Removing sheared bolt (aka i'm screwed) (added picture)

do you want to fix it properly or will near enough do?

do a sample drill (preferabley with a left twist drill) and identify the metal (a shaving off of the head will also do) If its steel an easy out will get it but not if its brass.

selection of the allen key for the allen key to work is critical, if need be redrill the bolt to suit the size of the allen key, you can buy an extraction tool that works on that principal and the good kit comes with left hand drills (so do good narrow taper eazy out kits)


Drilling and tapping whats left in there to suit a different size bolt and then working the face to allow it to seal will be the easiest solution that doesnt cost a bundle and one of the professional call out type guys (as previously mentioned) will be the easiest best solution but with the highest cost.

Quote:

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Originally Posted by whitakerb

Anyone know the size of the bolt. if its German it probably metric. Its a hollow bolt which means it will be very easy to drill out. You need to find out what size the bolt is. Then you need to drill it out with the Tapping drill required for the bolt. NOT THE CLEARANCE DRILL!. Once you do that the remaining thread will pretty much fall out. For example:

If it was An M10 Bolt.

OD is 10.0mm
Pitch (usually) is 1.5 mm

OD - Pitch = 8.5.

Drill out with 8.5 mm drill bit.


EDIT:
As lochie said, build up to the drill size required, don't just drill it out in one go.

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There are four pitches of 10mm threads in relatively common use. Tapping drill for all metric threads is diameter - pitch.

I'll keep this short...

left hand bit now stuck and sheared off too.

your not having a real good run are you....

freezenrelease and a pair of needle nose pliers.

I don't suppose you can warm it up a bit? Probably too many things around there that are not compatible with naked flames. Last resort. Take the head off and take it to a machine shop with an electronic discharge machine. Have you tried squirting it with Chemsearch Yield?

I can't remove the head (being a SOHC I have NFI how to do it and retain timing) so I'll have to start considering the options. Those being find an MB mechanic or give my mobile diesel mechanic a go.

Quote:

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Originally Posted by B92 8NW

I'll keep this short...

left hand bit now stuck and sheared off too.

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I'm guessing you have already tried to twist the drill bit out with some long nose pliers.

When I was a 1st yr apprentice i broke lots of drill bits and taps. Big hammer + Centre punch will shatter a broken tap or drill bit. Give it a shot then pick out the bits. I think you have gotten past the stage where it can be done without expecting swarf ending up in the head. Once you do that i suggest drilling it out as I mentioned in my previous post, but build up very slowly in drill bit size. Better bet would be to use a 240 volt drill rather than the battery drill as it will have a higher rpm and will cut much better...

If you don't feel confident, take it to someone who is but I think they would only do the same thing..

Persistence is the key.

Good luck!

could you put a left hand thread self tapping screw in and use that to undo it