Getting out a broken bolt

[brother chris]

I broke off a bolt on my o/b and after drilling a pilot hole in the bolt, we used and awl to try to extract it. The bolt that broke is used for the water jacket.
The awl broke off and is stuck inside with the broken bolt.
We have gone through, over 15 drill bits so far, with no luck.
I guess the awl is made from the same material as the drill bits are made of.
So, does anyone have and ideas what I should use to drill the broken awl and the bolt out with?
I'd rather not take it into a machine shop without trying to drill it out first.
Thanks for any help.
B.C.

 

[bjcsc]

Re: Getting out a broken bolt

Common scenario. Easy-out type devices usually cause more trouble than they're worth. You might be able to drill it out, but you need at least a cobalt bit. If you can heat it red hot you will take some of the temper out and make it easier to drill. Can you get to the other side of what's left? Can you post a pic?


---
I looked in my cabinet for a plate and there it was...a bowl

 

[Paul Moir]

Re: Getting out a broken bolt

I doubt you'll be able to get it red hot when it's encased in aluminium like that.
If cobalt won't get it, you may have to use a carbide drill. But I'll warn you they're very expensive as far as bits go. Might be worth trying to hit it with a cheap carbide tipped masonry drill bit though. It might be enough just to hack up the awl tip.
I'm guessing you're dealing with chrome-vanadium tool steel, which is likely hardened to 60+Rc. Unfortunately cobalt bits are right around there.

Finally, if you've got a dremel and a steady hand, you may be able to massacre the tip or the metal around it using the carbide burrs Princess Auto sells in the surplus section. They're less than $10 I think. They come in a clear plastic case with colourful bands. The smaller ones are useless since they break too easily when used in a hand tool, so get whatever one has the biggest burrs in it.
Those bits from PA are a real life saver. I use them to "punch" the centre of broken bolts when I'm drilling them, or to correct off-centre holes when drilling. I guess that's all the fun & excitement when dealing with old salt-water outboards!
EDIT: They're also the tool to use when blasting out old tile grout!
The ultimate answer is an EDM drill, but that's a trip to the machine shop.

 

[Bondo]

Re: Getting out a broken bolt

Did you drill Clean Thru the broken bolt, before you broke the Awl,..??....

Do you have access to a Stick Welder,..??....

By using Rubber Tubing as a Shield,.... You can usually burn a rod onto the broken piece,..... Then release the stinger,+ weld the Rod to the Bolt..... And while doing that, you've put abunch of Heat into it Quickly......Quench it to break the threads Free,.. a shot of good penetrating oil,..........
And,....Hopefully,.. It'll turn right Out.....

 

[tomatolord]

Re: Getting out a broken bolt

easy outs - they are made specifically for this - you can get them at an auto parts store.

They are reverse threaded drill types - you screw them in counterclockwise so as you are tightening them into the material you are also screwing out the bolt.

soak the bolt in pb or other penetrating oil and then try it with the easy out.

 

[brother chris]

Re: Getting out a broken bolt

Hi guys,
I will try to find my camera to take a pic.
No, we never got to the other side of the bolt when we were drilling originally. It looked like we had enough drilled out, so that is why we used the awl, but then the awl broke off.
I do have a stick welder....but the broken bolt is recessed in, about 1/4" from driling it so much, so I can't put the broken bolt back on it and weld it. Good idea though.
I did have a little luck with a rounded dremel bit that I had, but I dulled that. And boy are they expensive! I think that if I used just those bits, then it would probably cost me over $100.

 

[brother chris]

Re: Getting out a broken bolt

Tomatolord. I have 2 different easy-outs and I can't get in there to use them.

 

[Aquaman]

Re: Getting out a broken bolt

I just went through this...what a PITA! What size (diameter) is the broken bolt? I used small bits in a dremel to drill around the broken ez-out then broke/shattered the ez-out with a cold chisel I shaped on my grinder. After all this I was still left with the original broken bolt still stuck. I drilled the hole 1 size bigger going as far down and into old bolt as I could and then threaded the hole and loctited a stud into place.

Good luck.

