I cracked my Valve Cover while changing my VCG. What Now?

I finally got round to doing my big VCG + Vanos Seals + Spark plugs + Winter tyres job.

Everything went well right up to the point where I reinstalled the Valve Cover. I made the mistake of tightening one bolt all the way before I'd fitted all the others. The pressure difference between the boltholes caused the VC to crack right thru the hole nearest the C5 intake.

I was gently cranking it with my torque wrench waiting for the pop and instead I get this CRACK and saw a tiny hairline fracture appear next to the bolt I was torquing. It was very unnerving, let me tell you.

The crack itself is very thin and extends maybe an inch in towards the center of the cover. I put a very small amount of Red RTV on the inside of the cover in the hope that it would temporarily seal it to allow me to come up with a more permanent fix.

Interestingly, I drove the car for a few blocks and everything seems to work OK. I was expecting to see some CELs or error codes (do these display on the dash or do I need a special widget to read them?), but the car started and drove beautifully.

Is there anything I can do to fix it? I'd imagine it's a case of buying a whole new valve cover. Anyone know how much they go for? Maybe I'll wait a while and see if any of the sensors notice there's a leak in the valve cover...

Anyone else have this problem? I'd love to hear what you did about it

Cheers

Jan.

Originally Posted by JanSolo

I finally got round to doing my big VCG + Vanos Seals + Spark plugs + Winter tyres job.

Everything went well right up to the point where I reinstalled the Valve Cover. I made the mistake of tightening one bolt all the way before I'd fitted all the others. The pressure difference between the boltholes caused the VC to crack right thru the hole nearest the C5 intake.

I was gently cranking it with my torque wrench waiting for the pop and instead I get this CRACK and saw a tiny hairline fracture appear next to the bolt I was torquing. It was very unnerving, let me tell you.

The crack itself is very thin and extends maybe an inch in towards the center of the cover. I put a very small amount of Red RTV on the inside of the cover in the hope that it would temporarily seal it to allow me to come up with a more permanent fix.

Interestingly, I drove the car for a few blocks and everything seems to work OK. I was expecting to see some CELs or error codes (do these display on the dash or do I need a special widget to read them?), but the car started and drove beautifully.

Is there anything I can do to fix it? I'd imagine it's a case of buying a whole new valve cover. Anyone know how much they go for? Maybe I'll wait a while and see if any of the sensors notice there's a leak in the valve cover...

Anyone else have this problem? I'd love to hear what you did about it

Cheers

Jan.

You'd know if it didn't seal because the engine would be spitting and sputtering. I've never broken a valve cover but I have broken those studs (2 of them) that the cover nuts attach to. It doesn't surprise me though, like everything plastic under that hood things get brittle. unfortunately you're looking at a new cover, I wouldn't recommend trying to band-aid it. I think they run in the 220-250 range depending where you shop. I had priced out one from Bavarian Autosport for $223 IIRC, give them a call, or Turner Motorsport. Both are local to me so I don't shop anywhere else, feel free to look elsewhere too.

U r fine. Just use jb weld to fix the crack

Sent from my GT-P3113 using Bimmer App

New valve cover from discounting BMW sponsor runs around $170.

As I and Sansho said about, shop around and replace it. Remember when tightening, you're compressing a rubber VCG and a rubber grommet, if you tighten one side until torqued that'd side will become much tighter when the opposing side is torqued. Start from the middle and tighten one nut 1/2 turn, then the opposing nut 1/2 turn alternating between the two. Once those two are torqued, tighten the remaining nuts in an outward winding spiral, you want those pressures to be expelled to the outermost edge of the VC.

Hey guys, I'm still kinda of new to the forums and to 7xWDC-MSC, I did the same thing, I was changing out the VCG and as I was placing it back on, I broke two of the stud bolts(one outer bolt and the other is a center bolt), because I had tightened them too tight. Since you have replaced yours is it easy too fix and it is expensive? thanks.

Originally Posted by t3r10

Hey guys, I'm still kinda of new to the forums and to 7xWDC-MSC, I did the same thing, I was changing out the VCG and as I was placing it back on, I broke two of the stud bolts(one outer bolt and the other is a center bolt), because I had tightened them too tight. Since you have replaced yours is it easy too fix and it is expensive? thanks.

Were you able to pull out the broken portion of the bolt yet?

Originally Posted by tinman831

Were you able to pull out the broken portion of the bolt yet?

If you take your valve cover off, you can just back out the broken studs with a 10 mm socket because they have a hex head above the surface and are meant to be removable. It is needed anytime you get head work done or even to set your timing.