Godd*mn alternator bolt

[PercyTheAce]

So I’ve had this issue happen at least 3-4 times now in the last 4ish months. The front alternator bolt that the alternator hinges on keeps snapping off and I can’t figure out why. It shears off flush with the mounting bracket, and I’ve tried replacing it with a shouldered bolt that’s stronger than the original bolt, I’ve even tried a bolt that matches the original bolts hardness. And yes I’ve double checked the torque spec, it’s only around 5 ft-lbs which is what I’m tightening to. I’ve even swapped to a different bottom mounting bracket. The only other thing I can think of that it might be is the alternator casting is bad causing it to be misaligned, but I’d been running that alternator for about 4 months prior to having any issues. Anyone have any ideas?

[banzai510(hainz)]

Is your 210 lowered down almost to the bumpstops?

 

My 510 did this all the time.when I had the smaller bolts in there. usually the frontbolt.car was slammed in front and bumpy roads to work.Always fixing it!!!!!!!!!!!!!!!Allways!!!!!!!!!!My life was better when I really had the proplem fixed.

 

I found a spare 510Alternator mounts(lots of them) and had a machine shop drill it out. I think 3/8s bolt.  You can use a nut on the end or what I did on one is drilled out the back ear of the alt and put a keensert so Idint no have to use a nut.But remeber the stores like Napa might take them back as a core for rebuilding.

Later Datsuns with the L motors went to a bigger bolt later and did not have this proplem. I dont know A motor but assume the same

Edited July 15 by banzai510(hainz)

[PercyTheAce]

It hasn’t been lowered, it’s sitting at stock height on stock (albeit probably tired) suspension

 

The bolt size that’s in there is a 10 with 1.25 threads I think? I can’t remember off the top of my head. I’m starting to think it might be a shitty casting on the alternator since it’s an oreillys remanufactured. It’s just odd since I’ve been driving a series cars for the last 7 years and this one in particular for the last 3 years. This is the first time I’ve had this issue

[Stoffregen Motorsports]

Is this a cast lower bracket? If yes, drill all the way through it and use a long bolt with a nut and a lock washer. Use an old head bolt and you'll never break it again.

Edited July 16 by Stoffregen Motorsports