Sheered a bolt because i'm manly

Well, was replacing the front mount yesterday, it's got 4 bolts.

Loosened two just fine, sheered the next, and the last one felt like it was going to sheer as well, so i chickened out and just tightened the other two and left it.

Mount NEEDS to be replaced, it's cracked pretty badly.

Soooo....

What do?

I'm not real psyched about trying to drill it out, because 1) it's not really something i trust myself to do, and 2) i'd have to remove the bumper, radiator, and intercooler to get myself enough space to get a drill there i think.

Any ideas that DON'T require me dismantling the entire front of my car? Again.

2 words for you: Easy-Out

Sell it and buy a miata?

Easy outs only work in theory. In practice I have NEVER actually seen one work, actually, I have only ever seen them break off little bits of very hard material into your now useless stub of a bolt.

/Off topic alert

Why is it called "shearing" the bolt? The bolt is not in shear when you over-torque it. To shear a bolt what you would need to do is press really hard on it from the side. Plus, you probably didn't mean to say "sheer".

http://en.wikipedia.org/wiki/Shear_stress

/Back on topic

Take a picture for us. Welding may be the answer.

tuna55 wrote: Easy outs only work in theory. In practice I have NEVER actually seen one work, actually, I have only ever seen them break off little bits of very hard material into your now useless stub of a bolt. /Off topic alert Why is it called "shearing" the bolt? The bolt is not in shear when you over-torque it. To shear a bolt what you would need to do is press really hard on it from the side. Plus, you probably didn't mean to say "sheer". http://en.wikipedia.org/wiki/Shear_stress /Back on topic Take a picture for us. Welding may be the answer.

My buddies and I have had good luck with them, and you are right, luck and patience are requirements 1 and 2 to even have a chance in hell of them not disintegrating. Alternatively you could get a place that does electric discharge machining to have it out, thoughI don't know how they'll feel about it if the car still has fuel lines and a gas tank in the body...

I've used easy outs extensively and they're fine, you do have to drill a hole though.

Pictures help.

I'll try to take a picture...

Welding, you mean weld something to what's left of the bolt for removal? I'm pretty sure i took too much of the bolt off to get anything down there. And welding the mount to the transmission would be a trick. Steel mount, and i'm fairly sure the trans case is aluminum.

Bob... if i could get a decent Miata in place of this thing, i would in a heartbeat, but i don't want to settle for a crappy Miata.

I'm hoping an easy out works... It's not exactly a small bolt, though, (17mm) and if it's stuck good enough that i couldn't get it out conventionally, then....

tuna55 wrote: Easy outs only work in theory. In practice I have NEVER actually seen one work, actually, I have only ever seen them break off little bits of very hard material into your now useless stub of a bolt.

Agreed. I've only ever had them break off and then provide an even harder metal to deal with.

Weld a nut to the top of the bolt, if necessary just fill the 'hole' in the nut with weld. Chances are that the heat into the bolt will loosen it sufficiently.

I've recently had good luck with screw extractors. The key is to get the largest hole possible in the dead center of the broken piece. Often easier said than done, but once you've got that hole drilled, it's cake.

tuna55 wrote: Easy outs only work in theory. In practice I have NEVER actually seen one work, actually...

The man that named the "easy out" had a poor command of the English language; there's nothing easy about them. The fact that most of them are tapered means that when tapping them home, they will tend to spread the top of the broken bolt, tightening it even further in it's hole.

In my experience, bolts that break when overtourqued going in, come out most of the time, as the threads are still clean, but bolts that twist off when coming out are frozen in there good, and are gonna put up a fight.

Copius amounts of penetrating fluid and heat help a lot; removal shouldn't be attempted without using one or the other, or both.

Personaly, I've had pretty good luck in tight spaces using a reversible angle drill and a left handed drill bit about half the diameter of the bolt. Since I can't get as much pressure on the angle drill as a straight-on drill, I often use an appropriate length board or pipe to get more leverage. Start off with a small regular bit for a centered pilot hole, then move up to the LH bit. Often it will snag and unscrew the bolt really quick. Same concept as an extractor, but self drilling, and not tapered.

