Broken rusty head bolt...ideas?

oilburner22

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I just finished pulling off both heads last night to get them worked at the machine shop (I checked he knows IDI heads) but while I was breaking loose the head bolts on the passenger side one of the external (outside the valve cover) bolts threads were so rusty when I gave it one last good tug with my long half inch ratchet I got a broken head bolt...now the issue is its rusted and seized in there but to my advantage about 1/2" is still exposed out of the block. I soaked it in PB blaster twice last night and I'm gonna repeat that tonight but I feel like any kind of extractor is out of the question. I have a bad a$$ snap on air hammer and an impact driver ( hand held thing you hit with a hammer to extract screws and such) so my first idea is to chisel a good groove in the top of it and try the impact driver...or maybe trying to flatten two sides and use vice grips...any advise with extracting these would be greatly appreciated!
 

FarmerFrank

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Drill a small hole in it first.

Heat just the bolt red with torches.

Go get a beer, sit down and drink it. 2 if it's been a bad day.

Now that it's cooled off keep soaking it and grab it with some good pliers.

If that doesn't work I'd weld a washer to it flush with the block, then weld a nut to the washer and the rest of the stub.

Go get another beer to let that cool off.

If that doesn't work then you really have problems.




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oilburner22

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I keep an 18 pack of Budweiser:cheers: handy...I would think to heat the block to expand it away from the bolt (like on anything else, that's just how I was taught) but I guess that's worth a shot. Just trying to avoid a torch or a welder because I'd really really prefer not to have to pull the block out for any reason...thinking I might have to because I think the oil pan is leaking and I hate leaks-cussand leaks were the main reason for this tear down. I'm pretty much resealing everything, replacing the fuel system, probably gonna do a facet and coolant filter, and adding a factory turbo from a 94. Oh and the radiator was busted.
 

FarmerFrank

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If you heat just the bolt the expanding and contracting of it with the hole drilled in help break the rust free.

I've had better luck in the past doing that rather than heating the surrounding area. Less chance of weakening the block in that area too


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icanfixall

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Even though this is the outside area of the block I feel its a bad idea to heat it up. I also feel the drilling a hole thru the bolt is the better idea. Measure a bolt and figure out how much you need to drill the broken piece. then grind the top of the broken bolt to get a flat area. then center punch it and drill say an 1/8 inch hole in the bolt. Then try a 1/4 inch drill bit. Remember this is a 1/2 inch shank bolt. Aerokroil is a much better penetrant for this kink of issue. a small pipe wrench will grip the broken bolt. Might try hitting the exposed bolt to loosen the rust too. How much of the bolt was actually rusted thru? Reason I ask is might be easy to grab the broken bolt and turn it out once you get a good grip on it. Sadly rust creates about 50,000 lbs of expanding force when it grows in this type of break. So releasing the tension by drilling out most of the bolt helps more than you know. Turning the broken bolt both directions breaks loose the rust also. Nice idea about cutting a slot in the top and using an impact to break it loose too. Same thing here too bout turning both directions to loosen the rust.
 

IDIoit

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I had this issue on one of my blocks.
I ended up heating it up with a propane torch, cant get it super hot that way,
I used a pipe wrench after heat, and while trying to unthread it, I used a flat bit on my air hammer and hit the top of the broken bolt.
had 100% success rate.
 

oilburner22

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I pulled the block out last night so that I can clean it, easily reseal everything (maily the oil pan) paint it, assemble the long block and reinstall it. Also, it will make removing this busted head bolt a lot easier. I will update when I get a chance to work on it some more.
 
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