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patkeefe patkeefe is offline
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Join Date: Apr 2004
Location: Ringwood, NJ
Posts: 2,850
OK, try real hard to drill a pilot hole through the center of the bolt; small diameter, maybe 1/8". Get it all the way through, you will know when you have gone through. Then, step up the size to maybe 5/16 or so. The object is to leave about 1.5-2mm of meat on the circumference of the hole. Also, this leaves a bit of room for error, in case you don't get the hole perfectly centered. The important thing is to leave a continuous annular cylinder, once it is non continuous, then the easy out won't wwork; just digs into the parent metal. Then, get a square body easy out, or a good spiral easy out...don't use the cheap ones, or you will really be f'ed.

After this, you should either be able to retap the hole, or use a Heli-coil. Heli-coil will be more than sufficient for this purpose, they are extremely strong. You can get Heli-coils at a place like McMaster-Carr. In reality, you can get full grip on four good threads, ie, if you can turn a bolt in four full turns, that's great. I prefer longer Heli-Coils.

This is all pretty easy in theory. The execution doesn't always follow suit. Good luck.
Patrick E. Keefe
78 SC
01 Boxster
Old 01-01-2008, 05:38 AM
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