Broken Head Studs

[FL911]

What was supposed to be an exhaust upgrade and valve adjustment has took a turn for the worse! I pulled the driver side valve cover and 3 of my head studs basically fell out on the floor. Not Cool!
I am hoping I can receive some good info from my Pelican brothers and sisters on what I need to purchase other than the head studs in order to repair this. I know the engine needs to be dropped which sucks but I have to look at this in a possitive way and get it done!

- What kind of studs do I buy? This is just a stock 1981 911SC 3.0 liter, so can I just get the steel stud kit through this site or should the ARP's or Supertec's be used

- Additional gaskets? I am sure there is a lot of these to buy.

Any tips on engine removal?

I am bummed!!!!

[anthony 911]

what part of mo do you live in?

[FL911]

Near Troy, MO
Are you familiar with that area?

[anthony 911]

yes ..im in imperial mo...

[Grady Clay]

Don’t be bummed, look at this as an opportunity to do some useful long-term maintenance and some fun things.

Dropping the engine and transmission on a 911 is outrageously easy compared to most cars of similar ilk.

The opportunity for fun things is almost endless, limited only by a sane budget.

Now is the time to replace seals, gaskets, O-rings that become accessible with this operation. You might consider having a ‘better-than-Factory’ valve job. You should inspect the clutch and (at least) replace the disc. You will want to replace the six chain ramps and rebuild the tensioners (cheep insurance).

Before you do anything, perform some diagnostics. I recommend a cranking compression test, a cylinder leak test, cut apart the oil filter, inspect the transmission drain plug and the shift plate. Inspect for other oil leaks.

You want to identify any other potential or actual problems. If you are going to the effort to take the engine down to the assembled case, you don’t want to miss any opportunity.

Be sure to add some fun.

Best,
Grady

[anthony 911]

looks like ..rings -valve guides-seals-stds-ect......

[FL911]

Thanks Anthony and Grady.....I know it will be an enjoyable learning experience but I did not want to nor have the extra $ to do this now. Oh well what the _ell, it has to be done so why not know right?
Anthony, I go to I-55 Raceway and watch the dirt trackers pretty often during the summertime!

[anthony 911]

5 min from me..

[cole930]

I keep loosing my text before I get finished with my reply. Give me a call I
think I can help without removing the engine.

Cole930
260-570-6914

[yelcab1]

I recently replaced all 12 lower head studs to steel ones when I (for fun) did a valve job on the 80SC. The job was done with the engine out of the car on a stand, heads removed but not the cylinders, MAPP gas torch left burning at the base of the stud for 5 minutes, a borrowed Snap On stud remover and a stud installer (a very neat thing, NLA). Took all of 1 hour.

On the way back in, all the chains and cam sprocket were replaced, some out of spec rocker arms replaced, valves timed and adjusted. The new valve job gives the car a new sexy tight turbine sound, good throttle response. You may want to do the same, or not.

[FL911]

Cole I may be calling you.
yelcab1 - all of your head studs must have been in one piece in order to do what you did.
Mine are broken off down in the cylinder hole. So I am going to have to (unfortunately) remove the actual cylinders to get to the broken studs.
What brand of steel head studs did you use?
I do not have a race engine, just stock....and I want to use an adequate head stud replacement but was not planning on spending $650 for the Supertec Kit even though I may have to.

[72 four door]

Have you checked the other side? Use the steel studs,and prepare to do the, while your in there stuff. How many miles on the motor? Repace the rear seal too and check the clutch. It does get pricey but while its out its a no brainer.

[FL911]

No, I have not tore into the passengers side yet, I am sure more are broken over there.
The motor only has 94K on it and runs great, no smoke at all. Just has some common oil leaks.
I have read that the exhaust side seems to be the ones that break are these the "Dilavar" studs? I guess this is due to the expansion differences in the dilavar compared to the steel studs?
I will prob. go with the $450 steel stud kit , is that what you are referring to? The OEM replacement studs.

[anthony 911]

go with the supertec or the raceware..when your in there do the heads..ect...

