Valve cover gasket DIY

BzsBimmer wrote

Did they coat the new covers differently? They look more grey than tan

The new OEM covers seem to have a slightly darker grey than the original ones, but the original ones I had were never tan. The tan you mention may be due to discoloration.

Shredicus wrote

What's the consensus about recoating the interior of the covers? Is the magnesium reactive internally? Why did they coat them in the first place?

The OEM covers are coated on the inside as well but not as nicely as the tops. I got the replacement covers at a good price and was weary about getting the OEM ones refinished. Being magnesium alloy, I was unable to find a definitive answer on what the proper method for refinishing was. I did reach out to Dinan because they recoat their stroker valve covers black but got no response. Now that the car is done I'll look more into refinishing the old covers to have as spares or to sell.

It is my understanding that the magnesium alloy will corrode if exposed to moisture (e.g., humid air) and should be coated.

Shredicus wrote

Maybe that tan comes from normal varnish on the inside and heat embrittlement/yellowing on the outside? When I need to do this I'm definitely getting my covers media blasted and powder coated.

What's the consensus about recoating the interior of the covers? Is the magnesium reactive internally? Why did they coat them in the first place?

they paint it...
i had mine refinished out came out great.. think about Dinan when they powder coat stroker covers black...

I like the paint idea but my opinion is that the black cover gets lost in the sea of existing black. I think if you're going to paint it, a contrasting color would showcase the motor a bit more.
Red would be cool but the factory gray works too. Just my $0.02

rantarM3 wrote

The new OEM covers seem to have a slightly darker grey than the original ones, but the original ones I had were never tan. The tan you mention may be due to discoloration.

You're right. I'm thinking of the crap that is inside the cover. That stuff is a tannish color

Cbozz wrote

they paint it...
i had mine refinished out came out great.. think about Dinan when they powder coat stroker covers black...

They look quite nicely done. Could you please PM me the info on the shop that did the powder coating for you? Much appreciated!

BzsBimmer wrote

I like the paint idea but my opinion is that the black cover gets lost in the sea of existing black. I think if you're going to paint it, a contrasting color would showcase the motor a bit more.
Red would be cool but the factory gray works too. Just my $0.02

I thought of painting it satin red, that was my other option but then I thought of it and left red for ferrari and satin black looks pretty clean and didn't think that really matters anyway since I don't really see the engine much.. looks more OEM

CBozz, that looks fantastic!!!

I'll be doing a change-out of the valve cover gaskets and tubes in the next couple of weeks due to leaks on both banks at only 57K miles

Do we HAVE to replace the bolts with new ones? Those alone cost more than the gaskets and tubes combined!...can they not handle one more tightening?

GM

GMCHEM83 wrote

I'll be doing a change-out of the valve cover gaskets and tubes in the next couple of weeks due to leaks on both banks at only 57K miles

Do we HAVE to replace the bolts with new ones? Those alone cost more than the gaskets and tubes combined!...can they not handle one more tightening?

GM

You don't have to replace the screws. But, you do have to replace the seals around the screws. And those come as one part on the S65 (assembly). It's a bummer. On the S54 engine and others, the seals are available separately...

Quite the bummer! Thanks for the reply. I will certainly do it the right way, and order the new screws.

GM

JonM wrote

You don't have to replace the screws. But, you do have to replace the seals around the screws. And those come as one part on the S65 (assembly). It's a bummer. On the S54 engine and others, the seals are available separately...

http://www.roadsters.com/gibbs/

Some examples of what magnesium does when it's left un-painted


Also:

http://www.bimmerboard.com/forums/posts/541377

http://forums.pelicanparts.com/porsche-911-technical-forum/463405-my-clean-engine-fan-shroud.html

And, bare mag in a Can-Am car (believe this is a vintage racer with some years on it, modified hoop and aeroquip stuff everywherel):



Another M8 with the bare mag covers, note these covers are 35 years old in this picture, though I'm sure they get plenty of attention these cars also just sit still in storage a lot:

http://mathewscollection.com/gallery/1970-mclaren-m8d/



And because it must be posted:




Now, I'm not saying you should just strip the covers and leave them bare with just a coating of penetrant and expect them to look like brazillion dollar vintage racer that gets wiped down with baby diapers with babies still in them, but still, not like they're going to disintigrate into nothing if left bare either so long as they're coated in something durable and hydrophobic. I still think the smartest play is to replace these with new covers while they're still available. But why not noodle about it one of the things I've seen popping up in my digging around on this, because this is a fun topic because most everything that comes with mag parts on it is cool, is Dow 7, but I would worry about the coating's durability especially on the business side of the cover where hot oil would be splashing

http://www.vintageeng.com/products/magnesium-wheels/trans-am-indy/

I came to m3 forum and this thread by accident, but will say this: owning an early N52 with magnesium cover I had done some small research on magnesium corrosion and what I had read was not recommending painting magnesium. Reasoning was magnesium corrodes mostly by galvanic reaction with other metals. A scratch or pin strip on the paint will concentrate the galvanic reaction current on that small area causing holes and such. Without paint the current will be distributed to wider area. Now I am out!

