Question: Broken alternator bracket bolt

[JMILL]

It sucks, but a bolt from the alternator bracket broke off in the cylinder head...Can't get stub out. Probably need to remove that cyl. head & take to machine shop. To pull the head do I need to pull the intake manifold? Should I do a valve job on removed head (but not on the other head)? Engine has >120,000 miles but runs quite well. Should I remove BOTH heads and do valve job? Should I have entire engine rebuilt? Appreciate any comments. Thanks. ad

 

[c5vetter]

personally, if it ain't broke...........

 

[JMILL]

Thanks...

personally, if it ain't broke...........

Been around the block enough to think you may be right...I'm leaning to just pulling THAT head, taking it to machine shop and letting them deal with the stub. No valve job, no other head work, etc. "I'm getting too old for this Sxxt". trying to decide if I even want to do that much work. Car is drivable at low speeds with only 2 of 3 bolts holding alternator, so I could drive it to someone to do the work...It's ONLY money!

 

[gmjunkie]

Been around the block enough to think you may be right...I'm leaning to just pulling THAT head, taking it to machine shop and letting them deal with the stub. No valve job, no other head work, etc. "I'm getting too old for this Sxxt". trying to decide if I even want to do that much work. Car is drivable at low speeds with only 2 of 3 bolts holding alternator, so I could drive it to someone to do the work...It's ONLY money!

If it was me,I'd just drill the bolt out with a left hand drill bit!
Souldn't be that bad on a 67 BB or SB car!

 

[LLC5]

If the bolt is not cross threaded into the head, you should be able to remove it. Try a left handed drill bit like Junkie stated, and if that doesn't work then drill a hole in the center (center is critical) of the bolt and try to use an easy-out which is left handed thread. Some heat from a torch may be needed also, but as long as the bolt is accessible it can be removed. If you don't want to try it yourself (you can make matters worse if the hole is not centered and straight) find a independent repair shop that has been around a long time in your area (your looking for an older tech that knows what he is doing, and has done many extractions before and it doesn't need to be on Vettes, just bolt extractions), drive your car into them and let them take a quick look at it and see what they would charge. Some special tools can help, like an angled drill and a torch. Good luck with it.

 

[JMILL]

The Swamp Was Finally Drained.

Thanks to all who gave advice...I had decided to have a machine shop extract the bolt by taking the single head to them. After reading these texts, I figured I'd try one last shot. I bought left handed drill bits (didn't know they existed) for the extraction, but the problem was that I'd broken off a piece of regular drill bit 3/32" in the bolt stub. I ended up buying these diamond coring bits (below) from Amazon. Paying strict attention to going slowly and keeping water on the drill, I succeeded in coring out the broken drill bit within the bolt stub. The hole was off center (damn) but good enough to get an extractor to bite and remove destroyed bolt stub. I damaged the deep end of the hole's threads on one side but a regular bolt now still holds well! YAY! These drills are cheap and are the greatest thing since sliced bread that I'd never heard of. BUY SOME for your tool chest bag of tricks! (Hardened steel is Mohs 7.5 , while diamonds are Mohs 10.0)!!!!

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Sold by: eToolscity
$6.99
Condition: New

 

[Tom Bryant]

They are cheap enough. It might be a good idea to have these in the box.

Tom

 

[LLC5]

Thanks to all who gave advice...I had decided to have a machine shop extract the bolt by taking the single head to them. After reading these texts, I figured I'd try one last shot. I bought left handed drill bits (didn't know they existed) for the extraction, but the problem was that I'd broken off a piece of regular drill bit 3/32" in the bolt stub. I ended up buying these diamond coring bits (below) from Amazon. Paying strict attention to going slowly and keeping water on the drill, I succeeded in coring out the broken drill bit within the bolt stub. The hole was off center (damn) but good enough to get an extractor to bite and remove destroyed bolt stub. I damaged the deep end of the hole's threads on one side but a regular bolt now still holds well! YAY! These drills are cheap and are the greatest thing since sliced bread that I'd never heard of. BUY SOME for your tool chest bag of tricks! (Hardened steel is Mohs 7.5 , while diamonds are Mohs 10.0)!!!!

​

Neiko Heavy Duty 5-Piece Diamond Dust Hole Saw, Tile Glass Marble slate Tool
Sold by: eToolscity
$6.99
Condition: New

Good job! It sometimes takes a lot of patience to do it correctly.

If you haven't already, blue locktight would be a good idea on the new bolt.

 

[JMILL]

Blue locktight

That's a great suggestion. I'll do it. Thanks again...