I'll spare you the details, but I snapped a headbolt off in my 6.9. Theres about 1/4 left out of the block. I've tried everything, Heating, PB, wrenching, cut a slot in it and use impact screwdriver, I mean everything I could find on the internet. From what I can tell i'm down to three options
1. Weld a nut on.
2. Ez-out
3. Drill and heli-coil

1.)I talked to a welder I know one of the best in the area. He looked at it and said he could do it but said he didn't want to because he's done stuff like that before and he's cracked blocks before and doesn't want that to happen to me. And suggest I go another route. So that option scares the crap out of me.

2.) I've read you can Ez-out headbolts, but have also read it an be a nightmare. Basically if you snap the ez-out your screwed, and its expensive to get a snapped one out. I'd feel fairly comfortable with this option but the bolt hasn't budged so I can just see this either not working or breaking the out. So this option scares the crap out of me

3.) My friend who's boat mechanic has been helping me out a bunch (borrowing tools,ect) and said he'd go with the heli-coil. He said he could help me do it and is pretty positive it'll come out just fine. But I'm just wondering are heli-coils reliable and can they hold up to the pressure in a 6.9 well (I don't want to be blowing gaskets left and right). This doesn't scare the crap out of me but it does worry me alittle.

So basically have any of you guys done either of these three options, and what would you suggest. I'm leaning towards Heli-coil, it seems the safest. I'm just worried it may not hold up.
The heads have been off for awhile and i'm really itching to get this damn bolt out and get on with my life, so any advice would be greatly appreciated.

 

I have drilled a starter hole then used a die grinder with a carbide bit to enlarge the hole till I can just make out the original threads, then cleaned it up with a tap. This has worked with exhaust manifold bolts and other places never had to do a head bolt.

 

I used to rebuild over-the-road diesels and gasser farm tractor motors. Had a LOT of broken studs to deal with. If you have 1/4 inch sticking out, I would opt for the welding a nut on first. Find a nut that just barely fits over it, even if you have to lightly hammer it on. (again, LIGHTLY) Weld it on with an arc welder. The process will actually draw some of the steel away from the side of the cast-iron bore. After it cools completely, try to turn it out without overdoing it. If it still won't budge, get an acetylene torch, heat GENTLY around the bore, say, 1 to 1 1/2 inch away from the bolt. This will expand the cast-iron away from the steel bolt. The operative word when working with heat and cast-iron is gentle. Anywhere close to red hot and it will crack while cooling, but, it is also an engine block, so it's designed to take and dissipate heat. What you want to do is make the cast-iron expand without making the steel bolt expand too.

 

i wouldnt go option 1 or 3. 1 you have to worry about getting slag pitting your block or pistons. 3 wouldnt be as strong and you would be prone to head gasket issues. get a left hand drillbit, then a easy out.

 

Head bolts are notoriously tough. They are grade 8 or better. Drilling, although an option, is tough. Carbide or better is required to cut thru them, and, you have to be PERFECT. A little one way or the other, and you drill thru your threads. Then, to get an easy-out to bite, it digs into the side of the hole you have drilled, expanding the steel into the threads even more, jamming it tighter, even microscopically. If it was jammed tight enough to break it, then you are already behind the eight ball as far as getting it out.
I've literally done hundreds like the way I described, and I have never cracked a block or caused wharpage. A few rags damp with water jammed into the cylinder bores to make you comfortable if the pistons are still in, same for any oil passages and coolant bores.
I've literally done this hundreds of times, especially with the older John Deere tractors that had the two horizontally mounted cylinders, because they were notorious for jammed studs.

 

Oh, yeah, another advantage of my method is...if it doesn't work, you have now taken the temper/hardness out of the bolt or stud, making it a lot easier to drill.

 

who ever you get to weld the nut on make shore they preheat them before welding them together othere wise you will end up with what they call a cold weld if done right it should work just fine but it going to be a one shot deal. and as far as drilling out its more trouble then its worth . carbide drill would be your only chance . that bolt would laugh at cobolt. or a bit made out of M2 tool steel at 300rpm with the right drill oil

 

Just my .02 worth. You probably already tried this, but I didn't see it listed. Have you tried Vise-Grips? Sorry, if you have already tried.

 

So If I go with the weld would i be able to leave wet rags on the block so there wouldn't be any slag getting on my block/pistons. I know the basics of welding but i'm just wondering will wet rags stop the slag.
The way i'm looking at it is like Charleswood said if the weld method doesn't work, as long as i'm careful and don't over heat, I should be ok to try the other options, and it will be easier because the temper will be gone.
I'm just wondering has anyone else actually done the weld method, and also has anyone that's done it ever cracked or warped a block. I'm just looking for as much info as i can get from as many people as i can. I'm a college student so i dont really have the money to pay for serious mistakes, if i do screw up the block.
Also I figured the heli-coil method was weaker but has anyone ever done it and what was their experience with it.

thanks for all the help so far guys

 

My question would be, why is the bolt so dman tight? If the head broke off, normally You should be able to just unscrew it by hand.

You need a Left Hand Drill extractor

Tap some new threads?

You might look around for mobile bolt removers. Most bigger Cities will have a a skilled welder that will come to Your place, and get a rod burned on the end of the broken bolt, without fubaring the threads.
I've seen it done, they Guy was there for 10 Mins. $60

 

Second what charleswood said !

 

I have welded hundreds of nuts to bolts, never a IDI head bolt but other head bolts, the success rate is high without damage, I have never damaged a block.

Yes, wet rags carefully placed will protect the goods!

It's important to preheat, get a solid weld, allow to cool COMPLETELY!!! (over the cool of the night is best)
Then heat JUST the block WHILE turning the nut/bolt!

Do not change the color of the block with heat! (I.E. Red hot)

-Enjoy
fh : )_~

 

Option #4 is to blow the remains of the bolt out with a torch. Not for someone without about ten years experience doing stuff like that though.
I saved a company I worked for about $600 blowing out a manifold bolt on a Cat C15. One of the other mechanics snapped it off, and then broke an ez-out off. I blew it out, chased the threads, and got it all set. Then the moron put in a METRIC bolt and ef'd the threads completely. I had the real fun of then drilling it out and putting in a heli-coil. I probably wouldn't be as pissed about it if his step-father didn't work in the office, guaranteeing the four-time-DUI moron a job.

 

As far as helicoil, the company I worked for had me try doing this to some old Ford 9N tractor blocks, just to see how they would work out. (We had piles of them) Bottom line, they wouldn't hold compression in RELIABLY, meaning sometimes the head would leak, sometimes it would hold. They were a low-pressure gasser 4-cylinder engine too, so, I'm reasonably certain it wouldn't hold under diesel pressures. I don't remember what the head bolt torque values were on the 9N, but they were pretty low, and we still had problems with the helicoil pulling out. It worked a little better if we coated the helicoil with epoxy and allowed it to harden, but, it still wouldn't be anything I would trust.
Let me put it this way...if I had any other choice, helicoil would be the last for a head bolt hole. If this was a antique tractor block, where they are very scarce and it is gonna be used in a parade, yeah, maybe. For a block that was gonna be used in a pickup truck on a regular running basis, no.
Actually, if I was gonna even contemplate a helicoil, I would just drill and tap the hole out to the next size larger, drill the corresponding head bolt hole out to just barely allow that bolt to clear, and go that way.

 

wet rags , a guy who know how to weld the right wat, a torch and a good hot mig welder and it should be a breeze. or if you have time spray with KROIL of PB blaster and leave it sit a day or to be for doing