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Simplicity_728

Broken cylinder head bolt

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steve-wis
Nick, Many ways to remove broken bolts. You can drill a hole smaller than the bolt in the center and try an ez-out. If you do that, I suggest lots of good penetrating oil and some heat first. You can also carefully drill a hole in the center the same size as you would drill if you were tapping a new hole, then carefully clean out the threads with a tap. If you have already drilled a hole, and if it isn't on center (which often happens) the best way is to take the block to a machine shop and have it drilled out- will cost you a few bucks but you will have a usable hole. Some guys weld either a nut or something similar to the broken bolt and remove them that way, but I haven't had alot of luck with that if it is broken off flush. Others will give you their opinions, and of course, this is only mine. Good luck! Steve

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Burntime
Not neccessarily a head bolt but I have welded a washer or nut to a broken bolt and used a screwdriver thru the washer, a crecent wrench on a washer, or a wrench on the nut that was welded. I usually weld it on and then hit it with penetrating oil to quench it. So far so good. Good luck, it never fails that its either the first or the last one that goes!

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MrSteele
I have drilled them, then tapped them with a left hand thread tap. In effect, when you tighten a bolt into the new threads, you are loosening the bolt that is broken. Sometimes, a left hand drill bit will grab a blot and bring it right out. Just never forget the penetrating oil, first.

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Simplicity_728
I tried the chisel metheod and got half a turn and thats its. I drilled out the center alittle more and tried an easy out, but all that does is grab then spin. If it helps this happend when I was tightning then down after putting a new head gasket in. And I was using a torque wrench

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HubbardRA
Before installing heads, you should always run a tap into the holes to clean up the threads and run a die down each bolt to do the same with them, then lubricate the threads before installing the bolts. That way you remove all dirt and burrs that may cause a bolt to hang up. You will also get a much truer torque reading.

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moparharn
"lubricating" the threads should be done with something that is not too slick. Maybe an anti sieze or wd-40. While your torque readings will be more consistant, your tension will increase substantially, and this could result in excessive yield or failure. A higher friction lube would be fine. I do this for a living and thought I should chime in. Bill

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steve-wis
I always clean mine with a tap and use anti-seize on them. Back to your problem, if it is moving a half turn, keep oiling with a good penetrating oil and working it. As far as easy outs are concerned, there are a few different styles. The ones I have the best luck with as far as grabbing good are the ones with left hand flutes and teeth on the edges, but these seem to be the weaker ones and more likely to break. The ones with the straight tapered flutes that you drive in with a hammer are stronger, but don't seem to grip as well. Drilling a larger hole in the bolt might help you too, it will relieve more of the metal, but then you will need an easy out to fit the bigger hole. Also, heat almost always helps. Again, my best fix is to drill on center till you get to the tap drill size and then clean out the threads carefully with a tap. Keep working on it, you will get it out. Steve

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