How to remove a Broken Bolt
#21
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My last EZ out attempt actually worked!! Joe, remember that AC bracket bolt that causes an oil weap when it's missing (or, in my case, broken)? I actually removed it easily with an EZ out. I was shocked. Must be living right.
I think the key with an EZ out is that it doesn't hurt to try but don't apply significant torque. It either starts backing out pretty effortlessly or you should be trying another method.
I think the key with an EZ out is that it doesn't hurt to try but don't apply significant torque. It either starts backing out pretty effortlessly or you should be trying another method.
Also how the hole is drilled can make or brake an ez out removal.
Heads off, and A LOT. I literally could have bought a running NA for what I paid, but it wasn't just the bolts. I managed to break off 4 of the 8 exhaust manifold bolts in each head while trying to R&R the broken iron manifolds. I broke 2 EZ-Outs before throwing my hands up and then ripping off the heads and the 9,000lb iron intake manifold and paying someone to fix it. I took the opportunity to have the heads completely rebuilt and also install some headers. Runs better and get more mileage now that all the valves seal ("more" is a relative term with a Ford FE.) Funny how that works...
I honestly didn't look, the total was hideous. I didn't WANT to know after 16 new valves, seats, seals, machine time and shop hours to get it all put together. The shop does GREAT work, but yee gods, they are expensive. I'd not hesitate to trust them with anything... if money was no object. Needless to say, I will think twice and explore many options before using them again.
I honestly didn't look, the total was hideous. I didn't WANT to know after 16 new valves, seats, seals, machine time and shop hours to get it all put together. The shop does GREAT work, but yee gods, they are expensive. I'd not hesitate to trust them with anything... if money was no object. Needless to say, I will think twice and explore many options before using them again.
I am going to guess about a grand for what you had done. I have done bunches of those heads, they are never cheap to fix right.
What casting number are they?
From the looks of that break, an EZ out should work.
Once the hole is drilled, about 1/3 the bolt dia.
Then taper the hole some at the top so the ez out will get a better bite.
Some penatraint oil once the hole is drilled all the way through the bolt will help
#22
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I've removed more than my fair share of broken bolts in my life (2A7X1). A few things that make easy outs easier to use and more likely to work:
Get a small ball burr![](https://www.miataturbo.net/attachments/engine-performance-56/63718-how-remove-broken-bolt-rotary_burr_ball_12mm_diameter.jpg?dateline=1357504047)
And round the top of the bolt. This makes it much easier to drill the bolt on center and reduces the chances of breaking a drill bit if the top of the bolt broke off in a jagged manner.
Use a tap handle instead of an adjustable wrench to turn the easy out.
![](https://www.miataturbo.net/attachments/engine-performance-56/63719-how-remove-broken-bolt-56c2c6fd0b826eee74c80dc59c55ba59812e1773_800x700.jpg?dateline=1357504047)
This allows for a more even pressure so the easy out is less likely to ****(
) over to one side and spin.
If the broken bolt is large enough that you can get a decent size easy out in it, while you are turning the easy out tap the end of it with the hammer. This helps seat it and makes it less likely to spin in the bolt. WARNING: this is generally the step at which I have broken most easy outs.
If the bolt really isn't coming out at this point, before you break an easy out in the hole, look to see how close to centered(and straight) you were when you drilled the bolt. If you did a good job, you might consider using one size smaller than the tap drill bit for the bolt and drilling the whole thing out. Once you do that the proper size tap should be relatively easy to run down the hole.
If you do break an easy out in the hole, take a center punch and a hammer and beat the ever living **** out of the easy out. They are very hard and thus also rather brittle and if you get lucky, the easy out may break enough that you can get the pieces out with a scribe. If it doesn't shatter, well you were fucked anyways right? Get out the carbide burr in the dental file and prepare to be at it a while. Or take it to a professional who will charge you a "grip" of money extra for making his job harder by filling your stuck bolt with a really hard steel core.
Get a small ball burr
![](https://www.miataturbo.net/attachments/engine-performance-56/63718-how-remove-broken-bolt-rotary_burr_ball_12mm_diameter.jpg?dateline=1357504047)
And round the top of the bolt. This makes it much easier to drill the bolt on center and reduces the chances of breaking a drill bit if the top of the bolt broke off in a jagged manner.
Use a tap handle instead of an adjustable wrench to turn the easy out.
