Got the old cylinder head off (finally) and almost ready for the new one. Next road block.

One of the cylinder head bolts (that hold the cylinder head to the block) broke right at the block. The head itself came off without a hitch.

I know the usual way is to just drill in the middle and use and extractor bolt to remove it. However, I have just not acquired that skill for some reason. I don't know if I was using the wrong type of bit or what so any help is appreciated. Here is a pic, the bolt is in the yellow circle (pretty sure you' would figure that out anyway).

 

WOW....horrible.....I would try a good bit for this job and a nice drill...definitely oil on the bolt...constantly....olive or any freaking oil to lube as you drill or tap...

personally have never done this...

how about a crazy idea?

spot weld an Allen wrench a bit smaller than the bolt itself and just twist it out of there...? too crazy
or no welder? use a car battery and jumper cables..youtube it

hope it helped or realized that I am crazy

 

I wouldn't try hte spot weld thing, way too high of a chance of welding the bolt to the block.

thats a hardened bolt, so its not going to be easy to drill out at all. probably need to use a drill press, with a very small diameter bit and a lot of cutting oil (NOT vegetable!), then a larger bit and a larger one again. or maybe EDM (electro-discharge-machining), which you'll need to find a guy who has this stuff and does exactly this. EDM would eat out the bolt then you'd pick out the remaining threads and use a tap to clean up the threads. or drill them out entirely and put in a time-sert.

 

Looks like it is time to develop that skill now. Necessity is like that sometimes. Here's a tip. Yes, the head bolts are hardened steel but they are certainly drillable. As it is a relatively large area, and wide open, don't start with too small of a bit. Nothing quite as fun as drilling through a broken drill bit the same strength as what's in your drill! Now that the head is off and the bolt broken, the remaining stub may actually be relatively loose. Some PB Blaster soaking and then heating or "cooking" it in can help. When they have been above the block a bit, I've been known to cut a groove in the top for a slotted screwdriver. Good luck...let us know how it turns out.

 

You need to get your hands on . You may find that giving the bolt stub a few really good whacks with a punch will break it loose. Then a reverse drill bit in the magnetic base drill press will spin it out for you.

Oh and the absolute best penetrant, better than all the commercial products, is a 50/50 mix of acetone and automatic transmission fluid.

 

that acetone and ATF thing has approached mythological status.

do you know the guy who did the original tests that were published about 20 years ago in an amateur machinist magazine actually used TCE (now banned) and power steering fluid? he admitted it in a letter to the editor. He wrote it u as Acetone because he didn't want to encourage the use of highly toxic TCE.

further, modern synthetic ATF apparently won't even mix well with acetone. If you can find soem original formula Dextron III, go for it, that works decently.

meanwhile, I'll stick with Kroil.

 

For the price of the drill he could buy a couple more cars!

 

Wow, some interesting replies. The $1200 drill press would be nice, but wife would probably divorce me (can be looked at as good or bad, lol).

There is a couple 1/16ths of the bolt above the head of the block so the slot in the head might be a viable option. My only concern there would be getting into the block itself. Would that be an issue if there were some nicks or possible groove from the Dremel in the block, the gasket wouldn't be compromised when replaced would it?

I figure that if that didn't work then the old fashioned drill bit down the middle, a starting notch would pretty much be there already.

Good thing I got a new can of PB Blaster.

I won't get to work on it until Friday or Saturday but I will keep you posted.

I'm posting pics of the head removal shortly.

 

He doesn't have to buy one.

It's difficult to center drill a broken bolt with a handheld drill. Every one of the OP's threads contains some kind of self-inflicted disaster. He'd be improving the odds in his favor if he used the proper tools.

 

You may be right about the TCE but the acetone/ATF mix was tested by a magazine as recently as 2007 and came out ahead, though apparently they used power steering fluid instead of ATF. I use Kroil myself but the OP may not want to wait for Kroil to be shipped as you can not buy it retail. Liquid Wrench is almost as good as Kroil for a fraction of the price.

I believe it's Dexron not Dextron.

 

thats the article. google the authors name and follow threads for his admission it was tce too. guess it was 5 years ago not 20.

our local indie parts store sells kroil in aerolsol form.

right, dexron, typing on this tablet is driving me nuts

 

My 240 has now made it personal!!!

Had the broken bolt in the block, got some cobalt drill bits, bored right into the middle nicely. PB Blaster for good luck. Bolt extractor inserted. SNAP.

Son of a B!&@#!!!!

 

Don't give up man...."You must be victorious Not only for you, but for all of us!" The community demands it, Needs it, supports it," Feel the Vorce!!!!!!

Try a Bosch drill bit or Milwaukee and repeat the process.
How deep did you insert the extractor?
Show some pics

 

Did you hit the bolt hard with a punch? Use heat?

I can tell you what to do next if you like.

 

I tried hitting what was left of the extractor hoping it might break up into pieces but no such luck.

I've gone a somewhat unconventional route but it seems to be working although I won't have time to finish until Friday or so.

I got a Bosch Blue Granite Carbide drill bit, they're actually for hammer drills and concrete but if they can go through rebar what the heck. I cruised through about half of what was left of the bolt so far pretty quickly which was about 6 times farther than I had gotten. I think it was dulling so I ordered some off Amazon, 5 pack was $5 vs. about $5/each at Home Depot. Since I can't get to it until Friday so no big deal.

I should be able to bore right through to the bottom and then getting it out should be a piece of cake (which I of course just jinxed).

I'll keep you updated. I am at least encouraged now vs. kicking and screaming.

 

worse case, you drill out out oversize and use a time-sert.

 

I like the bit you chose. I used to use them to anchor pipe from concrete ceilings/floor...sometimes we would hit 1/2 inch rebar on 16 inch floors and would need to use these drill bits from Bosch...ate right through the rebar. For the record, we were only allowed to bore through on certain locations as you compromise the purpose of the rebar.

 

Seem to have hit an impasse. Blue Bosch bits are working pretty good but obviously dulling is an issue. I am about 1/2 down the length of the bolt that is left. I did pick up some lefty drill bits but can't seem to get them to bite.

I am thinking heat might help the bit get some traction?

I will not let her win!!! I will prevail!

UPDATE: She is just toying with me again. Finally got a small left hand bit to bore through the center, excitement!! Tried the next size up, but wouldn't make the hole larger.

So like a dumb @ss, I tried another easy-out, you can guess the rest.

 

Finally had some extra time to work on this thing, she will not win!!!!!

I've certainly made a nice mess of it so far. Two broken severely misnamed "easy outs" and a big mash of twisted metal and still the bolt is still in there.

So, I think it's time to just drill the thing out and use a helicoil/timesert to fix it.

I haven't ever done one where the bolt was still in the hole, I can't get the damn thing out now how am I going to get it out to put the insert in?

Help, I will not lose!!!!!

(thankfully this isn't the daily driver lol)

 

Many years ago, before I knew of EZ outs, I would drill a small pilot hole in the center of the bolt head. Then I would progressively use each bit in the set until the bolt was only an mm or two thick on the walls and then bring it up and out with a pocket screwdriver and various picks. Centering the initial bore is the simplest way so that the entire circumference of the bolt is removed equally; often no insert is needed as the threads are unscathed. After breaking a bit or two off in the bolt, drilling becomes a bit sketchy and thrashing the original threads is pretty much a given...but not always. Take your time...you'll win.