Block cracked starter mount hole, fixable?
 

Started out with a bad starter but it tested ok on bench so in the process of searching for a problem some guy at local parts store said he could test my crank position sensor and he did and said it was ok, eventually just tried changing the starter to find it was the problem all along but ever since it was starting extremely rough and started cracking the nose cones off of starters, after changing plugs, wires, cap/rotor still starting hard and breaking starters. After no-one could figure it out I was searching online, found this site and discovered any time you have a crank sensor out that you must perform a CASE learn procedure. So- I take it to a shop with a tech II and tell them what I need. They tell me to leave it, after I explain I really didnt want to shut it off and break yet another starter they said I'd have to leave it and give them, the key - so I did, 3 hours go by, I call and the guy says "it wont start, the starter doesnt engage" I go over, pull it off to find that the outside edge mounting hole is cracked and letting the starter move out so it cant engage.
My question is, is there any way to fix or work around this or will I have to replace my whole engine now? I asked a different shop and they didnt think welding and tapping would work.
Gotta say Ive been through hell with this thing for weeks and all because of some store guy having me take the sensor out, not too happy! Cant help but wonder what went on at that shop for 3 hours with it also!

I'm wondering if that hasn't been your problem with the starters all along. There could be something else causing it to start hard, but a hard starting motor shouldn't be snapping starters left and right.

About the only option see for you is to drill & tap the block deeper and use a longer bolt. You have to be very careful not to drill too deep and enter the water jacket. Beyond that, a new block.

From all my online searching, all I could figure out was that not having the CASE learn procedure done after I had the crank sensor out was causing the engine to backlash at start-up. The mounting hole in the block definitely wasn't cracked before today or I would have seen it during one of the changes.

If you didn't replace the CKP sensor and just removed it and put it back in, the old correlation value shouldn't have been far enough off to cause any problems. I have all out replaced CKP sensors before and never had a CEL result or any bad running. Still performed a CASE learn though. I really doubt that the removal and reinstallation of the CKP sensor is what is causing your starter to break.

It could have been cracked and you never noticed it, but still enough to allow the bolt to loosen up and not hold the starter firmly. Either that or you have a serious problem with the flex plate as well. The only time I have broken starters is either when the bolts loosened up or there was a problem with either the starter or the flex plate. They are built to handle a certain amount of kick back.