bradthebold

Somehow ran into an issue on something this easy, but I was removing the alternator mount and the top rear bolt came out 1/2" and then get very hard to turn. I didn't want to break anything, so I sprayed it with PB blaster for a while and screwed it in and out and it felt a lot better. Right before it came out there was a crackle and it led to this. The bolt has some flattened threads near the end. What should I do to fix it?

V2Rocket

youll be ok with 3 good holes..
that said you could remove the broken parts and smooth the cracked surfaces down (to prevent further cracks) and see how deep the threads go - maybe still able to get some thread bite with new bolt.

bradthebold

Thanks, that's what I was hoping. I got it smoothed up and it looks like there's plenty of thread left, I'll just have to run a tap through it to be able to get a bolt in.

ekoz

LOCTITE 28654 Stripped Thread Repair Kit

Never used this product but talked to some guys I work with about stripped bolt solution and they have used it on their tractors with success. Fortunately I did not need it. Not the exact solution for your problem but possible option.

Tom M'Guinn

From the sunlight, I assume it's out of the car. If so, a good tig welder could patch it up. You'd likely need to helicoil it (which you might want to do even if you just leave it), but welding would be the strongest approach. Or this stuff...

KevinGross

I agree with welding, followed by a Timesert (or Helicoil altho I've not used them).

Tom M'Guinn

In aluminum, helicoils are stronger than the original threads, and I imagine timeserts are stronger still. With a helicoil, you get a second bite at the apple with a timesert if you screw them up (and maybe again with a bigsert). My car is about 1% helicoil by weight.