Broken Exhaust Stud

[Redf150]

hock: Anybody have any kind of luck removing a broken stud at the exhaust manifold outlet, where the exhaust bolts up? On a 86 Aspencade, or 1200 0r 1100.
:oops:

[Oldman]

Wow, that sucks. Maybe lots of wd-40 and a good set of vise grips?

[Redf150]

Thanks for the info.
I will let you know how I make out

[bs175dths]

If there is anything to grab onto, try Bob's suggestion but get yourself the smallest vise grip pliers you can find. I have a 3" long pair of grips which means it has a small mouth, but still grips like vise grips, grip. (get that?) If the stud will rotate, rotate it as far as you feel comfortable without slipping the hold on the stud, then rotate it back to start. Back and forth will take some time and patience but will eventually walk the stud out of the head. I once removed a broken stud from a '84 Mustang water pump with less than 1/8" exposed. Darn thing was about 1.5" long and took the better part of three hours to remove and days for my back to recover, BUT that sucker came out!

If there is nothing to grip, the small ez-out may be the next step.

Good luck and go slow. Walk away for a few minutes if you have to........

[unionjack]

Make sure to use a genuine 'Vise-Grip' not a cheaper made in Chine model, those do not grip like they should and will round off what you have left sticking out.

If you are drilling be sure to try a punch and then a small drill bit first to get started in the center of the stud and not slip out into the softer aluminum around the stud.

[Redf150]

Thanks all. I appreciate. Will let know the outcome

[85GL1200I]

Agreed on the genuine Vice grip. You want pliers with qualtity, hardened steel that will dig into the stud, not round it off. And Bob is right, heat works wonders. Good luck...................

[Guest]

I have great success using PB Blaster Penetrating oil and lots of heat from a torch.

[wingandaprayer]

Save the money on the PB as a 50/50 mixture of acetone and ATF actually works better...wish I could find that study.

DO NOT HEAT THE AREA AROUND THE STuD....avoid it anyway and just HEAT THE STUD.
Timing is important...as the stud cools,the heat will radiate to the head (hot goes to cold) and this will cause the head to expand as the stud contracts. What happens here is the stud expands and breaks the magical bond it has made with the surrounding metal. I often get in arguments (Me????) with guys about whether to heat the stud or the casting. If you heat the casting it expands...true...but what happens to the hole in the center of an inner tube when you blow it up??? It gets smaller.....gripping the bolt.....while the bolt expands as the heat moves into it.......(sigh).

My instructor in a handyman's welding course showed us how to remove the ugliest seized & busted studs broken off in stuff you could drag in there by doing what Bob said. Broken stud in cast iron? "If you can get in there weld a nut to the stud and go have coffee - come back and turn it out with a wrench." He explained that in addition to what Bob said about the surrounding metal warming as the fastener cools, steel expands and contracts in all directions when heated - so the fastener shrinks in diameter as it cools as well as the surround metal expanding...

Be carefull heating aluminum...

[Redf150]

:YMAPPLAUSE: Thanks all for the information.
Will let know how I make out. \:d/

[Redf150]

:twisted: Well now I've done it.
Now I have 2 broken off extractors where I had broken studs in the exhaust.
The head is off and now looking for a machine shop to EDM these out.
Unless someone has a right side head for sale.
Thanks for any information.
In a world of trouble right now, but still see light at the end of the tunnel.
Glenn
:twisted:

[85GL1200I]

You did call that one Bob. :YMAPPLAUSE:

Glenn, it should be no big deal for a competent shop to remove those studs.

You are going to need a head gasket and associated o rings, maybe you want to get that stuff ordered while you are waiting for the head to get straightened out.

[Redf150]

:oops: Bob
I am red in the face. Was listening too you, but had some confidence in my actions.
But did not pay off.
Will be looking for a competent shop too do the repairs and will be ordering gaskets and o,rings and such.
Not giving up on this project yet.
Thanks for all the helpful suggestions.
Will keep informed.
\:d/

[joe turner]

Save the money on the PB as a 50/50 mixture of acetone and ATF actually works better...wish I could find that study.

DO NOT HEAT THE AREA AROUND THE STuD....avoid it anyway and just HEAT THE STUD.
Timing is important...as the stud cools,the heat will radiate to the head (hot goes to cold) and this will cause the head to expand as the stud contracts. What happens here is the stud expands and breaks the magical bond it has made with the surrounding metal. I often get in arguments (Me????) with guys about whether to heat the stud or the casting. If you heat the casting it expands...true...but what happens to the hole in the center of an inner tube when you blow it up??? It gets smaller.....gripping the bolt.....while the bolt expands as the heat moves into it.......(sigh).

My instructor in a handyman's welding course showed us how to remove the ugliest seized & busted studs broken off in stuff you could drag in there by doing what Bob said. Broken stud in cast iron? "If you can get in there weld a nut to the stud and go have coffee - come back and turn it out with a wrench." He explained that in addition to what Bob said about the surrounding metal warming as the fastener cools, steel expands and contracts in all directions when heated - so the fastener shrinks in diameter as it cools as well as the surround metal expanding...
W&P advice works on studs with broken easy-outs in them ,
Be carefull heating aluminum...

[Redf150]

Got it all back together.
Fired it up.
It does run, but i am not too keen on cylinder's 3 and 4.
Good compression and getting fire at the plugs, but not as much fire as on 1 and 2.
1 and 2 have a very good spark gap at the plug good fire and snap.
Traced the plug wires back to there respective coils. I'm guessing a coil that is not in the best of shape?
3 and 4 do not have as much snap as 1 and 2.
I moved the plugs around and it does not follow the plugs. I ohmed the plug wires they seem ok.
I ohmed at the plug ends as well and they are also in spec.It starts right up and will idle down too 1100 and I can throtte it up, but there seems to be a lag in throttle response. Not really sure about that 3 and 4 spark power.
Any suggestions?
Thanks :roll: