Broken head stud question. Advice sought.

[rs6er]

I finally got up the courage to do my own valve adjustment with some help from Johnnyo. When we removed the lower valve covers we found 3 broken studs on the left and 4 on the right. All were the top studs. On the left side there is one broken one on each cylinder. On the right, one is broken on each cylinder except for #6 which has 2 broken. I've already done a search on broken head studs, but I have a few questions. Bear with my lack of knowledge. I assume that the motor has to come out to fix this condition. Right? Is it possible for an individual to repair these or does it have to be done by a machine shop? I've seen estimates in posts for this kind of work. 3000-4000. Does this include other work or just replacing the studs? Is it okay to drive like this? If so how much? Any advice would be appreciated.

This all started with me replacing my exhaust system. The old one had rusted exchangers and a completely rusted out cat bypass pipe that was quite loud. So any questions about noise are irrelevent.

Also, Johnyo just bought a 3.6 that he's putting into his car, and he has a 3.2 I could put in instead. Is this a worthwhile upgrade to my basically stock 3.0?

[anthony]

The $4000 figure I'm sure is an upper end valve job plus new studs.

There have been users here that have done this job themselves. It just depends on whether you were comfortable tearing into your engine by yourself.

[scottb]

A Pelican by the name of "A Quiet Boom" has developed a REALLY slick tool for drilling out broken head studs. From what I understand, you can do the work while the engine is in the car. For that number of studs, however, it probably would be easier to do an engine drop.

Here's a thread discussing A Quiet Boom's tool.

Good luck!

[rs6er]

If you are talking about Chris's tool. I am a devoted user. I just used it to replace all of my exhaust studs. However, I am now talking about cylinder head studs— the ones inside the valve covers.

[scottb]

You're right. My bad. Sorry.

[john walker's workshop]

you pulled the lower covers off, found several broken studs and you said all the broken studs were the top ones. doesn't quite make sense. top ones are under the top covers, and they're steel and don't break.

[rs6er]

The studs that broke are inside the lower valve covers. They are the ones with barrel nuts and thick washers placed along the top of the head inside the deep holes not the ones that are lower down on the heads. Maybe the lower ones (the ones with the hex nuts) are not head studs at all? I thought there were 4 studs per cylinder. Also the broken ones are dilivar and don't respond to a magnet.

[rs6er]

Here is a picture of the broken studs:

[Joe Bob]

BTDT.....engine pull and top end rebuild...do the valves while yer in there. Consider upgrading the cams as well as the ramps and chains.

[Doug E]

7 ??? Wow, when I found my 3 I thought that was a bad day.

[john walker's workshop]

the short pieces mean there's still something to grab, to get the rest of it out of the case. the long ones are another story. best to leave those to a professional. don't try to get the 1/8" stubs out unless you're real handy, or you will just make the job harder for the pro. sometimes they have to be electrically vaporized.

[rs6er]

Originally posted by john walker's workshop
the short pieces mean there's still something to grab, to get the rest of it out of the case. the long ones are another story. best to leave those to a professional. don't try to get the 1/8" stubs out unless you're real handy, or you will just make the job harder for the pro. sometimes they have to be electrically vaporized.

John-
I've never heard that term before. How do you electrically vaporize them?

[Joe Bob]

EDS...electrodeposition or something like that...electric arc burns the stud out.

[rs6er]

Where do you get that done?

[ianc]

There is a process called EDM that can be used to remove them if there's nothing left of them. If there is something left sticking out, you may be able to weld something on to the end of the stud and get them out that way. Do not try drilling them out. You'll probably need to heat the case in the area where the stud goes in to get them out. Propane should be sufficient for this.

The engine definitely needs to come out for this. Depending on how much experience you have and if you can stand the downtime and expense, it's a good time to replace all the studs, get new guides and valves, check valve springs, have valve seats cut, and take a look at the pistons and cylinders. Rings would probably be a good idea as well as cleaning everything and changing all the gaskets you can find.

A lot of work. I just did this job and it took me about two weeks. The worst part was cleaning everything. I probably spent $3-3.5K in parts and labor for the heads.

Good luck,

ianc

ianc

[2.7RACER]

John,
Your big moment has come. Your 3.0 is a great motor. Time, inclination for the work, and of course space for the work will decide what direction you may go.
Perhaps your friend can help if you decide to install his 3.2. If it is reasonably fresh you'll like the performance of the 3.2.
Then you have a choice of what to do with your 3.0.
It is probably worth $2-2.5k complete as it is.
If you have have the time and inclination rebuilding the 3.0 can be a very satisfying experience. Likely cost $2-4k not counting your time.
If you can sell your 3.0 and get the 3.2 for around $5k looks like a wash for cash outlay. Time now that's a big difference.
Sorry about the studs.

[tsuter]

Yeah those long ones...fun. If you don't have at least a 1/4" that you can grab good with vice grips....fuugetaboutit!!

And if they have timeserts already....you are really pooched!

I used to work with an EDM (Electrical discharge machining) shop in Chicago. We can use a matched electrode to machine those out. Non contact machining. The spark from the electrode does the job while the workpiece is submerged in dielectric oil.

Lots of fun but slow.

The good news is that 20 years ago there was probably only 1-2 shops in Torrance, CA that could do this.
Now there are a lot...all over.


But you have to drop the motor.

[JBO]

Don't continue to drive it with that many broken. If you keep the 3.0, have the cams reground to 964 specs (Pelican "camgrinder" did mine). If car is otherwise in good shape, from what I have seen in the market you would be better off rebuilding yours than putting in the 3.2. It may not be logical, but many buyers like originality and don't seem to like the idea of a different (even if better) engine than what came in the car. I was like that myself as a greenhorn - now I'd look for an SC with a 3.6

[rs6er]

Doug-
This happened as I was about to try your method! Just to be clear, there is no way the head can be removed without pulling the motor?

[john walker's workshop]

that's a big N.O.