Subject: Stud Removal

From: [email-masked] (Joseph M. Krzeszewski)
Date: 5 May 1996 02:51:43 GMT

Greetings all,

I need some advice on a project I am about to undertake.

Now that the New England weather has warmed up a bit I am doing all those
repairs on my car that I put off all winter. Among those repairs is
replacing the studs that hold the exhaust system to the cylinder heads of my
1972 air cooled VW. I broke one of them off in February, and they are all in
fairly bad shape. Given that all the studs are very rusty and banged up, I
am replacing them all. 

Now, here are the questions....

1) How should I remove the intact studs (steel studs - Al head)?
   a) brute force
   b) heat and brute force
   c) chemicals and brute force
   d) etc...

2) How should I go about removing the broken stud (broke flush with head)?

I may be way off base here, but could the fact that it was about 30 degrees
out when I was working on this last be responsible for shearing the stud?

BTW, in case anyone is interested, I took the broken stud down to the lab
and performed a microstructural analysis. Very poor materials. The stel had
been spheroidized to make cutting the threads easier, but not heat treated
after. I wonder if these are the original VW parts...

-- Joe

--
Joseph M. Krzeszewski		Mechanical Engineering / Materials Science
N5LHF          			 Jack of All Trades, Master of None... Yet
[email-masked]   		-= CCC Shop Student Hardware Specialist =-

---

From: [email-masked] (John W. Hall)
Date: Sat, 11 May 96 14:17:51 GMT

In article <[email-masked]>, [email-masked] (Glen Goens) wrote:
>Joseph M. Krzeszewski ([email-masked]) wrote:
>: Greetings all,
>
>: I need some advice on a project I am about to undertake.
>
>: Now that the New England weather has warmed up a bit I am doing all those
>: repairs on my car that I put off all winter. Among those repairs is
>: replacing the studs that hold the exhaust system to the cylinder heads of 
my
>: 1972 air cooled VW. I broke one of them off in February, and they are all 
in
>: fairly bad shape. Given that all the studs are very rusty and banged up, I
>: am replacing them all. 
>
>Been there.  Done that. :-)
>
>I would recommend that you soak the intact studs liberally with a 
penetrating
>oil and then heat the flange with a heat gun or propane torch, clamp a pair
>of vise-grips on the stud and torque away.  For the broken stud you can try
>using a drill and an easy-out in combination with the above tactic.  If all
>else fails, drill the studs out and retap the holes for the next nearest 
>thread size, you can probably replace the metric studs with an SAE thread
>stud unless you're using a strange muffler setup.
>
>Hope this helps
>
>Glenn Goens -- [email-masked]
>
>P.S. Don't forget to use an anti-seize compound on the new studs.
>
>
I have newer had any luck with easy outs. I think its because to get one 
beefy enough to turn the stud, the drilled hole leaves such a thin wall of 
the stud that the easy out actually forces the stud tighter in the hole. 
	I've never done it but I remember hearing that VW engins come out in 
about twenty minutes, so I would do that, and set up the thing so I could 
drill the studs out on a press or mill and then chase out the holes. I 
shouldn't think a little mis alignment of the new studs would matter to the 
manifold. 
	If you were working on a cast iron block you could just blow the stud 
out with a cutting torch. That has always been the most successful technique 
for me. Brutal though it sounds it works like a charm 'cause the steel stud 
burns up and leaves the bare casting.

John

---

From: [email-masked] (Steve Rayner)
Date: Sun, 12 May 1996 11:30:44 GMT

In a previous article, [email-masked] (Warren Palmer) says:

>u.ca!usenet
>From: Warren Palmer <[email-masked]>
>Newsgroups: rec.crafts.metalworking
>Subject: Re: Stud Removal
>Date: 10 May 1996 16:57:46 GMT
>Organization: Assiniboine Community College
>Lines: 15
>Message-ID: <[email-masked]>
>References: <[email-masked]> <[email-masked]>
>NNTP-Posting-Host: net2apc23.assiniboinec.mb.ca
>Mime-Version: 1.0
>Content-Type: text/plain; charset=us-ascii
>Content-Transfer-Encoding: 7bit
>X-Mailer: Mozilla 1.1N (Windows; I; 16bit)
>

Unfortunately, I remember some cylinder heads with cast in studs.  These
must be drilled out.  A helicoil makes the job much stronger, as the heads
are soft cast aluminum.

