True, always feel for slight movement, and try not to superman the broken bolt out on the first try.

Also how the hole is drilled can make or brake an ez out removal.

Oh a FE Ford!! How I love/hate those heads!

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

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/attachmen...ine=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/attachmen...ine=1357504047
This allows for a more even pressure so the easy out is less likely to cock( :p ) 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 shit 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.

Exactly the same thing on my car.

I can"t believe how that battery bolt snapped off!

D2TE. I briefly considered putting Cobra Jet sized valves in it, but then I realized "this is a rusty ass truck, stop spending money" and went with stock size replacements. It never ceases to amaze me how ENORMOUS the ports are on these heads. EBay supplied me with an ugly and well loved Performer RPM intake and I found an Autolite 4100 at a swap meet for $20. I ditched the "emissions compliant" points distributor for a recurved Duraspark and an MSD box. It now pulls like a goddamn freight train and probably gets 9-10mpg... up from 5-6mpg.

For those of you unfamiliar with 60s tech big cube domestics, here is an intake valve:
https://www.miataturbo.net/attachmen...1&d=1357522551
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.

$.02 on stuck bolts:

1. Kroil kicks ass 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... :party:

Kroil also smells better than PB and gets bonus points because it works on firearms as well.

I use Kroil a LOT at work with airplanes. it is a life saver. Also when kroil evaporates it leaves a little lube rather than drying up like WD-40 does.

Too many people assume because it gets rid of squeaks that WD-40 is a lubricant. That couldn't be further from the truth.

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.