Extra part in the valve cover- broken head bolt

[VMAX1]

Had a leaking valve cover on drivers side bottom. When I pulled the valve cover off I found a little extra, head bolt fell out. Does the heat from the exaust create problems for this head? I have a test pipe and the gasket was baked. Cracked like dust.

[VMAX1]

Forgot. 1987 911

[Henry Schmidt]

The problem is the stud material. Dilivar is a nightmare of epic proportion.
This miserable material is responsible for more premature rebuilds than any other single item or design flaw.
Pull the engine and replace all your studs with a high quality replacement stud.
IMHO: If you use Dilivar as a replacement choice you should have your head examined.

[sixgun]

Henry is right. I have just finished replacing the ones in my 83 SC for the same reason. Use a good set of steel studs and do them all while you have it torn down that far. The factory uses loc-tite on their studs and you HAVE to use heat on the case by the threads in order to get them to let go. Forgoing heat and breaking a stud off even with the case is going to be a lot of unneccessary work as well as money spent in a machine shop. All this assumes that you are going to do the work yourself.
Take lots of pictures of everything before you break out the sandwich bags for the parts. You,ll be glad you did, later on down the road. Good luck!..............

[VMAX1]

Is there a manual that I should get that would help? My experience is limited to a clutch replaced. Is a small bottled torch enough to heat up the studs? What name of studs should I buy? Should I pull all heads and replace all of the studs? If so, how much more work to go ahead and do a complete rebuild? A lot of questions at once. Thanks to all for the advise.

[sixgun]

Actually you should have both the Bentley manual and Waynes book as a reference when opening up your engine. I have used a butane torch with good success on changing my bottom studs. Check with a magnet your top studs to see if they are steel. You will need to replace all of your remaining bottom studs with steel that are available from our host.
You will need to pull the heads in order to access the studs for removal , however you will probably only need to pull the cylinder with the broken stud to remove that unless it,s a middle cyl. Waynes book recomends not allowing the rings to come out of the cylinder when removing the piston pin. Pull it up just far enough to access the pin and clips It,s not a hard job, but it will eat up time to do it right. There is a lot of info about this process on this site from some very skilled and knowledgable folks and they are very helpful when we run into obstacles from time to time. Don,t be afraid to ask questions........
Best of luck........ George

[sixgun]

Hello again VMAX1,
You did,nt say what you have for milage on your engine, I,m assuming that if you have replaced your clutch already it,s high?.........

[VMAX1]

tearing down that far, is it advisable to replace the rings without cylinder work? have 130k miles on engine.

[sixgun]

VMAX1,
Do a compression check on it before you go any further. That will tell you a lot. Some of these engines go 250,000 + miles and still run good. Changing the oil often is the single most important thing you can do to prolong TBO..........
George
83 911SC