Valve cover gasket again??

[SHI X5]

My X5 had a slow leak last year. A drop or 2 in my garage daily (oil). So after a while i took it to the stealer, and they replaced my Valve Cover Gasket at 85,000 miles, ssaid that was it. I have an 01 3.0. It didn't leak for 5 months. Now it is doing it again. Few drops. Think it is same thing? Is that possible? They are looking at it Friday, but made it clear they are charging me and if it's same thing they will replace free. thoughts???

thanks guys!!

[bigpenterprise]

it happens to me too twice the second time two cylinders was broken i had to pay 3500$ to rebuild my motor and mine is a 4.4 01 with 178 000km so make sure that the garage check the engine before putting a new valve cover.good luck

[alpac]

The job may have not been done right the first time.

[aranka]

im going through that as we speak and my guys have checked all of the following; valve cover gaskets, pcv valve, the drip tube from valley to sump (dont know name), and finally a spacer plate gasket on the front of the engine. this all came about when the temp hit single digits. is there any recourse from BMW NA?

[primetime]

No recourse from BMW NA trust me... And yes the cold weather will start to show more problems for the X. Our cars just don't like cold weather in general.. All my problems came to serious levels, all during the winter, never in any other season. Last year I spent thousands of dollars getting this fixed. VCG, New Valve cover, Oil Seperator, you name it...

[lo_jack]

For what it is worth, I will tell you in my opinion:

Valve cover gaskets do not just fail. There is not supposed to be positive pressure on these seals. This is the kind of thing that people who add forced induction to cars that were not built for them plan for in their design. When you pressurize the motor, oil comes out of the easiest point(s). This would be seals. Motors destined to be boosted are designed to relieve pressure from the crankcase so this does not happen.

So what, why should you care?

When you take your BMW X5 to the dealer for a valve cover gasket, odds are really high that your separator is shot, and is causing pressurization of your motor. Pressurization of your motor is not SOP. Therefore, when you take your BMW X5 in for a leaking valve cover gasket, the dealer should, in my opinion, automatically check your separator system for compromisation. This should include a thorough check of the hoses, a mental note of the climate and presence or lack of updated hoses, and pulling of the adjuster unit to check for oil in the intake manifold.

They are not fools. They know this is the root cause of valve cover gaskets going at 60k or whatnot. But they will send you back out with a junk separator and a new valve cover gasket. Ask them why.

If they tell you this is not the situation, then then you can at least ask them why your BMW X5, and many like it, go through valve cover gaskets at the same rate as tires, when every other major manufacturer and indeed, most other BMWs, can manage to put a car on the streets with VCGs that last a minimum of 100k in most instances.

That is just my opinion.

[TwinsPoppa]

Just to be clear about the pressurization portion.

Are you saying that the valve cover gaskets are being OVER pressurized - NOT that the X5 system does not normally pressurize the valve cover gaskets at all.

It's just that, from what I gathered on other threads, I was under the impression that the system is normally pressurized.

I understand the part about the separator and such causing excess pressure.

Originally Posted by lo_jack

For what it is worth, I will tell you in my opinion:



Valve cover gaskets do not just fail. There is not supposed to be positive pressure on these seals. This is the kind of thing that people who add forced induction to cars that were not built for them plan for in their design. When you pressurize the motor, oil comes out of the easiest point(s). This would be seals. Motors destined to be boosted are designed to relieve pressure from the crankcase so this does not happen.



So what, why should you care?



When you take your BMW X5 to the dealer for a valve cover gasket, odds are really high that your separator is shot, and is causing pressurization of your motor. Pressurization of your motor is not SOP. Therefore, when you take your BMW X5 in for a leaking valve cover gasket, the dealer should, in my opinion, automatically check your separator system for compromisation. This should include a thorough check of the hoses, a mental note of the climate and presence or lack of updated hoses, and pulling of the adjuster unit to check for oil in the intake manifold.



They are not fools. They know this is the root cause of valve cover gaskets going at 60k or whatnot. But they will send you back out with a junk separator and a new valve cover gasket. Ask them why.



If they tell you this is not the situation, then then you can at least ask them why your BMW X5, and many like it, go through valve cover gaskets at the same rate as tires, when every other major manufacturer and indeed, most other BMWs, can manage to put a car on the streets with VCGs that last a minimum of 100k in most instances.



