Valve Cover Gasket Change!

This is all the silicone RTV I used. I wasn't going to use any until I saw that seam.

Originally Posted by SF323Ci

Took two total noobs being extra careful about 8 hours, including lunch, two trips to the hardware store, a trip to the dealership, and fishing out the negative terminal retaining bolt out from under the battery..
We could probably do it again in two hours or less.

Originally Posted by mkodama

A day if you are going at a relaxing pace. If you know what you are doing and have a nice tooling setup, less than 20 minutes could probably be done.

Thanks for the info guys!

This makes me excited to do it Thanks a ton!

My gasket was VERY brittle. I used a heat gun to speed up the removal process - it worked wonders.

I was surprised when I changed out mine at 70,000 miles. The old gasket was still soft and pliable. Unusual due to the heat we experience here in Arizona!

Originally Posted by klax

I was surprised when I changed out mine at 70,000 miles. The old gasket was still soft and pliable. Unusual due to the heat we experience here in Arizona!

Could be your location constant temperature, as opposed to freezing/thawing that we get in New England.

I actually lived for several years in Prescott, AZ with this car before Phoenix. Prescott easily gets down into the teens and twenties in the winter time and upper nineties in the summer. I don't think that's it.

I think prolonged idling is the worst thing you can do to a car and I avoid it as much as I can. In the Porsche 996 owners manual, for example, it states clearly "avoid prolonged idling". These engines run hot anyway and sitting there with the engine running (drive-through window, etc), your under hood temperatures will skyrocket.

My next door neighbor has an e46, and, like me, has owned it since new. I notice that the rubber "eyebrows" over his headlight lenses are brittle, cracked and falling apart. Mine, like the valve cover gasket was, are soft and pliable.

Just lucky, I guess.

Wow, 16 pages and nobody posted a link to the BavAuto DIY? (Not that it's any better, but it does address the whole "sealant at the half moon" issue - on step 12; Figure 10.
http://blog.bavauto.com/643/replacin...t-on-your-bmw/

They use this stuff -
http://www.permatex.com/products/aut...t_Dressing.htm

Personally, I think they put too much of the sealant on, and I'll likely reduce the amount by 30%

Schnell

Originally Posted by mach.schnell

Wow, 16 pages and nobody posted a link to the BavAuto DIY? (Not that it's any better, but it does address the whole "sealant at the half moon" issue - on step 12; Figure 10.
http://blog.bavauto.com/643/replacin...t-on-your-bmw/

They use this stuff -
http://www.permatex.com/products/aut...t_Dressing.htm

Personally, I think they put too much of the sealant on, and I'll likely reduce the amount by 30%

Schnell

Damn that's a lot of sealant!

I'd much rather trust the BMW recommendation of a small amount on the sharp corners of the head, and not applying the sealant directly to the gaskets in such large quantities. That's just asking for a needless mess.

I am doing this tomorrow evening after work and I bought some vanos line seals as well. When they came I got metal rings. I don't know the first thing about the vanos, but is that what they are supposed to be?

Originally Posted by association16

I don't know the first thing about the vanos, ...

Well then you'd better do some reading here: http://www.beisansystems.com/

A part number would be somewhat helpful don't you think? But I have the feeling the "metal rings" you have are the VANOS oil line crush washers.

#17 on this diagram:

http://www.realoem.com/bmw/showparts...70&hg=11&fg=15

Unless you remove the VANOS oil line feed, these aren't necessary. And it isn't necessary to remove the VANOS oil line feed to replace the Valve Cover Gasket.

BUT... you might want to keep them on hand for when you find out you need to replace the oil filter housing gasket (where the housing attaches to the engine).

Originally Posted by mkodama

Damn that's a lot of sealant!

I'd much rather trust the BMW recommendation of a small amount on the sharp corners of the head, and not applying the sealant directly to the gaskets in such large quantities. That's just asking for a needless mess.

Technically the product is not a sealant, so - sorry if I misspoke. It is a Rubber Gasket Dressing, and cannot be used for RTV applications. In other words, it can't be used to create a gasket, which is what RTV is designed for.

I've read a lot of threads on the Drei Bond 1209, and interestingly enough, Google tends to return a lot of threads from the BMW motorcycle community. All this type of product, hondabond, yamabond, etc... and the Drei Bond 1209 are Gasket formation products - used to create a gasket between two halves of a metal casing.

Here, though, you already have a gasket. You don't need to make one. Rather you need to make sure whatever goo you use is compatible with rubber, and in this case, also with plastic. Some of the silicone sealants cure with vinegar - not so "compatible" with rubber. I provided the link above, and you can read for yourself whether this is better than the magic Drei Bond.

