Metal VANOS Cover Failure - MUST READ!

GORDON.M3 wrote

If these vanos covers are subject to such high stress that the clips could fall off, I am sure the plastic one would have exploded and caused many engine failures already.

I for one think it's an installation error or faulty batch. I doubt the vanos covers are subjected to such high levels of strength that the clips would de-latch themselves.

Or the vanos covers were not machined properly from the jump and the dimensions are off with Slon and the replicas that were failing.

while i do generally agree with you, it's worth noting that since the OEM design was a contiguous cap it wouldn't deform the same way even if it were a weaker material.

Why was the solution to this problem, make a new design with different materials, why not 3D scan the oem and reman them. Wouldn’t it be cheaper as well? They last 13 years no problem on mine. New oem I will buy if they are made. Next it will be bolts backing out from improper install on the washers and cups.

e92dud wrote

Why was the solution to this problem, make a new design with different materials, why not 3D scan the oem and reman them. Wouldn’t it be cheaper as well? They last 13 years no problem on mine. New oem I will buy if they are made. Next it will be bolts backing out from improper install on the washers and cups.

Low volume plastic production is kind of a non-starter financially. Plus not sure we know the actual material used.

kolosy wrote

Low volume plastic production is kind of a non-starter financially. Plus not sure we know the actual material used.

So it would be more expensive than the aluminum?

e92dud wrote

Why was the solution to this problem, make a new design with different materials, why not 3D scan the oem and reman them. Wouldn’t it be cheaper as well? They last 13 years no problem on mine. New oem I will buy if they are made. Next it will be bolts backing out from improper install on the washers and cups.

That's how most of the current covers are made. However, there are discrepancies when scanning, and not to mention its not possible to buy those covers brand new from BMW. I would only scan and replicate the covers on the basis of a new unit to make sure the tolerances are all correct.

That being said, I'd still think that aluminum is the way to go and plastic should not be used in the engine due to the heat and aging.

e92dud wrote

So it would be more expensive than the aluminum?

Substantially. A steel injection molding tool can run 50-100k on its own so you’d need hundreds orders just to cover the cost of that.

Aluminum can be cnc machined which is slower and more expensive at volume but doesn’t have the upfront cost of plastic.

GORDON.M3 wrote

That's how most of the current covers are made. However, there are discrepancies when scanning, and not to mention its not possible to buy those covers brand new from BMW. I would only scan and replicate the covers on the basis of a new unit to make sure the tolerances are all correct.

That being said, I'd still think that aluminum is the way to go and plastic should not be used in the engine due to the heat and aging.

Timing chain guides?

Oem last longer than valve cover gasket, seems like it would be a good combo service. Too bad bmw didn’t make any to sell.

e92dud wrote

Timing chain guides?

Known to fail later on in the high mileage S65 ownership life. Timing Chain guides are made of plastic because metal ones would grind away at the chain. There's no grinding action on the Vanos cover so you can use metal in this application.

The Ferrari 458 V8 doesn't even use any covers and the spring is fully exposed.

GORDON.M3 wrote

Known to fail later on in the high mileage S65 ownership life. Timing Chain guides are made of plastic because metal ones would grind away at the chain. There's no grinding action on the Vanos cover so you can use metal in this application.

The Ferrari 458 V8 doesn't even use any covers and the spring is fully exposed.

I was referencing the plastic shouldn’t be used in the engine part. BMW would make the engine block out of plastic if they could find a way to make it last till the warranty expired.

Can the OEM plastic covers be bought on their own?

MechEngineer408 wrote

Can the OEM plastic covers be bought on their own?

Bmw doesn’t sell them on their own

Here's another design for the aluminum covers:

https://vargasturbo.com/product/vtt-s65-7075-vanos-covers/

The design looks pretty stout with more clip area than competitors. However, the vendor has some pretty bad reviews regarding its other products.

One tends to have time to think when semi-retired.. So I had another thought on the topic of cracked OEM plastic covers. "What IF the OEM plastic covers are actually fine longterm and only crack when damaged during valve cover replacement clumsy servicing trauma? In other words, what if the assumption that the plastic covers are brittle is wrong? Could the phenomena of cracked OEM plastic covers be caused by bumping them hard with a valve cover during gasket replacement work? And not noticing the crack damage trauma until later on...IF not then what would cause the plastic cracking in the first place as well as the crack propagation?
.

.

