N62 engine valve stem seals

[jpcallan]

Originally Posted by Westlotorn

I see a couple people have changed the valve stem seals. Did you look inside the intake manifold prior to doing this job to see if you really needed Valve stem seals?
If your intake was wet with oil your issue was not valve stem seals.

Yes, there were blow-by deposits just behind and beyond the throttle body: degraded oil, dark brown soot, etc. The backside of the throttle body and its butterfly valve were both heavily coated with same. As part of the service work, I flushed the valve cover's PCV passages and the three-connector PCV hose with solvent to clean away as much blow-by gunk as possible; the throttle body got a thorough cleaning as well.

I don't believe the smoking had any anything to do with air leaks. The valve guide seals were in bad shape, it smoked. Now they're new; it doesn't smoke any more.

[Victorious4.8is]

Originally Posted by Westlotorn

I see a couple people have changed the valve stem seals. Did you look inside the intake manifold prior to doing this job to see if you really needed Valve stem seals?
If your intake was wet with oil your issue was not valve stem seals.

I have smoke after a brief idle coming from my 2006 4.8is. I inspected the hose going directly into the top of the intake manifold and there is a decent amount of oil in there. I have already ordered replacement diaphragms for the CCV's. Current ones were torn nearly all the way around. I'll report back the results after the new ones are installed and everything is cleaned and put back together.

As a mechanic, I must say your theory that the culprit of the smoke is not the valve stem seals and the true cause is being masked in the replacement of all the seals during the process of replacing the valve stem seals is very interesting and makes a lot of sense. The symptoms everyone is experiencing is not typical of worn valve stem seals. However, we are dealing with a BMW and anything is possible I guess. My plan is to attack everything else except the valve stem seals. There are several oil leaks on my engine so I'll seal those up first and see what happens. I'll post my results but I think you may be on to something here.

[X5only]

Originally Posted by Victorious4.8is

I have smoke after a brief idle coming from my 2006 4.8is. I inspected the hose going directly into the top of the intake manifold and there is a decent amount of oil in there. I have already ordered replacement diaphragms for the CCV's. Current ones were torn nearly all the way around. I'll report back the results after the new ones are installed and everything is cleaned and put back together.

As a mechanic, I must say your theory that the culprit of the smoke is not the valve stem seals and the true cause is being masked in the replacement of all the seals during the process of replacing the valve stem seals is very interesting and makes a lot of sense. The symptoms everyone is experiencing is not typical of worn valve stem seals. However, we are dealing with a BMW and anything is possible I guess. My plan is to attack everything else except the valve stem seals. There are several oil leaks on my engine so I'll seal those up first and see what happens. I'll post my results but I think you may be on to something here.

Been there and done all that. Intake had oil, pipes had oil, replaced all seals imaginable - twice. Still smoking on extended idle 10-15 minutes when engine is hot. Now doing the valve stem seals and as I remove them, their condition leaves no doubt whose fault it is. I'll post pics later tonight. I see no point of not doing the valve stem seals when you're tackling every other seal - the VSS are just a step away! If the smoking is fixed, well and good. If not, you will have to do it all over again, like I'm doing now

[stiubhartach]

Jus a reminder that many smoking problems are oil suck from a broken CCV membrane and NOT the dreaded valve stem seal.

Always check the easy and cheap CCV system before diving into the expensive valve stem seal repair.

A thread on it:


https://xoutpost.com/bmw-sav-forums/...lem-fixed.html

[mr_robot]

I still don't know what to do about this. E70 was doing but it's gone but now dealing with similar with my 4.8iS.

From Westlotorn I wanna believe it's not my VSS as I don't have any of the symptoms like he described when VSS fail.

I did change both CCV and corresponding hoses but still smoke slightly after extended idle ONLY. I'm due to do all my gaskets soon and if I'm gonna do the valve cover gaskets might as well do the VSS don't you guys think? So I don't have to do things twice?

Currently at 117k miles.

[X5only]

Originally Posted by mr_robot

I still don't know what to do about this. E70 was doing but it's gone but now dealing with similar with my 4.8iS.

From Westlotorn I wanna believe it's not my VSS as I don't have any of the symptoms like he described when VSS fail.

I did change both CCV and corresponding hoses but still smoke slightly after extended idle ONLY. I'm due to do all my gaskets soon and if I'm gonna do the valve cover gaskets might as well do the VSS don't you guys think? So I don't have to do things twice?

Currently at 117k miles.

I too didn't want to believe it was the VSS causing my smoking issue on extended idle. I changed both valve cover gaskets and all the other seals including upper timing cases and the vacuum pump seals. What a waste of time and effort - still smoking on extended idle. I kicked myself hard as I'd done 80% of the valve stem seals work Right now I'm doing the VSS myself in my garage, and I can tell you from the condition of the ones replaced so far, they're definitely the culprit of the smoking - rock hard and with some I could almost see the gap between the seal and the stem after removal.

The major question is why didn't I want to believe it was the VSS? Fear of the difficulty of the work to replace them. I've discovered it's not hard, just time consuming. I watched 10's of DIY videos of VSS replacement to come to this conclusion. And you don't need an air compressor after-all.

[mr_robot]

Yes, just in denial that's all LOL also because it doesn't smoke on extended idle when it's cold, only after it's been warmed up.

[X5only]

Originally Posted by mr_robot

Yes, just in denial that's all LOL also because it doesn't smoke on extended idle when it's cold, only after it's been warmed up.

Yep, same with mine, which is because the oil is still thick.

[mr_robot]

Originally Posted by X5only

Yep, same with mine, which is because the oil is still thick.

Damn...I'll do it soon but going to pay to get it done. Local guy wants $2500 (parts & labor). Found him on another bmw forum and couple guys already got it done by him with good reviews. He's tech at BMW and does this on weekends (backyard mechanic) Now that it's getting super cold plus shorter days, I don't want to deal with this headache.

[CleanIsFast]

When you guys do the VSS, are the seals an upgraded version?