broken exhaust stud removal

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jazak5

jazak5

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is there enough material at the (lucky front) exhaust stud (water jacket) 340 to do a helicoil ????
all means to remove the broken stud has failed//heat/crc freeze/koil/pb blaster/brake fluid/ drilled a 1/8 hole thru stud to see if the penetrating oil would work with no results with extractor
 
Depending on how much patience you have and if you drilled the hole in the middle of the stud....you can keep drilling larger and larger until all that will be left are the threads of the stud. Once you get close to the threads you can get a very small center punch and start breaking the threads out of the hole by pushing them to the inside. A pick/scribe also helps to get the pieces out of the hole. I'm a machinist and I have done this many times with broken studs/bolts/screws. It takes patience and care.

Treblig
 
mopowers said:
Try tapping with the proper size tap first. May not have to helicoil.
Click to expand...
If the stud is broken close to the face of the head you may be able to use a cutoff wheel and make a grove in the stud. This will allow you to use a straight screw driver and grab what is left of the stud minus what you have already drilled from the center. This solution works best before you do any drilling but you may get lucky depending on how much of the stud you drilled. I have been there before. Whatever you do don't breakoff the easy out or tap then you will be screwed. Good luck!
 
Oh I just remembered a trick that worked for me once. If you have access to a mig welder you can build up the stud with weld and grab it with a pair of vise grips then spin it out.
 
I use the manifold as a guide to get a good center. I forget what size the hole in that casting is.that's the size drill that creates my center though. Then I drill up to the 1/4 inch and clean up with the 5/16 tap. No helicoil req'd. Helicoil is doable but I would still use the manifold as a guide for that larger drill.
 
RedFish said:
I use the manifold as a guide to get a good center. I forget what size the hole in that casting is.that's the size drill that creates my center though. Then I drill up to the 1/4 inch and clean up with the 5/16 tap. No helicoil req'd. Helicoil is doable but I would still use the manifold as a guide for that larger drill.
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That's an awesome idea!
 
I have gotten two frozen and broken studs out recently and saved the original threads.
Probably done 30 of them over my lifetime, and I always do it the same way.
Using a mototool to concave the end of the stud to get a good center and just worked up in sizes until I was at the size of the hole minus the threads.
Then just slowly worked the tap in and back out a few times knocked the left over threads out.
Probably spent 30 min or less on each one, but like mentioned patience is critical (especially on your first pilot hole drill)
The closer you are to centered on that first drill will dictate how the rest of it goes, and that is why I concave dress the end of the stud with the mototool first.
 
not sure if it's ok to do on a head but a great way to get a broken stud out is to heat it with s torch and touch beeswax to it. The heat will instantly suck the beeswax into the threads and the stud will come right out
 
twistthethro said:
not sure if it's ok to do on a head but a great way to get a broken stud out is to heat it with s torch and touch beeswax to it. The heat will instantly suck the beeswax into the threads and the stud will come right out
Click to expand...
I'm sure if you use a propane torch it wouldn't overheat the head. Heads get up to 350/400 degrees normally (in certain areas). I have heard that beezwax does work well for removing stubborn bolts, lots of u-tube videos!! But if the OP has the stud broken off "flush" he'll have to use an easy out once the wax gets in there.



Treblig
 
As trailbeast said, I use a carbide ball burr on a grinder to get a good center on uneven ends, sometimes I use a small wafer wheel to grind the edge flush, then put the divot in it.
I'm kind of the "specialist" wherever I work at this sort of thing, I flag .5hr/hole.....period. One trick that will work, You will need to make sure the head is reasonably clear of all
coolant & other flammables, is to drill up 'till the bolt/stud is 'thin".......then get a REAL torch w/a cutting tip and fire the hollowed broken fastener up 'till it's about to melt out.
Let it cool 'till it loses color, then quench it by spraying it with water. The thing will shrink up and loosen in there, may take a couple runs, but it will happen. You won't hurt the
head at all if you work fast & focus the heat on the fastener only, just used that one on the 352FE engine(late 50's Furd) in My tow truck, manny stud in blind hole.
Rust is hard, but it is also brittle, the heat can crush it & breakdown it's structure.
Oh.........and left hand drill bits w/a reversible drill................
 
I'm curious what heat you used?