PhaseP wrote

I came to m3 forum and this thread by accident, but will say this: owning an early N52 with magnesium cover I had done some small research on magnesium corrosion and what I had read was not recommending painting magnesium. Reasoning was magnesium corrodes mostly by galvanic reaction with other metals. A scratch or pin strip on the paint will concentrate the galvanic reaction current on that small area causing holes and such. Without paint the current will be distributed to wider area. Now I am out!

Isn't the OEM VC on N52's left unpainted from the factory? Or am I imagining that?

Yes they are not painted, plain ugly dull magnesium gray. My point is about galvanic corrosion, at the dissimilar metal connections such as the valve cover bolts on the cover.
"Coating the magnesium for protection against galvanic corrosion is not recommended. The reason is that coating defects are easily introduced during assembly and also during service. This defect in the coating on magnesium creates a small anodic area compared to the large cathodic area. When the coating is essential with for example automotive parts like inner door frames, robust coating systems are necessary so as to withstand the assembly forces as well as the dynamic forces during service."

http://www.magnesiumsquare.com/index.php?option=com_content&view=article&id=27&Itemid=42

Well shows how much I know about m3. Your engine valve covers are coated from factory i realized now.
I guess bmw used isolating washers on the bolts to mitigate what I was mentioning could happen. Ignore my posts on this. If the bolts had direct contact on the valve covers it could be a potential issue with paint. Not the case here.

Not contributing to the DIY other than to say this: New genuine BMW valve covers come dressed with gaskets, oil breathers, and bolts for about $1050 for the set if you can find a good sale. SEll the old ones to somebody wanting to powdercoat and you can offset that some. All you need is the Drei-Bond, spark plug tubes, and 4x cam position o-rings (13627796699)

It comes with new aluminum bolts for the breathers too, just have to reuse the cam sensor bolts or buy new if you like spending money, which you do if you bought new valvecovers.

Richbot wrote

Not contributing to the DIY other than to say this: New genuine BMW valve covers come dressed with gaskets, oil breathers, and bolts for about $1050 for the set if you can find a good sale. SEll the old ones to somebody wanting to powdercoat and you can offset that some. All you need is the Drei-Bond, spark plug tubes, and 4x cam position o-rings (13627796699)

It comes with new aluminum bolts for the breathers too, just have to reuse the cam sensor bolts or buy new if you like spending money, which you do if you bought new valvecovers.

Richbot wrote

Not contributing to the DIY other than to say this: New genuine BMW valve covers come dressed with gaskets, oil breathers, and bolts for about $1050 for the set if you can find a good sale. SEll the old ones to somebody wanting to powdercoat and you can offset that some. All you need is the Drei-Bond, spark plug tubes, and 4x cam position o-rings (13627796699)

It comes with new aluminum bolts for the breathers too, just have to reuse the cam sensor bolts or buy new if you like spending money, which you do if you bought new valvecovers.

Nice find, lots of guys buy up old valve covers for powder coat jobs. Can probably get 3-4 bills for a set of used ones.

For the camshaft sensor and exhaust breather bolts, are they really just single use? What is the risk if I re-use some of them?

And for future reference...they snap VERY easily! (My mistake since I don't have a 1/4" drive torque wrench...lesson learned). Good idea to have a few extra on hand.

I would reuse them.

Move Over wrote

Nice find, lots of guys buy up old valve covers for powder coat jobs. Can probably get 3-4 bills for a set of used ones.

IE mr Dinan for his strokers lol

Could someone critic this parts list and let me know if this is what I need? Or if i can add or subtract for the job?

1x Valve Cover Gasket Cyl 1-4 1 11127838271
1x Valve Cover Gasket Cyl 5-8 1 11127838272
8x Spark Plug Tubes (recommended due to age) 8 11127835170
2x Collar Screws M6: 11127841218
24x Collar Screws M6x37.5: 11127841217
Drei Bond 1 7589062376