Driving with 1 broken head stud

[roadster49]

Thanks Walt. Cole, and Bruce.
One of the things I really appreciate about owning a Porsche is the caliber of people that you meet like this or in the PCA clubs. Where else do you find technically astute willing to help folks like this.

Well I ordered Wayne's book. I have rebuilt Ford engines, and think I will attempt this. I am inclined to go with the Supertec studs based upon recommendations I have read in this media. I also read ARP are also excellent. Are studs throw away? I mean if I do a top end rebuild and in a few years do the bottom can I reuse the studs? if not it may make sense to do top and bottom now. any recommendations Please.

What I am apprehensive about is that I bought this car 2 months ago and I don't know how long the PO drove it like this. I suppose once I start the disassembly I will get a better feeling about the magnitude of the rebuild.

As you suggested, read the book, get a plan to move forward.

Thanks again.

Michael

[Walt Fricke]

Studs are not like rod bolts, which are generally a one time use fastener. If studs get damaged somehow, then you'd want to replace them. And in this case you are looking to upgrade to a stud which should last a lot longer than the original studs.

[NEWFIE 69 911E]

Originally Posted by cole930

Davy,

Here is something you might consider trying. I have a 930 and have had it for over 20 years. Over that period of time I have had a few studs break. I was actually standing the garage one winter, the car had not been driven for a few months, I heard a sharp "Ping" and heard something bounce across the garage floor. #4 bottom stud broke while sitting.

I jacked the car up a couple weeks later and took a look. Stud broke up toward the nut. I took a dremel and cutting wheel and cut the stud off a couple inches above the case, then for the next week I squirted PB Blaster on the stud at the case. On the weekend, using the broken portion of the stud I had cut off, I found that a 5/16 - 1/4 in. drive - 6 point socket would almost slip onto the stud. Using a couple long 1/4" drive extensions, I stuck the extensions through the head and then put the socket between the bottom of the head and the broken stud and popped the socket onto the extension. With the socket now sitting on top the stud I took a hammer a tapped the socket down over the broken stud. Once I had driven the socket down as far as I could I used a heat gun on high for about 15 min. to heat the case at the stud boss. I put a wimpy little 1/4 drive breaker bar on the extension at the top and backed the stud out like it was butter. I thought I was just lucky but have actually used this method 3-4 times in the last 6-7 years. Always after I installed a new stud and torqued them I never had a problem. All these broken studs and replacements have been in the past 7 years or so. In Nov. I tore the top end off the motor to replace head studs and redo gaskets to seal up the usual leaks we get. The heads, pistons, valves, and cylinders looked fine and all the replacements studs were still fine.

Not what I would necessarily recommend as a preferred practice but It worked fine for me for several years.

Cole

Excellent work! Do you have any pictures? Is there anything different about a 911 engine that wold prevent this from working (i.e. engine tin) compared to your 930?

[pharlap71]

I recently bought a '84 Carrera, while doing a clutch job and adjusting valves found a broken head stud very simular to the one pictured earlier. Being a cheapo and lazy I thought I would replace the ONE broken one (#4). I removed required stuff, slid cylinder up enough to very slowly about a tenth of a turn at a time with heat on the case to get it out and replace it.
While doing other tasks and getting ready to install engine I heard the infamous and dreaded "PING", yep, another one let go. I did a little research, you know, stock, oem, Raceware, ARP, etc. After talking to Henry Smidt on the phone I decided on the SUPERTEC, the only one with a warranty. I have no regrets, excellent product and concidering you get new nuts and washers not a whole loy more than steel.
So my advice is bite the bullet and don't do like me and do it twice. You can be careful and slide the cylinders up and remove wrist pin clips and remove pistons in their cylinders. Plus you can really get a good look around and see the condition of things. I lapped my heads when re-installing, I know every one doesn't but I guess I am old school.