How to extract a snapped head bolt?

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mynameismud76

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Hi guys,

Snapped a head bolt on a 4 bolt head. There's nothing poking out..it's quite someways down there.

I'm thinking about drilling it out, but doubt I can do it without knackering the thread.

There's this tap bit that unscrews a screw as you tap the thread..what's that tap called?
 
Hi Admins/Mods,

Sorry, I've listed this thread in the wrong place. Please could you post this under Engines section?

Cheers =)
 
before the mods shift you.. it's called a stud extractor. problem is that the head bolts aren't very big, so you may struggle.

if you can find any left fluted drills, use one of them to drill the pilot hole.

I know that 4 bolts is better than 2, but you may be OK with just 3 so long as you gt the correct torque on the bolt heds.
 
easyout/studextractor same thing.

but like BTBs link says, pay some dcent money for one, probably about £10 minimum for a small set.

there is a set in screwfix for £10, but it's probably made out of cheese like al of their cheap stuff. http://www.screwfix.com/prods/20084/Van-Car-Accessories/Mechanics-Tools/Stud-Extractor-Set-8-Pc?cm_mmc=GoogleBase-_-Datafeed-_-Van%20and%20Car%20Accessories-_-Stud%20Extractor%20Set%208%20Pc#

a better buy may be the Clarke set at machine mart. still a cheepy set, but should be OK for diy stuff (it'll only be a steel bolt in alu case so shouldn't be stuck too hard unless it's cold welded itself in there) http://www.machinemart.co.uk/shop/product/details/cht526-12pce-drill-screw-extractor-s/path/screw-bolt-and-stud-extractors
 
LOL, I don't feel that confident..But I'm gonna whoop the head off and see if there's any of the bolt poking out of the crankcase. If there is, it may be a lot simpler than having to use to the easy out.

Cheers BTB =)
 
You might have better luck using a left handed thread tap?

Tend to be better quality than cheap stud extractor and you can get some decent small sizes. I would also try to heat the head up right before you actually try to draw it out. Some Loose-all or something like that down the hole for a while too is a must, specially as something must have stuck the original down there for it to snap. :mad:

These guys have just about anything and in our kind of sizes without costing the earth: http://www.tracytools.com
 
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