BoxheadTim wrote: Weld a nut to the top of the bolt, if necessary just fill the 'hole' in the nut with weld. Chances are that the heat into the bolt will loosen it sufficiently.

This.

Hrmmm....

New question, because apparently in addition to being manly, i'm also borderline retarded:

Turns out that i was trying to take the wrong thing out. The BRACKET attaches to the trans, and the MOUNT attaches to the crossmember. I had it backwards.

So i no longer need to take that piece off.

Completely stupid OMGYOUREGONNEDIE idea to just leave it alone and drive as is, with the reasoning that there's still 3 of the 4 bolts there and solid? One of them is just a spare, right?

(Yes, i'd get it fixed. Eventually.)

For what it's worth, i beat the living dog E36 M3 out of the car yesterday, and my transmission didn't fall out of my car or anything.

914Driver wrote: I've used easy outs extensively and they're fine, you do have to drill a hole though.

THIS^^^

I use them a lot - some specialty parts on old bicycles are harder to find than unicorn farts - easy outs can help save cutting an old off sized stem or keep a frame intact.

tuna55 wrote: Why is it called "shearing" the bolt? The bolt is not in shear when you over-torque it. To shear a bolt what you would need to do is press really hard on it from the side. ... http://en.wikipedia.org/wiki/Shear_stress

BUT ... Torsion creates shear stress perpendicular to the radius. Torsion Wiki

slantvaliant wrote:

tuna55 wrote: Why is it called "shearing" the bolt? The bolt is not in shear when you over-torque it. To shear a bolt what you would need to do is press really hard on it from the side. ... http://en.wikipedia.org/wiki/Shear_stress

BUT ... Torsion creates shear stress perpendicular to the radius. Torsion Wiki

Well I'm glad we cleared that up.

In reply to tuna55: It is called shearing a bolt because it is shear, only not the kind you are thinking of. It's more like this: http://en.wikipedia.org/wiki/Torsion_(mechanics)

+1 vote for welding, preferably with a MIG, although at 17mm you MAY be able to coax it with an arc welder.

Edited to say I got beat to the point...

I used a "rigid" brand (think Home Depot) screw extractor kit a time or two that I liked better than an EZ Out.

You drill a hole and then insert a fluted/serrated pin. Then you slip a nut-shaped collar over the fluted pin and use THAT to turn out the old bolt.

You sill want to use LOTS of PB Blaster and heat prior to trying it (as I'm sure you can break one of those also).

For what it's worth...I remember researching (and not buying) one of these kits long ago and I think it was the same as a Blue Point and/or SnapOn screw extractor kit...I think.

Clem

There's no "borderline" about it friend!

Bobzilla wrote: There's no "borderline" about it friend!

Look here, ginger....

NYG95GA wrote: Personaly, I've had pretty good luck in tight spaces using a reversible angle drill and a left handed drill bit about half the diameter of the bolt. Since I can't get as much pressure on the angle drill as a straight-on drill, I often use an appropriate length board or pipe to get more leverage. Start off with a small regular bit for a centered pilot hole, then move up to the LH bit. Often it will snag and unscrew the bolt really quick. Same concept as an extractor, but self drilling, and not tapered.

I have had good luck with reverse cut drill bits (probably a 50-50 chance of this working on it's own). Where this doesn't work, I get about 50-50 success rate out of easy-outs. Granted this covers 75% total of sheared bolts, but that last 25% where I broke a chunk of tool-steel into a bolt sure isn't any fun.

i vote 3 bolts is just as good as 4 not seeing a picture of said bracket.

I broke just about every nut and bolt on the front end of my formerly rust 1990 Miata. Its amazing how weak those rusted bolts were as some just broke off with one turn of the wrench.

I replaced all of the front end components - control arms, hubs, calipers, lines etc etc.

I also sanded and repainted the wheel wells with Por 15.

Plus one for reverse drill. That alone will back out the bolt most of the time. If not, you have a convenient hole to break an ez-out in. :)

Ohh god Mohr's Circle..

I'm really glad I got an engineering degree so I understand it....

but..

I'm really glad I got an MBA so I never have to deal with it again...............