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Discussion Starter #1 (Edited)
One of the water pump bolts sheared off flush with the surface of the block. I need some advice on how to tackle this problem, please.

It's visible at about the 3-o-clock position here:

 

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I'm guessing that's your gasket leak where that bolt failed

See if your local hardware has an 'easy out' , it's like a tapered drill bit but goes in anti clockwise which drills into the stub of the bolt and allows you to pull the bolt out.



Usually the bolt stub comes out in the drilling process of putting the 'easy out' in

Flush with the surface of the block is nasty , hard to use any other method than the easy out other than drilling oversize and re-tapping which isn't ideal.


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Your going to have to pull the radiator out to get in there and I suggest removing the bonnet/hood.
 

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Discussion Starter #5
Radiator is already out. I have had terrible results with easy outs before but I guess that's the only option here. Thanks for the input.
 

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Or you could try an impact screwdriver but you don't have much space in that area , depends on how corroded the rest of the bolt is.

I've been lucky on a couple of occasions to tap them out like that without having to use an easy out
 

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Discussion Starter #8 (Edited)
I drilled out the remainder of the bolt today. I was surprisingly well centered initially, though the final hole that I'm left with is not quite the same as what was there to begin with. Upon further inspection of the bolt, it was not the correct / original bolt, so this may have contributed to it seizing in the threads.

I am going to tap the hole to M7 size. I'll use a heli-coil if tapping is unsuccessful. I'll also be using "The Right Stuff" sealant for extra insurance against leaks.

I appreciate everyone's input and advice.
 
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