Welcome to the The Garage Journal Board forums.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   The Garage Journal Board > The Tools > Fabrication & Techniques

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Search this Thread Display Modes
Old 08-22-2011, 11:21 PM   #1
JeepsAreBuilt
Senior Member
 
Join Date: Nov 2006
Location: The Beautiful NorthWest
Posts: 757
Default removing exhaust manifold stud tricks ?

I got an almost 50 year old exhaust manifold I want to replace the studs in them as its going on my CJ5 motor. Heres what I'm working with:



Any good tricks ? I dont want to drill it out and tap. I thought of welding a nut on the stud and use my impact to back it out. Would heating up the cast iron manifold help any ?
JeepsAreBuilt is offline   Reply With Quote
Old 08-22-2011, 11:36 PM   #2
Jeff Ivers
Senior Member
 
Join Date: Apr 2010
Location: Oklahoma
Posts: 558
Default Re: removing exhaust manifold stud tricks ?

I would use lots of Kroil and either double nuts or a stud extractor. Unless someone more knowledgeable advises it is ok, I would avoid heating the manifold for fear of warping it.
Jeff Ivers is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 08-22-2011, 11:43 PM   #3
blacK20
Senior Member
 
Join Date: Mar 2011
Posts: 636
Default Re: removing exhaust manifold stud tricks ?

A stud extractor with a little bit of heat(not red hot) will take them right out. I would not worry too much about warping the manifold. The only area that you really do not want warped are the flanges that mount to the head, and that is far away from where you need to heat.
blacK20 is offline   Reply With Quote
Old 08-22-2011, 11:46 PM   #4
toolfreak
Senior Member
 
Join Date: Jan 2006
Location: Illinois
Posts: 1,268
Default Re: removing exhaust manifold stud tricks ?

I would heat it up and use wax. Try to get it to come out with vice grips. Once it starts to unscrew, you may have to reheat and reapply the wax.
toolfreak is offline   Reply With Quote
Old 08-23-2011, 12:46 AM   #5
vpd66
Member
 
Join Date: Mar 2010
Location: Central Wisconsin
Posts: 52
Default Re: removing exhaust manifold stud tricks ?

I was taught how to remove exhaust studs many years ago when I went to tech school. Heat the manifold with a torch around the stud (not the stud) until it is red hot. Take a water soaked shop rag and quech it quickly. Then grab it with a visegrips and use a back and forth motion until it is out. I've done many dozens of manifolds through the years and it always works for me.
vpd66 is offline   Reply With Quote
Old 08-23-2011, 12:56 AM   #6
Red Green
Senior Member
 
Red Green's Avatar
 
Join Date: Dec 2007
Location: South Central Michigan
Posts: 1,900
Default Re: removing exhaust manifold stud tricks ?

Quote:
Originally Posted by vpd66 View Post
I was taught how to remove exhaust studs many years ago when I went to tech school. Heat the manifold with a torch around the stud (not the stud) until it is red hot. Take a water soaked shop rag and quech it quickly. Then grab it with a visegrips and use a back and forth motion until it is out. I've done many dozens of manifolds through the years and it always works for me.
I do it the same way without the water rag. If the stud starts to squeak when I am turning it out I stop and heat the manifold more.
__________________
"If the women don't find you handsome, they should at least find you handy."

"Unlike love respect can't be bought" H. Simpson
Red Green is offline   Reply With Quote
Old 08-23-2011, 01:27 AM   #7
omr
Banned
 
Join Date: Jun 2011
Posts: 723
Default Re: removing exhaust manifold stud tricks ?

had an old timer show me a little trick that has saved me from having to remove quite a few manifolds..

i heat the manifold carefully with a torch , obviously not to the point the cast iron starts to melt but to the point it is red , then i take a socket full of the same size nuts that would have fit on the stud and push it against the stud with my impact gun on reverse..

not sure of the science behind it but it has worked every time i have tried it , for some reason the cold nuts grab the stud and spin it out every time ..
omr is offline   Reply With Quote
Old 08-23-2011, 01:34 AM   #8
Agent1320
Senior Member
 
Agent1320's Avatar
 
Join Date: Aug 2011
Location: Texas
Posts: 394
Default Re: removing exhaust manifold stud tricks ?

If you can't get it out with heat, penetrating oil, wax, etc. Drop it off at a machine shop and tell them you want the studs removed and the threads chased and you want the flanges resurfaced. Won't cost much more than a simple resurface job and you'll have smooth/flat surfaces for a leak-free installation.
Agent1320 is offline   Reply With Quote
Old 08-23-2011, 08:12 AM   #9
NASTYZEN
Senior Member
 
NASTYZEN's Avatar
 
Join Date: Jun 2010
Location: St-Colomban,Que. Canada
Posts: 2,269
Default Re: removing exhaust manifold stud tricks ?