 

[brother chris]

Re: Getting out a broken bolt

Thanks Aquaman,
I am going to try checking Princess Auto for some cheap dremel bits, because I have a feeling I am going to need a few of them!

 

[Bondo]

Re: Getting out a broken bolt

Weld the End of the Welding Rod to the Broken Parts,........
Not the Broken Bolt back together........

Like the 1 in this pic......

Btw,....... If you Drill Completely Thru the Broken bolt,... It Relieves some of the Stress on it,+ makes Removal Possible........
Just drilling deep enough to insert the removal tool is Never a Good Idea...........

 

[rwise]

Re: Getting out a broken bolt

I like to use left handed drill bits, half the time the broken bolt will come out with no problems before the hole is finished, but its a bit late for that now, good luck.

 

[KRS]

Re: Getting out a broken bolt

Bondo,

Where would you place your work clamp in that scenario?

 

[brother chris]

Re: Getting out a broken bolt

hey bondo, I thought that is what you meant, but won't the welding rod break when I try to turn the bolt out? The welding rod itself is not stronger than the awl and broken bolt.
How do you remove the broken bolt once you have welded the rod to it? That is the part that is confusing me
Thanks, B.C.

 

[Bondo]

Re: Getting out a broken bolt

Chris,......Normally,... The Heat you put into the bolt when Welding to the End of it,+ The Cold Water Quench will Break the threads from the Hole,.....
That and Alot of Penetrating Oil, with some Tapping with a Hammer,...
Will Usually allow the broken piece to be Turned out with the Rod,+ a small pair of Vise-Grips.....
The Tubing on the Rod needs to be Held down against the hole to keep the Heat,+ Splatter in control....

'Course,.... Sometimes it takes More than 1 Try......

KRS,....... Anywhere you can get continuity on the Base metal....... I used the shoe on the bottom of the Flywheel Cover on that 3.0l,.... You can See the scratches in the picture.....

 

[brother chris]

Re: Getting out a broken bolt

Thanks bondo, I will give it a shot.
Much appreciated,
B.C.

 

[Paul Moir]

Re: Getting out a broken bolt

Dropped by PA last night. They have two sets there, one with a bunch of bits for $25 which is kind of useless, and a much smaller set of useful bits for $7. You want the $7. They are solid carbide unlike the dremel brand bits which are HSS, so they won't wear out like them.

I've never had much luck welding smaller screws and bolts like you normally find in an outboard. But my welding skills are nowhere near Bondo's and the only thing I've tried it with is wirefed rather than stick. Perhaps that's the problem - the weld pool built up too quickly on top of the very well cooled, being encased in aluminium screw.

 

[speedwrench]

Re: Getting out a broken bolt

Wire feed has better control than stick for this. If it's 1/4" down, fill with weld to the surface, then lay a nut on top of weld and weld the center of the nut to that. Or lay a washer on the weld, weld it to the broken bolt, then weld a nut on top of that. Large fender washer will help keep buckshot off area around bolt. Quench and pentrating oil, it will spin right out. Chase threads and blow out hole. May have to Heli-coil threads. Did 70's salt water Mercury for friend few weeks ago, had dozen or so 5/16" and 1/4" twisted off, all came out without damage to threads.


Dave

 

[bassboy1]

Re: Getting out a broken bolt

Another suggestion. Try one more time at drilling a hole through it. Then run a self tapping hex head screw coated with loctite down the whole.Wait for the loctite to dry then use a socket to run the bolt out. just make sure the hole is the size of the SHANK of the screw. let it tap its own threads. And go heavy on the loctite.

 

[PW2]

Re: Getting out a broken bolt

Years back in Port Angeles, Wa there used to a machine shop that had some sort of drill that was an electrode with a hollow tube--he would center the piece with the broken bolt in the thing, put the appropriate size bit in it, and it would run automatically and stop when it reached the bottom of the threads. You'd be left with the core of the bolt inside the bit, some metal shavings where the threads used to be, and the rest of it as good as new.

It'd take about 2 minutes and he'd charge about 20 bucks or so, but it was absolutely invaluable if you wanted to work on outboards primarily used in a salt water environment.

I had it done several times and it eliminated all the headache--well worth the $20