Help broken bolt in crank!!

I just broke off the bolt that holds on the harmonic balancer on a 305 chevy any tips on getting it out??

 

did you break it taking it off or putting it on?, is it flush? was it stuck?

 

is it cross threaded?

 

did ya break it putting it in or taking it out.

how deep>?

well hit it hard with penetrating fluid and try to catch a corner with a flat head screwdriver to turn it out lightly tapping with a hammer, you could try left hand bits and extractors but they rarely work, im sure someone will have a better idea than me,

if its right at the surface or some sticking out you can weld a nut to it but becareful

 

do you have a mig welder? build up some weld on the broken stud, making sure not to weld it to the crank, once you have enough material built up weld an old lug nut to that & use that to unbolt it. works like a charm

 

No matter how or why it broke unless its sticking way out your option is probably going to be to drill it and either an easy out or a little finess 'n' tap work.

Never the less its probably not going to be easy. But that's hot rodding.

If you were closer I'd volunteer to come by and help you screw it up worse.

 

I broke it putting it in thats what i get for using old hardware its about flush not too far down

 

if its flush and the threads are not screwed up just try putting your thumb against it and try turning it out, i have done this 3 times now over the years, its just a chance but it has worked for me, if i do have to weld i use a piece of 16ga about an inch wide and 4" long with a hole a little smaller then the bolt drilled in one end, i used to use nuts to weld on the end but they can cause the bolt to arch onto the threads, i clamp my ground onto the 16ga. also i have cut a slot into the bolt with a zip disk and used a impact drived as well.

 

This is probably a pretty good size bolt....I would imagine. The weld trick is probably the best...if you have a welder handy. I've drilled them out before with a smaller bit than the hole so that you don't mess up the thread. Then used a tap to tap out the threads that are left. Just got to be real straight when you drill.

 

drill it with left hand drill bit and it might just back itself out. if not you can then use and ez out.

 

And when you get it out, don't install your balancer by using the "bolt". Borrow an installer.............

 

Was it threading in easy when it broke off? If so take a sharp punch and a hammer and try turning it back out.

 

I got a broken bolt out this weekend.. It broke off putting it in. I took a sharp punch and tapped it out at an angle. Not to sure how to describe the technique. but you catch whats left near the edge and tap it out counterclockwise. Once its out a couple of threads you can get it with your fingers or vice grips. Watch out with the thumb method.. sometimes it'll have a sharp burr.

 

Centerpunch the bolt before you drill it.

 

is it flush enough to cut a slot in it with a dremel tool or die grinder?

 

Grind it flush and pretend it's a 283.

 

Ditto, cept I use a 1/4" wide cold chisel and tap on half of it in the direction that would be tightening the bolt, just till it moves a bit free then reverse direction and "clock" it back out of the hole.
This has never failed me if the bolt was anywhere close to flush and wasn't already bottomed out in a blind hole.

And use an installer to pull the dampener on next time!

Installer = long enough rod with the correct threads the whole length and a screwdriver slot in the end, a couple of greased washers and a nut.
Screw the rod in the crank, almost but not all the way bottomed, then dampener washers and nut, tighten, untighten. Replace rod with correct bolt.

 

thanks guys yall rock

 

Wow sounds like you having fun!! I've never seen a bolt break off square. So if you have to drill it out it's going to be almost immpossible to drill in the center. Even if you try to center punch it. I take a round carbide bit for my die grinder. I have different sizes for different size holes. Place the bit in the hole against the broken bolt and grind a spot in the center of the twisted off bolt. Then center punch and drill away. I always drill all the way through the twisted off bolt to relieve the pressure on the bolt. Once I get a drill all the way through the bolt I go to the left hand bit and try to back the bolt out. If this fails I drill until a sliver of threads is all that's left then usaually it will spin out with a easy-out. Good luck>>>>.

 

had a broken crank bolt in a 55 Buick 322 pulled the radiator
grounded the center of the bolt flat
center punched it
drilled it
used an easy out
chased the treads with a tap
it worked

Pretty much what 5X said above, wasn't that fast posting it
bottom line this method works at least twice

 

305? pull the motor, weld a chain onto it and use it for a boat anchor. Probably save a bunch more problems and disappointments that haven't happened yet.

 

It's like this with me: I spent the last 40 years of my working career before retirement as a machinist, and still do a few for pay jobs along with building my roadster in my own machine shop.
My charges for accomplishing what you want, a broken off bolt removed, or the like, will be greatly affected on how badly you have ****ed up the job before you brought it to me. IOW, if you break off an "easy out" in a frozen bolt while trying to get it out, then bring it to me, the cost is gonna be in multiples of what it would have cost if you had brought it to me to begin with. Ever tried to drill out a hardened "easy out" remnant?
Dave

 

so how goes the battle?, did you have any luck getting the bolt out?