The principal about using heat to remove a stud is simple. If you heat metal it will grow. Therefore you heat the flange around the stud till it's straw colored. All the while trying to heat the stud as little as possible. The flange grows more than the stud,in theory..... I like the quench the stud idea,should shrink it as well and make the stud less plastic in consistency.
Anyhow,when I served my time in a muffler shop,when the above method failed we would torch the stud flush with the flange.Yep.
We had a cutting torch that was strait,not L shaped,for this purpose.
Cast iron melts at a higher temp than the steel stud, so we simply took a golden shower.
Heat the stud till it starts meting and squeeze the trigger and blow the stud out of the hole. The trick is to not stop t'ill it's all gone,or else it's impossible to start again. The open holes are a little trickier to do.
Once cooled ,Tap and your good to go.
We had heavy leather coats ,hats n gloves so as to not stop halfway thru a cut because of skin on fire.......
__________________
"Engineering is the art of modelling materials we do not wholly understand, into shapes we cannot precisely analyse so as to withstand forces we cannot properly assess, in such a way that the public has no reason to suspect the extent of our ignorance."
- Dr AR Dykes
NASTYZEN is offline   Reply With Quote
Old 08-23-2011, 08:30 AM   #10
rsanter
Senior Member
 
rsanter's Avatar
 
Join Date: Dec 2007
Location: visalia ca
Posts: 11,135
Default Re: removing exhaust manifold stud tricks ?

if you have the time then clean aff as much rust as you can and soak in penetrating oil to start.
then double nut the thing and heat the flange and give it a try.
if that dosent work then get the wax out and do it again

bob
__________________
my wife says that I have never met a tool I havent liked. people on the other hand......
rsanter is offline   Reply With Quote
Old 08-23-2011, 08:50 AM   #11
vpd66
Member
 
Join Date: Mar 2010
Location: Central Wisconsin
Posts: 52
Default Re: removing exhaust manifold stud tricks ?

Quote:
Originally Posted by vpd66 View Post
I was taught how to remove exhaust studs many years ago when I went to tech school. Heat the manifold with a torch around the stud (not the stud) until it is red hot. Take a water soaked shop rag and quech it quickly. Then grab it with a visegrips and use a back and forth motion until it is out. I've done many dozens of manifolds through the years and it always works for me.
I also use this method on every brake bleeder screw and have never had it fail. I've done thousands of brake bleeder screws over the years. In fact I did 2 just yesterday.
vpd66 is offline   Reply With Quote
Old 08-23-2011, 08:59 AM   #12
PCO6
Senior Member
 
PCO6's Avatar
 
Join Date: Dec 2008
Location: Newmarket, Ontario
Posts: 4,071
Default Re: removing exhaust manifold stud tricks ?

Like with rusted nuts and bolts, sometimes it's best to "tighten" the bolt (stud) slightly THEN start to loosen it. If you can tighten it 1/10 of turn or even 1/12 or so you can break the rust seal and that will allow penetrating oil to seep in better. I agree with the comments above though - heat up the manifold, and the studs as little as possible, and they should unwind.
__________________
PCO6 is online now   Reply With Quote
Old 08-23-2011, 09:09 AM   #13
diesel research
Senior Member
 
Join Date: Sep 2010
Location: gulf coast, TEXAS
Posts: 5,465
Default Re: removing exhaust manifold stud tricks ?

you are lucky for multiple reasons.
1. you have exposed threads on both sides
2. the part is removed and easily accessible
3. you aren't on an emergency deadline
4. (and most importantly) you stopped and asked for help BEFORE you broke something.


http://www.youtube.com/watch?v=cTRUX...ayer_embedded#!

http://www.youtube.com/watch?v=fjlnq...eature=related

http://www.youtube.com/watch?v=zZ1e8...eature=related

http://www.youtube.com/watch?v=wu460...eature=related
(while the bolt-out extractors won't help one bit, notice the use of heat and aero kroil along with vibration of impact or hammer)

So the common recipe includes heat (and or cold shrinking) various penetrants, and vibration/shock.

Since you have so much available time and space, I would LOVE to see what phosphoric acid or other rust removers do (ospho, jasco, naval jelly, or evaporust) Only a hypothesis, but I suspect it may help penetrants creep deeper.
__________________
Quote:
Originally Posted by Chuck122 View Post
Whenever I see someone using a claw hammer for mechanical work, I assume he is a retard.
diesel research is offline   Reply With Quote
Old 08-23-2011, 09:15 AM   #14
KCarGuy
Senior Member
 
KCarGuy's Avatar
 
Join Date: Feb 2009
Location: 50 miles outside Chicago, illinois
Posts: 1,876
Default Re: removing exhaust manifold stud tricks ?