![](https://www.miataturbo.net/attachments/engine-performance-56/63719-how-remove-broken-bolt-56c2c6fd0b826eee74c80dc59c55ba59812e1773_800x700.jpg?dateline=1357504047)
This allows for a more even pressure so the easy out is less likely to ****(
![Stick Out Tongue](https://www.miataturbo.net/images/smilies/tongue.gif)
If the broken bolt is large enough that you can get a decent size easy out in it, while you are turning the easy out tap the end of it with the hammer. This helps seat it and makes it less likely to spin in the bolt. WARNING: this is generally the step at which I have broken most easy outs.
If the bolt really isn't coming out at this point, before you break an easy out in the hole, look to see how close to centered(and straight) you were when you drilled the bolt. If you did a good job, you might consider using one size smaller than the tap drill bit for the bolt and drilling the whole thing out. Once you do that the proper size tap should be relatively easy to run down the hole.
If you do break an easy out in the hole, take a center punch and a hammer and beat the ever living **** out of the easy out. They are very hard and thus also rather brittle and if you get lucky, the easy out may break enough that you can get the pieces out with a scribe. If it doesn't shatter, well you were fucked anyways right? Get out the carbide burr in the dental file and prepare to be at it a while. Or take it to a professional who will charge you a "grip" of money extra for making his job harder by filling your stuck bolt with a really hard steel core.
#25
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For those of you unfamiliar with 60s tech big cube domestics, here is an intake valve:
![](https://www.miataturbo.net/attachments/engine-performance-56/63739d1357522551-how-remove-broken-bolt-img-20111018-00057-1-.jpg)
Puny George Washington is no match for my stock intake valve! It's literally slightly larger than the top of a RedBull can
You people keep driving your hybrids DDs, I'm gonna need the fuel.
#26
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$.02 on stuck bolts:
1. Kroil kicks *** on BP Blaster - not even close. Soak, reapply and be patient.
2. If possible, use a box wrench and tap it with a rubber BFH. Constant torque yields that horrible waxy feeling of a bolt twisting in half. Taps with the hammer (after Kroil soak) yields that beautiful 'POP' of a fastener breaking loose.
3. When 1 and 2 fail, you sometimes get lucky with a reverse thread drillbit. You need to drill a hole anyway and the reverse is at least pushing the metal in the direction you wish it would go. I've had a few come out this way but as BogusSVO said, they don't really work on rust.
Kroil is magic. I have a set of dikes that fell out of my workbelt several years ago doing a project on the side of the house. They got buried in the grass and when I found them ~3 years later, they were a ball of rust. I couldn't pull them open with all of my strength. I soaked with Kroil and an hour later I was able to pull them open - barely. More kroil. The next day I could open and close them fairly rapidly but with resistance. I hit the exterior with a wire brush and added more kroil. A week later I could open them with two fingers. More kroil. A week after that, they would fall open under their own weight. Still in the tool box today - still my favorite set of dikes. True story...
1. Kroil kicks *** on BP Blaster - not even close. Soak, reapply and be patient.
2. If possible, use a box wrench and tap it with a rubber BFH. Constant torque yields that horrible waxy feeling of a bolt twisting in half. Taps with the hammer (after Kroil soak) yields that beautiful 'POP' of a fastener breaking loose.
3. When 1 and 2 fail, you sometimes get lucky with a reverse thread drillbit. You need to drill a hole anyway and the reverse is at least pushing the metal in the direction you wish it would go. I've had a few come out this way but as BogusSVO said, they don't really work on rust.
Kroil is magic. I have a set of dikes that fell out of my workbelt several years ago doing a project on the side of the house. They got buried in the grass and when I found them ~3 years later, they were a ball of rust. I couldn't pull them open with all of my strength. I soaked with Kroil and an hour later I was able to pull them open - barely. More kroil. The next day I could open and close them fairly rapidly but with resistance. I hit the exterior with a wire brush and added more kroil. A week later I could open them with two fingers. More kroil. A week after that, they would fall open under their own weight. Still in the tool box today - still my favorite set of dikes. True story...
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#30
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For all things rusty:
If you have air, I find air hammer works like a charm almost all the time. Just hit the nut/bolt a few times with some penetrant and you're good to go.
Another trick I've been taught if you have a good impact is to shoot it CW first a bit then back out.
For any bolts/nuts I'm concerned with shearing off or don't look so great to start with, I'll usually try to fit a wrench vs a socket and then just use a hammer against the wrench to break it loose initially.
If you have air, I find air hammer works like a charm almost all the time. Just hit the nut/bolt a few times with some penetrant and you're good to go.
Another trick I've been taught if you have a good impact is to shoot it CW first a bit then back out.
For any bolts/nuts I'm concerned with shearing off or don't look so great to start with, I'll usually try to fit a wrench vs a socket and then just use a hammer against the wrench to break it loose initially.
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