I recently had an experience with this. Putting headers on, buddy snapped the back stud inside the head. Ok drill it out and gets an extractor. Snapped the extractor inside the head. Well ****. Get out the drill again, go buy a fancy carbide bit. Drill out the extractor. Use a different extractor. Rounded it off first go.

Ended up having to go the exhaust shop since we didn't have access to heat to get it out. Took the shop 6 hours with their oxy torch to burn it out and get it re-studded and going. Pain in the *** right there.
 
Std. oxy/acetylene cutting torch, w/a smallish focused flame, keep pulling back if the edge starts to look like it's about to melt, maybe 10-15seconds or so it should be glowing
bright orange. In the case of my ancient Ford manifold, it took a while longer in totality, not a job for the impatient for sure. The other stud I had to weld a nut to the end, and
go thru the heat process numerous times before it broke loose, I also had to fire the broken stud w/a torch before welding the nut on to get a satisfactory weld. Sucked in the
truck, but if you think I was going to start taking all 8 of the 60yr-old manny to head bolts out.................:rofl::rofl:
 
Killer6 said:
Std. oxy/acetylene cutting torch, w/a smallish focused flame, keep pulling back if the edge starts to look like it's about to melt, maybe 10-15seconds or so it should be glowing
bright orange. In the case of my ancient Ford manifold, it took a while longer in totality, not a job for the impatient for sure. The other stud I had to weld a nut to the end, and
go thru the heat process numerous times before it broke loose, I also had to fire the broken stud w/a torch before welding the nut on to get a satisfactory weld. Sucked in the
truck, but if you think I was going to start taking all 8 of the 60yr-old manny to head bolts out.................:rofl::rofl:
Click to expand...
DOESN`T SOUND LIKE THE ENGINES WERE IN VEHICLES. I `VE GOT A NEPHEW THAT HAS ONE IN A 4.7 DAKOTA THAT IS BROKE OFF IN #7, UNDER THE POWER BRAKE RES., WAS THINKING ABOUT PULLING THE LEFT FRONT WHEEL AND INNER FENDER PANEL OUT TO TRY TO GET TO IT, ANY THOTS ? excuse the caps!
 
To start with "Never Panic" like others have said the start is everything!

Drill centered and straight and keep going to a larger bit till you are just short of threads and fully through the old stud. Then use the extractor if needed. Most often by the time you get to max drill bit size it works itself loose and you can spin it out by hand.

The last one I did I got over confident and broke the extractor. Used a center punch at that point to drive the extractor through into the water jacket. Went one more size larger on the drill bit and the rest spun out. Patience is everything!
 
If the stud is broken close to, or even out of the hole, simply weld a nut onto the stud and back the stud right out.
 
famous bob said:
DOESN`T SOUND LIKE THE ENGINES WERE IN VEHICLES. I `VE GOT A NEPHEW THAT HAS ONE IN A 4.7 DAKOTA THAT IS BROKE OFF IN #7, UNDER THE POWER BRAKE RES., WAS THINKING ABOUT PULLING THE LEFT FRONT WHEEL AND INNER FENDER PANEL OUT TO TRY TO GET TO IT, ANY THOTS ? excuse the caps!
Click to expand...
Pretty much covered it all in posts #12 & 15, and the above examples WERE in the vehicle, accessibility is usually the biggest hurdle. I have reversible 90deg. drills,lefthand bits,
and other things to help overcome some of those challenges, but disassembly and jacking/tilting engines is a must sometimes(I bill accordingly). If it is bad enough, it can be
better to pull the part off,time/wise & success/wise. 1969383S reinforced it, start slow & get the best access to the offending unit, the first drill thru is the most important one.
Get quality bits that cut& hold an edge, the last 3rd gen HEMI I had to do mannys on took a toll on my good bits, God help you if you're using junk! If you've got more than a
couple to fix, best get a bit sharpener or know how to use the bench grinder w/a fine wheel to keep 'em sharp.
In the case of using heat, I make & place heat shields to protect things if needed, some things just have to come off or get moved. Trial run putting the torch & yourself in
position and practice "pulling out" quickly once or twice and have a spray bottle w/H2O ready, just in case............trust me............
Once I'm ready to drill, it's sometimes helpful to screw a stud/long bolt into another hole near Your line of sight, use it to keep the bit squared up in that plane.
 
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