Given the Bentley Manual was written 10 years ago, and that materials engineering has quite progressed since that time, The Permatex Dressing is much more applicable to the Valve Cover Gasket (a rubber product) than any RTV or its supposed equivalent. The Dressing was designed to plug those odd corners in a rubber gasket that might leave a microscopic leak if there were any minor torsions during installation. It does not dry like RTV, and so remains flexible with the rubber. I have the feeling Permatex wants mechanics to use this product rather than spending the time to clean the metal surfaces. But that's another conversation.

The purpose isn't to make a gasket (like RTV) but to plug up any minute holes that might arise from the gasket being incorrectly seated. It's perfect for those half moons.

The "BMW recommendation" was made ten years ago, when mystery Drei Bond was actually available, and a rubber dressing didn't exist. Quite a number of posts mention that Drei Bond and its "equivalents" would dry out faster (meaning a gasket made with such RTVs would need replacing more often than a standard replacement gasket).

I've also seen quite a number of posts that show the VCG leaking at those corners even when RTV product was used. The Permatex rubber gasket dressing doesn't dry out. (I know - just don't ask.)

That said, is it better to place the dressing on the metal? Or on the rubber?

I agree, that BavAuto used more goo than I think is necessary, and I am temped to put the goo on the metal, just so it doesn't get all over anything else as one seats the valve cover into position.

Mach

Did my valve cover gasket today. Car is around 100k miles. The gasket is really brittle. The engine looks fine. Happy motoring~

Originally Posted by mach.schnell

I've also seen quite a number of posts that show the VCG leaking at those corners even when RTV product was used.

Thank you for the breakdown on this sealant. I have to say the rtv did not work well for me. I still get a whiff of engine oil burning after a long drive. I tried it with silicone on the head all around the half moons; and then I tried it again with just the tiniest bit at the seam where the vanos housing meets the head. I even replaced the valve cover. Each time I pulled the cover off, I noticed the RTV and the rubber gasket just weren't very bonded. I think the RTV did it's own thing at temperature, and the rubber gasket did another. I used to work in a shop that used trim adhesive (yellow snot) on gaskets. It was a rubber glue now I'm sure. Not silicone.

Originally Posted by karatechop5000

Thank you for the breakdown on this sealant.

You're quite welcome, but I'll send the thanks on to my wife the materials engineer. Don't ask why but she's more into texture, temperature, adhesion, solvents, than shoes, jewelry and handbags.

The rubber gasket BMW used was designed to seal the plastic valve cover to the metal head. The next question is what kind of plastic and what kind of metal (and what kind of rubber). Most of the machined parts are aluminum, and certain corrosion patterns seem to indicate some parts are bonded with magnesium.

She's puzzled that everyone recommends Simple Green to clean grease off metal parts, since (I forget which component) reacts with aluminum and causes pitting. So she'd rather I actually use CRC throttle body cleaner than even the recommended brake cleaner in the VANOS project (except on the actual seals). So I'm backing up a few steps, and with the VANOS in pieces (and before the new seals are installed) will clean everything off with throttle body cleaner first.

Engineers - gotta luv em.



(Hey, want insight into the German engineering mind? Go watch some Schuhplattler dancing. Just remember these are the people who designed the CCV )

Originally Posted by mach.schnell

you're quite welcome, but i'll send the thanks on to my wife the materials engineer. Don't ask why but she's more into texture, temperature, adhesion, solvents, than shoes, jewelry and handbags.

The rubber gasket bmw used was designed to seal the plastic valve cover to the metal head. The next question is what kind of plastic and what kind of metal (and what kind of rubber). Most of the machined parts are aluminum, and certain corrosion patterns seem to indicate some parts are bonded with magnesium.

She's puzzled that everyone recommends simple green to clean grease off metal parts, since (i forget which component) reacts with aluminum and causes pitting. So she'd rather i actually use crc throttle body cleaner than even the recommended brake cleaner in the vanos project (except on the actual seals). So i'm backing up a few steps, and with the vanos in pieces (and before the new seals are installed) will clean everything off with throttle body cleaner first.

Engineers - gotta luv em.



(hey, want insight into the german engineering mind? Go watch some schuhplattler dancing

just remember these are the people who designed the ccv )

rofl...lamo

BTW the brittle VCG rubber that's hard and cracks like plastic will soften up to a bendable taffy like consistency over a two or three day period in damp weather.

So whats the consensus on the sealant/rtv/glue/cement/magic putty we should be using on the half-moons?

Originally Posted by Rubenk

So whats the consensus on the sealant/rtv/glue/cement/magic putty we should be using on the half-moons?

You mean does BavAuto have the experience to be right? Once the VANOS is done and I put the VCG back on, I'll let you know.