I have had to do this several times.
I put the manifold in a vice, heat the stud with a torch then cool it with some WD-40.
This will shock the rust and pull in some oil.
Then heat the Manifold, while staying away from the stud...More WD-40.
Using a Double Jam Nutted or Vice Grip start working the stud Clockwise-Counter Clockwise until it breaks loose and it may complain the entire time.
It should then, come out.
Good Luck.
KCarGuy is offline   Reply With Quote
Old 08-23-2011, 09:46 AM   #15
zmotorsports
Senior Member
 
zmotorsports's Avatar
 
Join Date: Oct 2009
Location: Utah
Posts: 1,929
Default Re: removing exhaust manifold stud tricks ?

I have had good luck by spraying with Kroil and letting sit overnight. Then apply heat to the manifold boss and try to keep the direct heat off of the stud. Once heated wrap a wet rag around as much of the stud as possible to both cool the stud and hopefully shrink it somewhat and to make the stud more solid, less plastic, to endure the removal process.

Just before attempting to turn the stud outward smack the side of the manifold near the stud but not directly on the boss as you could deform it. This will sometimes jar the rust/corrosion just enough to break the surface tension and let the stud go.

For stud removal I use actual stud removal sockets that grip the stud on the shank but the double nut process will also work adequately.

Mike.
zmotorsports is offline   Reply With Quote
Old 08-23-2011, 09:59 AM   #16
ptschram
Senior Member
 
Join Date: Sep 2006
Location: In a Snap-On truck somewhere around Churubusco, IN
Posts: 2,029
Default Re: removing exhaust manifold stud tricks ?

I have to remove tie rods that are FROZEN into the tie rods, along with exhaust studs.

I set them up so that my salamander is blowing directly on them. Get them close enough that they're too hot to hold, but not so they change color. On the second day, expose them to heat for an hour, pull them away, squirt with Kroil, repeat heat, repeat Kroil, repeat until you're tired of doing it.

After the second or third day, apply a pipe wrench to the stud, gently try to tighten it, Kroil, loosen with pipe wrench, The vast majority spin right out.
ptschram is offline   Reply With Quote
Old 08-23-2011, 10:10 AM   #17
tatra
Senior Member
 
tatra's Avatar
 
Join Date: Dec 2007
Location: pirate contest city
Posts: 4,232
Default Re: removing exhaust manifold stud tricks ?

i have had good lock welding the next size up nut on broken studs, letting it cool and then turning it out...........the heat from the weld seems to break the rust ...........used this numerous times on brken bolts and studs where the t stat housing fastens to the block..............all of the above do infer one common item, patience...........
tatra is online now   Reply With Quote
Old 08-23-2011, 10:10 AM   #18
jayoldschool
Senior Member
 
Join Date: Apr 2006
Location: Canada
Posts: 1,264
Default Re: removing exhaust manifold stud tricks ?

Heat and wax. Good video on youtube...
jayoldschool is offline   Reply With Quote
Old 08-23-2011, 12:25 PM   #19
Test Tech
Senior Member
 
Join Date: Oct 2010
Location: Automation Alley
Posts: 235
Default Re: removing exhaust manifold stud tricks ?

Quote:
Originally Posted by KCarGuy View Post
I have had to do this several times.
I put the manifold in a vice, heat the stud with a torch then cool it with some WD-40.
This will shock the rust and pull in some oil.
Then heat the Manifold, while staying away from the stud...More WD-40.
Using a Double Jam Nutted or Vice Grip start working the stud Clockwise-Counter Clockwise until it breaks loose and it may complain the entire time.
It should then, come out.
Good Luck.
I agree with this with two exceptions:
1: Use a better oil than WD, use either kroil or blaster.
2: You may need to perform several cycles of heat/oil spray in order to succeed. If you do this once and it doesn't work, repeat until it does.
Test Tech is offline   Reply With Quote
Old 08-23-2011, 01:00 PM   #20
srmofo
Senior Member
 
Join Date: Oct 2009
Location: SW ohio
Posts: 5,504
Default Re: removing exhaust manifold stud tricks ?

I always apply heat before attempting to break anything like that manifold stud loose. Usually heat red and quench once, then reheat till its hot, but not glowing. Apply wax and break it loose, work it back and forth while applying more wax until its turning easily. if it starts squeaking apply more wax.

most importantly, dont force it
srmofo is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 07:40 AM.