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Calypso-E34

How do I remove a snapped bolt?

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There are three bolts which attach the thermostat housing to the engine on my Metro, and one of them has snapped, leaving part of it in the threaded hole. There is no part of it sticking out at all.

Anyone have any idea how to get it out of the hole without damaging the threads in the hole?

It isn't an urgent problem, as the other two bolts are holding it in position just fine, but I'd like to get it sorted and put a new bolt on it.

I'd love to meet the plonker who snapped it, and felt the best policy was to fill the bolt hole up with Tiger Seal.

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You need an eze-out screw extractor which is a hardened steel tap with a reverse thread on it.

You drill a small hole in the middle of the broken bolt and then turn in the eze-out, once it tightens it should then start to turn out the broken part.

See the attached link http://www.toolprice.com/category/screwextractors/

It is a US site but they are readily available over here.

HTH.

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Failing that, drill then tap it out.

Or.. how many threads available, shortened bolt ?

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I have said before, and I will say again, you can take your eze-out and file it in the nearest skip under as large a con as Bernie Ecclestone doing us all a good deal on the latest F1 viewing conditions.

Drill the centre out, put an appropiate square drive item in, having heated it and wd40'ed it to an inch of it's life, apply torque and turn.

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Yes you will have lost alot. You will now have a hardened and broken off item in the middle of your difficult to remove stud, instead of a difficult to remove stud.

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I have to agree with Tims.... been there and done that! If I ever have to deal with a snapped bolt now I always drill the centre out of it and tap it out, its better than dealing with a snapped off Eezi-Out :)

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I have to agree with Tims.... been there and done that! If I ever have to deal with a snapped bolt now I always drill the centre out of it and tap it out, its better than dealing with a snapped off Eezi-Out :)

Forgive my ignorance lads, but with the kit above you drill a hole in the snapped off bit, and screw one of those funny looking things in, which is supposed to unscrew the thing. What's the difference between that and drilling / tapping? What do I need to do that?

The top of the snapped off bit is level with the top of the hole.

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Tapping involves drilling to a precise diameter (the same diameter as the core of the tap (which is the overall diameter of the thread minus the pitch, so for an M6x1 thread you would use a 5mm tapping drill)). You have three options when drilling and tapping to get out a broken thread. You can either drill a smaller diameter and tap a left-handed thread, or drill the thread and broken bolt out and tap it at the next largest diameter in the measurement system you're using (inches or metric), or fit a Helicoil, which involves the previously described method of drilling to a larger diameter and fitting a Helicoil of the desired internal diameter.

If you end up getting an Easy-Out stuck in the piece of ceased bolt, you are in a worse off place than when you started, and you could end up having to get both bits spark eroded out, which is expensive and involves stripping the engine.

If it is level with the top surface, I'd first use a SHARP AND HARD centre punch to get it out by trying to hammer it round anti-clockwise.

Edited by minicooper172

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