[914efi]

I did this last winter as a repair rather than a big budget upgrade. Take off heads ( I removed all heads and cam hsg together), slide cyls out far enough to remove wrist pins (heat pistons with heat gun, they will slide out) and remove without taking pistons out of bores. Decide how to remove studs ( I MIG welded nuts on and used the MIG to heat the stud by laying a bead near the base if it was long).

Clean stud hole, I ground flutes into a stud and chased threads with it so as not to cut more than needed. I used basic steel studs, nothing fancy.

Then reassemble and have fun. I would say the whole thing was under a grand.

[Superman]

Absolutely no need to use expensive, fancy studs. Use regular factory steel studs. Used ones, if you can find them cheap. They don't break. These are the studs on the intake side of your engine. The unreliable Dilivar ones are on the exhaust side. So.....you only need twelve of them. You will have to remove the cylinders and use HEAT (much more than propane heat) to get the red loctite to let go of the studs. Do a Search and read. Chase the threads and use red loctite to install the new ones to the proper height.

You'll have the heads, pistons and cylinders off the engine. You'll have those parts on the bench and all that's left is a case with rods poking out. At a minimum, I would take the rods off and replace the rod bearings. In reality, I would split the case and replace the main bearings also. And inspect the oil pump and crank. At this point, all the parts that should be at least measured in a full rebuild will be on your bench. Do this. Take them to a machine shop and have them measured, reconditioned, magnafluxed or all three. The rod big ends can be machined as new, and I would do this. The wrist pin bushings can be replaced, and I would do this too. The valves should be measured and if their shafts are too worn, replaced. Seats are ground. Guides are replaced. Yes, this will cost you some money. For me, it was about $3K. That was all new valves, guides, seals, bearings, etc.

This is the time to measure and ensure your engine internals are in good shape. If you do this, you will be building a quarter-million mile engine. It will have better valve guides than original for sure, maybe better rings and bearings. I would also have the machine shop balance those engine parts within an inch of their lives. If you do this, your engine will be pretty happy. It will spin like crazy.

[3.2 CAB]

SUPERMAN, I am still laughing at that last post. It started out, from using used studs, to becoming a money eating machine! BUT, you said exactly, how it happens. You are just going to do this one little thing, then you see this, then you think about that, and then this. It is the best chuckle I have had yet today! I thank you. Tony.

[Rot 911]

Originally Posted by FL911

Near Troy, MO
Are you familiar with that area?

If you need to borrow a 911 yoke for an engine stand, Z-block, dial indicator, etc. for the engine build, just let me know. I'm about 1 1/2 hours from you in Jeff City.

[Vincent 911]

FL911, I was exactly in the same situation 5 months ago: 5 broken head studs on my 3.0 SC.

Here is what I did:
1- Get Wayne's book.
2- Remove the engine
3- Remove everything to get acces to the studs (EFI, shroud, fan, cam towers, heads and cylinders)
4- Send my heads for a valve job (new guides, check the springs)
5- Remove the old studs: that is the most difficult task.
I ordered a stud remover tool from Snap-On and heated the block around the pistion spigot area with a torch.
For the broken studs if you are lucky enough you can thread them to 8mm and remove them with the Snap-On tool. 3 of my broken were to short to be threaded so I send the block to a specialist on Ohio who removed them (very good job for $150)
6- Clean the threads in the block
7- I replaced the 24 studs with new steel coated studs. Don't forget the new nuts & washers.
Be careful to the length
8- Reassemble cylinders, heads and cam towers.
9- Cam timing. Not so diffcult.
10- Shroud, EFI, Distributor, exhaust...
11- Put the engine back in the car
12- Enjoy it!

On my side I have made some upgrades: Carrera tensionners, 964 camshafts, SSI, RSR seals...

Good luck.

PM if you need some info on the Snap On tools. It worked realy well.

[72 four door]

Yes use the regular steel studs,as superman said i dont know if i would go used,[thats pushin it] Change the stuff you cant reach when its in there.if its not smokin do the studs,and call it a day. Mine had 2 broken studs w/only 90000 miles i ended up doing the whole engine just for peace of mind. Take pics and go slowly.