>
>On many occasions I have been able to remove the stud by heating it with 
>a torch and then drilling it out (slightly under the tap drill size) 
>using a left-hand drill. Often the left-hand drill will unscrew the stud 
>as it drills.
>-- 
>~~~~~~~~~~~~~~~~~~~~~~~~~~
>Warren Palmer     
>Machine Shop Instructor
>Assiniboine Community College
>Brandon, Manitoba, Canada
>([email-masked])
>~~~~~~~~~~~~~~~~~~~~~~~~~~
>
>
>

-- 
************************************************************************
     MY SECRET IS OIL OF HARLEY DAVIDSON !      Steve Rayner
************************************************************************

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From: [email-masked] (Joseph M. Krzeszewski)
Date: 12 May 1996 20:10:08 GMT

First of all I would like to thank everyone who replied to my post. This
includes email replies as well. Thank you.

I got the engine out of the car and much to my surprise the stud in question
was not broken off flush with the head. There was about 1/4 inch of stud
hanging out. Vice Grips didn't move the stud, so off came the head.

I wandered down to the school shop and we tried heating the aluminum and
then turning the stud out. No good.

I ended up center punching the stud and drilling it out. I followed up with
a tap and put in a new stud.

In article <[email-masked]>,
>must be drilled out.  A helicoil makes the job much stronger, as the heads

I must have one of these heads... I litterally cut threads across some of
the old threads that were still filled with steel from the stud... The steel
remained fused to the aluminum. I am going to assume that if the tap didn't
dislodge the stud, neither will normal use.

Now if I can just find someone to loan me a floor jack I can put the engine
back in to car....

-- Joe

---

From: Bill McJunkin <[email-masked]>
Date: Wed, 15 May 1996 21:09:25 -0700

Bill Webster wrote:
> 
> In article <[email-masked]>, [email-masked]
> (Jonathan M. Elson) wrote:
> 
> > : replacing the studs that hold the exhaust system to the cylinder heads of my
> > : 1972 air cooled VW. I broke one of them off in February, and they are all in
> > Others have given some help in removing the studs.  But before you install
> > new studs, get a can of anti-seize.  It is a mixture of oil and metal
> > particles.  It looks like powdered aluminum and copper turned into goo.
> > But it works.  I use it on anything connected to exhaust systems, and
> > anything involving steel bolted into aluminum where heat or stress is
> > involved.  I use it on all manifolds, head bolts, spark plugs, etc.
> > I've never had a problem removing something after I used the anti-seize.
> 
> Anti-seize does work well, but, be sure to buy the type which isn't
> effected by heat.  This stuff is available in different heat ranges and
> for various chemical environments.
> 
> My neighbor put anti-seize on spark plugs and 2 out of the 6 seized!
> Turns out that there are different heat ranges for this stuff.  We talked
> to a couple of car mechanics and they said never put anti-seize on spark
> plugs.  There's simply too much heat and the anti-seize turns into a
> glue.  They said they do a fair amount of business removing plugs that
> have seized from anti-seize.
> 
> Well, I've never used the stuff on spark plugs, but I have used it on
> studs (other than those found on exhaust manifolds).  Works great.
> 
> Your mileage may vary.
> 
> regards.
> 
> --
> Bill Webster   [email-masked] you want high temp protection and anti seize/anti galling protection 
use 'NEVER-SEEZ'.. it is (I think) the origional anti seize compound.  It 
is now made by the same company that makes LOCTITE.... It is good to 
2,000 F. It was first used to install pre-combustion chambers inside 
diesel cylinder heads (in the combustion chamber).  I have used it in 
steam, acids, lye and under water/mud etc, IT WORKS!   I use it on spark 
plugs and have never had a problem. Just remember to reduce the 
tightening torque by 10% so you don't break the stud or split a casting. 
  
-- 
Bill