That is just my opinion.

[primetime]

I think lojack is saying that something has to give when there is pressure built up in the crankcase. The Valve Cover gasket is usually the weakest point so thats where it will give..I've seen others where the oil cap pops off or unscrews on its own when the pressure is built up too much also..The VCG is usually the first area to give way though..

[TwinsPoppa]

Hmmm ... maybe I wasn't being clear and/or I'm misunderstanding something. I'm referring to these passages in bold:

Originally Posted by lo_jack

For what it is worth, I will tell you in my opinion:

Valve cover gaskets do not just fail. There is not supposed to be positive pressure on these seals. This is the kind of thing that people who add forced induction to cars that were not built for them plan for in their design. When you pressurize the motor, oil comes out of the easiest point(s). This would be seals. Motors destined to be boosted are designed to relieve pressure from the crankcase so this does not happen.

So what, why should you care?

When you take your BMW X5 to the dealer for a valve cover gasket, odds are really high that your separator is shot, and is causing pressurization of your motor. Pressurization of your motor is not SOP. Therefore, when you take your BMW X5 in for a leaking valve cover gasket, the dealer should, in my opinion, automatically check your separator system for compromisation. This should include a thorough check of the hoses, a mental note of the climate and presence or lack of updated hoses, and pulling of the adjuster unit to check for oil in the intake manifold.

They are not fools. They know this is the root cause of valve cover gaskets going at 60k or whatnot. But they will send you back out with a junk separator and a new valve cover gasket. Ask them why.

If they tell you this is not the situation, then then you can at least ask them why your BMW X5, and many like it, go through valve cover gaskets at the same rate as tires, when every other major manufacturer and indeed, most other BMWs, can manage to put a car on the streets with VCGs that last a minimum of 100k in most instances.

That is just my opinion.

[lo_jack]

Originally Posted by TwinsPoppa

Just to be clear about the pressurization portion.

Are you saying that the valve cover gaskets are being OVER pressurized - NOT that the X5 system does not normally pressurize the valve cover gaskets at all.

It's just that, from what I gathered on other threads, I was under the impression that the system is normally pressurized.

I understand the part about the separator and such causing excess pressure.

To my knowledge, pressurizing the crankcase does not happen in standard ICE engines as an intended consequence. In fact, the opposite is the goal: pulling a vacuum on the crankcase has numerous benefits to performance and longevity of the motor. That is why you get an SES light on many vehicles if your dipstick is not in solidly, or your oil fill cap is off - it messes up the vacuum. If you pressurize the crankcase at all, you risk blowing oil out of it.

Pressurizing the crankcase would confound oiling far too much. I cannot believe the X5 motor is intentionally 'pressurized' at all under normal operation until proven otherwise.

Positive Crankcase Ventilation actively pulls blowby out of the crankcase with vacuum. Blowby is detrimental to the reciprocating assembly and block. The separator is a part of the crankcase ventilation system. However, were you to sling blowby and oil - they are comingled in the crankcase as a side effect of the motor operating - straight back into the intake, you would lean out the AF ratio, foul your plugs, have lousy performance, etc. So the separator removes as much liquid as it can from the byproduct stream and drains it down. The fouled gases go into the intake where they are recombusted in every cylinder via the distribution piece. When this stops working, blowby liquids go into the intake like so:



See the brown goo in the intake ports? That should not be there, since nothing should be there but air, but for emissions purposes is always gathered and reintroduced into the intake track for recombustion.

Racers pull a vacuum on the motor with a belt driven pump, and take the byproduct and vent it rather than put it back into the motor. In fact, the simplest design uses exhaust flow to suck blowby out of the motor and drag it out of the exhaust.

For whatever reason, the engineers felt that too much oil would be consumed in the intake to not physically remove oil from the blowby gasses before it was reintroduced, and because of this you have a separator.

EDIT: Having not taken apart a separator, it is entirely possible, upon further reflection, that its failure generates excessive vacuum, thereby sucking too much goo into the intake, as the system most certainly runs on vacuum at the manifold (like power brake boosters). But pressurization as a default is right out.