DrFerry wrote

One tends to have time to think when semi-retired.. So I had another thought on the topic of cracked OEM plastic covers. "What IF the OEM plastic covers are actually fine longterm and only crack when damaged during valve cover replacement clumsy servicing trauma? In other words, what if the assumption that the plastic covers are brittle is wrong? Could the phenomena of cracked OEM plastic covers be caused by bumping them hard with a valve cover during gasket replacement work? And not noticing the crack damage trauma until later on...IF not then what would cause the plastic cracking in the first place as well as the crack propagation?
.

.

I've thought about this. I've got about 65k miles on my M3 and the covers look mint still, the gaps between them are perfectly straight and the covers don't show any sign of failure/wear. Original valve cover also, so the motor was never tampered with that's for sure.

I'm curious if the plastic one also fails due to a service error or mistake. Maybe the oil funnel pushed in too hard when filling oil and damaged the covers, or like you said situations where the valve cover was replaced and it was knocked.

What I did notice when installing my friend's Slon ones, was that the OEM side on which had the oil cap opening was the side that had problems. The other driver-side vanos covers were absolutely mint and showed no sign of warping/misalignment. This also makes me think about the phenomenon you've brought up.

GORDON.M3 wrote

I've thought about this. I've got about 65k miles on my M3 and the covers look mint still, the gaps between them are perfectly straight and the covers don't show any sign of failure/wear. Original valve cover also, so the motor was never tampered with that's for sure.

I'm curious if the plastic one also fails due to a service error or mistake. Maybe the oil funnel pushed in too hard when filling oil and damaged the covers, or like you said situations where the valve cover was replaced and it was knocked.

What I did notice when installing my friend's Slon ones, was that the OEM side on which had the oil cap opening was the side that had problems. The other driver-side vanos covers were absolutely mint and showed no sign of warping/misalignment.

Thanks, that's great information and thinking 'Doctor Watson'. The Sherlock Holmes in me says 'we might be onto something'. I’ll come out from behind the couch now. My GA-Tech mechanical engineering Profs used to say failure modes can be simple and obvious once rigorous observations are applied.

Remember the space shuttle disaster of the early eighties? Turned out to be launching in freezing temps caused the booster rocket gaskets to become brittle and contracted. Duh. Anyway, I digress.

I like your theory of simple trauma to the oil fill passenger side vanos cover, versus no damage trauma to the driver’s side cover. Thanks again. I wonder if anyone else has noticed such a correlation?

Imagine if a mechanic rammed a metal funnel into the oil filler mouth at an angle. Perhaps cracking or fractures could occur and then propagate due to circumferential loads and hot temps.

GORDON.M3 wrote

I've thought about this. I've got about 65k miles on my M3 and the covers look mint still, the gaps between them are perfectly straight and the covers don't show any sign of failure/wear. Original valve cover also, so the motor was never tampered with that's for sure.

I'm curious if the plastic one also fails due to a service error or mistake. Maybe the oil funnel pushed in too hard when filling oil and damaged the covers, or like you said situations where the valve cover was replaced and it was knocked.

What I did notice when installing my friend's Slon ones, was that the OEM side on which had the oil cap opening was the side that had problems. The other driver-side vanos covers were absolutely mint and showed no sign of warping/misalignment. This also makes me think about the phenomenon you've brought up.

Both mine on pass side was rotated, hardly from filling oil mate. Coming apart by gentle touch. No way this is a proper design/material.

Helmsman wrote

Both mine on pass side was rotated, hardly from filling oil mate. Coming apart by gentle touch. No way this is a proper design/material.

Interesting. But was your passenger side vanos cover cracked or just rotated? In Sweden is your passenger side the U.S. driver's side?

DrFerry wrote

Interesting. But was your passenger side vanos cover cracked or just rotated? In Sweden is your passenger side the U.S. driver's side?

Every car made for the European Market (except for the UK) is left hand drive just like in the US.

Helmsman wrote

Both mine on pass side was rotated, hardly from filling oil mate. Coming apart by gentle touch. No way this is a proper design/material.

Welp... that debunks my thinking. Then I would go back to the drawing board of aged plastic.

DIY and photos coming!
Very straightforward guys…just tedious.

DrFerry wrote

Interesting. But was your passenger side vanos cover cracked or just rotated? In Sweden is your passenger side the U.S. driver's side?

Just slightly rotated and deformed. Yes we're driving on the same side...