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Old 06 February 2010, 21:44   #1
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Removing sheared bolts

How can I remove two cheared bolts from my engine block? They hold the casing for the thermostat. They unscrewed easily then bam! They sheared. Any ideas? I think I may have to take it to engineer. Theres not much thread left either 2-3 threads max.

Thanks.
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Old 06 February 2010, 22:14   #2
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Have you tried bolt extractors yet?
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Old 06 February 2010, 22:58   #3
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Think this is how they do it at Kwik-Fit!
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Old 07 February 2010, 01:00   #4
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You would probably be better taking it to an Engineering workshop. Chances are that if the bolt was so siezed in the first place, that the stud just sheared off when you tried to remove it, then a stud extractor probably wont shift it. It may have to be drilled out & re-tapped. But a word of warning, if you do try a stud extractor, and then Shear that off in the hole, then that causes MAJOR problems! Because they are harder than a drill bit and cannot be drilled out. Best left to guys who are doing it every day
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Old 07 February 2010, 07:51   #5
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Originally Posted by Robbie Diesel View Post
You would probably be better taking it to an Engineering workshop. Chances are that if the bolt was so siezed in the first place, that the stud just sheared off when you tried to remove it, then a stud extractor probably wont shift it. It may have to be drilled out & re-tapped. But a word of warning, if you do try a stud extractor, and then Shear that off in the hole, then that causes MAJOR problems! Because they are harder than a drill bit and cannot be drilled out. Best left to guys who are doing it every day
I'll second that. Easy-outs very rarely work. Take it to a engineer.
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Old 07 February 2010, 09:52   #6
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Originally Posted by Samz9090 View Post
How can I remove two cheared bolts from my engine block? They hold the casing for the thermostat. They unscrewed easily then bam! They sheared. Any ideas? I think I may have to take it to engineer. Theres not much thread left either 2-3 threads max.

Thanks.
They were nearly out then?

I agree with NOS, Easy outs rarely work....
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Old 07 February 2010, 10:42   #7
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Typical! Just thought Id check the themostat quickly and now i've got myself into a world of s**t! Nevermind, Im sure it can be fixed.

Thanks for your replies.
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Old 07 February 2010, 11:04   #8
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If they were nearly out and you can get some grips on the stud, you could try gently winding it back in and out. Don't get carried away though. If you're not sure then take to it some one who is...
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Old 07 February 2010, 11:10   #9
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Can you post a photo showing how much is protruding and how much is left to go? There are a few things you can try that would not make the situation worse.
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Old 07 February 2010, 11:13   #10
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Easy-outs do work, I've used them countless times and never had a problem. However they don't always work and aren't always the best tools for the job and in inexperienced hands do break off as suggested leaving you with more problems. A blow torch and easy-outs are also a great combination.

However!

If you are inexperienced with such things and have tried and failed with all the easy things like mole grips, etc. I would suggest a trip to a local engineering shop, they might be able to weld some studding or a bolt to the end for the sheared stud and extract it that way. Otherwise it's a drill out job and Helicoils.
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Old 07 February 2010, 11:15   #11
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It depends how tight it is, but I have removed a sheared bolt in the past with a centre punch and a hammer.
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Old 07 February 2010, 11:46   #12
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if there's any stub showing drop a nut over it and puddle weld the middle in, before it get cold try winding it out
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Old 07 February 2010, 12:08   #13
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if there's any stub showing drop a nut over it and puddle weld the middle in, before it get cold try winding it out
We can't get that spanner to you quick enough
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Old 07 February 2010, 12:35   #14
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Upon weighing up the situation I may aswell get it looked at by someone who knows what there doing! (not me haha). Thank you for all your replies! It is much appreciated.

Thanks Guys and Gals!
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