOS has to be pulled and that's pretty intimidating. This really sucks because I just had done a valve adjustment a couple months back. If I would of known about this leak than I could of attempted to take care of it than.

I might just need to find an Indy to do the repair and maybe while in there I can have them do any recommended upgrades. Since my car has already been winterized I may just wait till spring which could give me some time to work up the courage to do it.

One other thing. I'm just a tad worried that the leak is coming from a blown head gasket but the oil looks to be coming from higher up. Any suggestions on whether this could be a head gasket?

I'm also open to any suggestion on how everyone else would handle this going forward.

[dc_wright]

Take a look on the intake side of the cylinder head to see if there's any oil in that area toward the front of the engine. If there is oil there, it's another sign the OFH gasket is the leak source.

[coh661]

Originally Posted by dc_wright

Take a look on the intake side of the cylinder head to see if there's any oil in that area toward the front of the engine. If there is oil there, it's another sign the OFH gasket is the leak source.

Nothing on the intake side so I'm thinking it isn't the OFH gasket. Here's another photo looking right up at the vanos. Red arrow shows where I think the oil is coming from. Basically right at the Joint where the VANOS mates up with the head. I'm thinking I should inspect that VANOS bolt right there to see if it's loose. Not sure if I can squeeze a hex tool in there without removing the solenoid.

[Beedub]

the s54 is quite a wet engine, mines only got 13k miles and i can see a few slightly wet areas in diff locations , agreed this is slightly worse than average wet area, look forward to seeing this resolved and GL, always abit worrying on such a low clean car :-(

[coh661]

Originally Posted by Beedub

the s54 is quite a wet engine, mines only got 13k miles and i can see a few slightly wet areas in diff locations , agreed this is slightly worse than average wet area, look forward to seeing this resolved and GL, always abit worrying on such a low clean car :-(

The plus side of this is that I've learned a lot about the VANOS system in the last couple days. Shocking how many inherent flaws it has. After a lot of reading I'm 50/50 on whether I want to try this repair myself. A couple days ago i was like "no way in hell I'm trying that".

Another plus is this could give me a chance to address a lot of the known VANOS issues (hub tabs, bolts, seals etc) and be done with it.

I'll keep everyone posted as my story progresses.

[Beedub]

Originally Posted by milamookie

The plus side of this is that I've learned a lot about the VANOS system in the last couple days. Shocking how many inherent flaws it has. After a lot of reading I'm 50/50 on whether I want to try this repair myself. A couple days ago i was like "no way in hell I'm trying that".

Another plus is this could give me a chance to address a lot of the known VANOS issues (hub tabs, bolts, seals etc) and be done with it.

I'll keep everyone posted as my story progresses.

TOTALLY agree, once its out, throw the lot at it if you can , but also dont be fooled by the net, their are plenty of these vanos systems that have run on for 100k plus miles with zero issues....

But i agree with you they basically appear to be a time bomb LOL..... mines an 06 with only 13k miles and i going to pull mine soon as i'm led to believe i have the older bolts which CAN back out.

[coh661]

Originally Posted by Beedub

TOTALLY agree, once its out, throw the lot at it if you can , but also dont be fooled by the net, their are plenty of these vanos systems that have run on for 100k plus miles with zero issues....

But i agree with you they basically appear to be a time bomb LOL..... mines an 06 with only 13k miles and i going to pull mine soon as i'm led to believe i have the older bolts which CAN back out.

After much reading over the past several days I'm convinced I can do it myself. I have a coworker with an E46 M3 that has to do his car so we will walk through it together. I plan on replacing all the usual suspects (pump disc with smaller openings, all cam & hub bolts, chain guides, all gaskets and o-rings). Going to clean out the solenoid and replace all seals. I see this as an opportunity to advance my repair skills. Let's hope after it's done I don't have a very expensive paper weight on my hands.

[Steeler]

Originally Posted by milamookie

After much reading over the past several days I'm convinced I can do it myself. I have a coworker with an E46 M3 that has to do his car so we will walk through it together. I plan on replacing all the usual suspects (pump disc with smaller openings, all cam & hub bolts, chain guides, all gaskets and o-rings). Going to clean out the solenoid and replace all seals. I see this as an opportunity to advance my repair skills. Let's hope after it's done I don't have a very expensive paper weight on my hands.

Learn by doing
After all....a man built it a man can repair it.

[SaltyNC]

Originally Posted by milamookie

Red arrow shows where I think the oil is coming from. Basically right at the Joint where the VANOS mates up with the head. I'm thinking I should inspect that VANOS bolt right there to see if it's loose. Not sure if I can squeeze a hex tool in there without removing the solenoid.

Don't go too tight. 10 Nm or 89 INCH-lbs is torque value on those bolts.

I think it is awesome you are going DIY route. If I had it to do over again, I would have done my own. Guy did a great job on mine, probably about the best that could be done, but I just wish I had gone for it. With the step by step DIYs, it looks very do-able.

Salty

[StickMon]

^WHS. The head is aluminum.
Be particularly careful with the one that has the tab for the accumulator line.
Mine's stripped, and I'm not alone.
The extra thickness of the tab leaves insufficient thread engagement.

And don't lose too much sleep over that relatively minor leak.
Mine's been totally soaked in that area for years.

[Westersund]

I had a very small oil leak from the cam chain tensioner. You might as well check to see if yours is tight enough. Oil has a way of getting to places where you don't expect. Yours look to be very oily around the cam chain tensioner.

[Beedub]

Originally Posted by Westersund

I had a very small oil leak from the cam chain tensioner. You might as well check to see if yours is tight enough. Oil has a way of getting to places where you don't expect. Yours look to be very oily around the cam chain tensioner.

agree with this