The best tools and methods for extracting broken bolts (5 Viewers)

[ScottyD]

ARGHHHHH!!!!!!!!!!!!

98 LC, little rust but it has beaten me once again. All three bolts for the transfer case shield and half of the bolts for the engine plate have broken off.

Stopped by Auto Zone, lifted truck, drilled out bolts, used OEM extractor set, broke 2 of the five trying to get the remnants out. Now I'll have to drill through hardened steel pieces of the extractors and start over. What's a quality set of extractors that won't break, and a better method to get those things out.

Also need to know what to put in there to keep the new ones from seizing to the old rusted nuts.

Photos, videos, etc...

ARGHHHHH!!!!!!!!!!!!

 

[95Fantasma80]

I've heard of torch, chisel, overnight pb blaster..

good luck

 

[Somebodyelse5]

you'll likely need to order from the interwebs to get the quality of tool you really need, unfortunately most stuff at local hardware or auto stores is pretty poor quality when it comes to bits, taps, and extractors.

There is a ton of info out there:
Penetrating oils


If you can weld:


Drilling through those extractors is going to be no joke, especially since the jagged shear face isn't going to provide a good way to start cutting... My vote would be to consider the welding method... if not, definitely go find yourself some carbide bits and get extra...

 

[SICARIO]

Broken extractors or drill bits: use a burr on a die grinder or dremel. Anything else will be laughed at by the hardened steel. I had one broken bit and nibbled it away with the dremel/burr method.

For the broken bolt, you’ll have to just drill and re tap if it’s rusted in there.

I had a few broken bolts when I removed my skids. Even with a broken stub sticking out with multiple applications of penetrating oil it wouldn’t budge. Drilling and tapping worked best. Start small, use cutting fluid, go slow.

If you remove too much material, go up in thread size. Alternatively you can use a rivenut.

 

[Somebodyelse5]

Broken extractors or drill bits: use a burr on a die grinder or dremel. Anything else will be laughed at by the hardened steel. I had one broken bit and nibbled it away with the dremel/burr method.

For the broken bolt, you’ll have to just drill and re tap if it’s rusted in there.

I had a few broken bolts when I removed my skids. Even with a broken stub sticking out with multiple applications of penetrating oil it wouldn’t budge. Drilling and tapping worked best. Start small, use cutting fluid, go slow.

If you remove too much material, go up in thread size. Alternatively you can use a rivenut.

yup^

Rivnut for sheet or frame tube. Insert like a threadsert or a helicoil for everything else.

 

[cruiserpilot]

If you have a bolt broken off, and you can manage it, put a nut over the broken bolt and then
tack weld center of nut to bolt. The instant heat loosens the rusty bolt and just turn it out
with a wrench.

 

[Bigsky80]

From my experience the quickest way is to just drill and tap. I've tried other methods and almost always end-up drilling in the end. Good luck.

 

[southdakotayota]

I agree with those above suggesting a rivnut. Drilling and tapping is not an option down there as the steel is too thin. I had to use them to repair several broken off bolts on the front skid and they are a dream to install. Ordered from fastenal .80 cents each in the same size to match all the original hardwear. Easy.

 

[BEG]

For removing broken bolts in the frame, I've always used alternating applications of heat (torch), shock (air hammer) and penetrating fluid and then increasing sizes of reverse drill bits. Usually, when enough of the bolt is drilled out, the reverse drill bit will just spin it out. Other times, I've drilled all the way through with about as large a bit as I can without putting the threads in danger and I have to resort to extractors, in which case, I use these rectangular profile types:

https://www.amazon.com/Blackhawk-Proto-DT-55-Extractor-5-Piece/dp/B004RH70AA

They grip very well and, although I've never broken one, the rectangular profile leaves some voids between the extractor and the bolt body where you can stick something in to pry them out.

 

[MuseChaser]

I had two of the three transfer case shield nuts break off on mine, too, as well as a left twist bit and screw extractor while trying to get one of them out.... after a good long soak wt PBBlaster. Did NOT have cutting oil on hand at the time, which probably would have saved the bit. Grinding with small Dremel bit, drilling to clean up, and then re- tappong worked well, but took a while and was no fun. New bolts w/ light coating of neverseize threaded in beautifully and gripped strong.

 

[cwmoser]

I have never had great success drilling with an extractor or even my left hand drill bits.

What works best for me is:
1-) Heat the bolt
2-) Apply penetrating oil
3-) Dremel out a grove and take a screwdriver and hammer and strike to turn bolt in loosening direction.

Allen head bolts are the worst to strip.

I also have some nut crackers but so far never used them.
Folks on the Mercedes forums say they are good if you have the room to tighten onto a bolt and use as vice grips or whatever tool to give you leverage.

 

[abuck99]

From my experience the quickest way is to just drill and tap. I've tried other methods and almost always end-up drilling in the end. Good luck.

Same for me- I’ve tried unsuccessfully on several occasions using extractors of various types. Quickest way Ive been able to remove broken bolts is drilling them snd then chased with a tap. Buy a couple of different sizes of COBALT drill bits and you’ll be good to go.

To avoid frozen hardware in the future use copper antisieze or blue locktite wherever possible.

 

[I Lean]

I'm in the "weld a nut over it" camp. Rarely does that fail for me.

 

[suprarx7nut]

Another vote here for drill and tap.

The extractors are more or less a running joke among all mechanics I know. They more commonly just make the job harder when the extractor inevitably breaks off and creates an even harder piece of steel to drill through later.

 

[ozbogan]

I drill them out with about 1/8 smaller of a bit v shaft. Maybe use a smaller bit for a pilot hole. Cutting/drilling compound will help a lot

 

[cwmoser]

I'm going to keep my eye out for some metal sleeves or tubing of various sizes.
A poster in another forum suggested to use a sleeve just big enough for the stud,
and then another sleeve inside the outer sleeve for your drill bit for more
accurate drilling out of studs.

 

[CanadianRockyCruiser]

If you have a bolt broken off, and you can manage it, put a nut over the broken bolt and then
tack weld center of nut to bolt. The instant heat loosens the rusty bolt and just turn it out
with a wrench.

I've used this method many times with great success