Oil smoke on start-up with my '95 540

[johnf95037]

Hi All,

I recently changed my CCV hoping it was the culprit in the oil burning on start up and an occasional belch during operation. I now don't get the belch, only the smoking during start-up.

There seems to be a buildup of oil in the intake manifold that pools when the car sits for a few hours or more. On start-up it burns off.

I'm looking at changing the oil separator and o-rings behind the front timing cover. Is there a write up on how to do this? I have a Bentley manual, but it is a little light in this area.

Any gottchas?

Thanks,
-j

'95 540 244k mi

[imae30driver]

Its the valve guides....

A drop will run down the valve stem into the camber and burn off on start up. Not really a concern... Happens to most hi milage motors IMO

[HE53]

Its the valve SEALS....

A drop will run down the valve stem into the camber and burn off on start up. Not really a concern... Happens to most hi milage motors IMO

Fixed.

[Binjammin]

Its the valve guide seals....

A drop will run down the valve stem into the camber and burn off on start up. Not really a concern... Happens to most hi milage motors IMO


Fixed.

Fixed.

Also, it may very well be not the valve guide seals, it could very easily be the OSV (the one on the front of the engine under the timing covers)

Lots of e38 guys run an oil catch can to solve this issue, but I think the line that drains the OSV to the pan gets clogged up and blocked, the oil can't drain, so it ends up in the intake.

[cardanigen]

Its the valve guides.http://fashionold.com/4e.jpg

[Sankekur]

Most likely the valve stem seals. Have the same issue with a big puff of oil smoke when I start up (intermittent), replaced the PCV on the back of the intake but doesn't seem to have done anything.

When I had the intake off it looked like only one of the seals on the intake side at least was leaking as only one valve was really dirty compared to the others.

Strangest thing about this is even the motor is run against compression there is almost no smoke, but park it on a level surface for a couple of hours and it will smoke at startup.

[Binjammin]

There seems to be a buildup of oil in the intake manifold that pools when the car sits for a few hours or more. On start-up it burns off.




Most likely the valve stem seals. Have the same issue with a big puff of oil smoke when I start up (intermittent), replaced the PCV on the back of the intake but doesn't seem to have done anything.

When I had the intake off it looked like only one of the seals on the intake side at least was leaking as only one valve was really dirty compared to the others.

Strangest thing about this is even the motor is run against compression there is almost no smoke, but park it on a level surface for a couple of hours and it will smoke at startup.

If it was valve guide seals, there would be no mechanism for oil to be transferred to the intake manifold.


Like I said... if the drain for the OSV is clogged, oil will be fed up to the intake manifold. If the car sits while off, a puddle of oil will drip into each intake port, and puff off at startup. Fix the OSV issue and the oil problems will go away.

[Trasportador]

Here is a great write up on the osv and pcv function. Bin's above statement is correct based on your symptoms.

http://www.meeknet.co.uk/e31/BMW_M60_M62_M62TU_Engine_Crankcase_Ventilation.htm

[johnf95037]

Great write up because for one, it clears up confusion between the OSV and CCV (PCV). Secondly it nicely diagrams and describes the function of each.

I had ruled out the valve guide seals as well because of the oil in the intake manifold. The guides may be contributing, but I don't believe they are the major culprit.

How big of a job is it to replace the OSV? I've heard recommendations to replace the timing chain guides while in there.

Thanks,
-j

[Trasportador]

Great write up because for one, it clears up confusion between the OSV and CCV (PCV). Secondly it nicely diagrams and describes the function of each.

I had ruled out the valve guide seals as well because of the oil in the intake manifold. The guides may be contributing, but I don't believe they are the major culprit.

How big of a job is it to replace the OSV? I've heard recommendations to replace the timing chain guides while in there.

Thanks,
-j

Im contemplating the chain guides now. I've already pulled up my intake, taken off the water pump, I'm technically right there. . Found too much oil in the intake manifold, so will have to get the osv and a new pcv as well. Lord, this is getting expensive. I really wanted to start driving the 5 and give the 7 a rest, but to no avail. By the time I'm done with the m60 it had better purr like a sumatran tiger, I swear.

[johnf95037]

I installed RD sway bars, HR lowering springs and Bilsteins so it corners flat, a little rougher ride than stock though. My wife wasn't happy with me the first time she drove the car after the suspension mods. But honey, look how it handles. Hmmm!

We've since bought my wife a new car due to reliability issues with an aging beast. So now, with the car down I can sort through the maladies and bring back some of it's youth.

-j

Thanks,
-j

[Trasportador]

Sounds like a good plan man. Keep us posted