Well the first few threads are stripped on the crank. Is it possible to tap out the hole? If so does anybody have the size tap needed? Also I stripped out a hole on my transmission pan. Does anybody know what size ether? Thanks

 

The trans pan is probably a 5/16s. I would go get a helicoil for the crank.

 

Crank is 7/16"-20 (Fine thread). Don't mess around, Heli-coil it.

 

same thing happened to me, the first 3 threads were mashed, but I just used a regular tap and all was well.
I feel I got lucky though.

 

you can tap the ballancer on, just be gentle and use a good thick piece of wood to help distribute the force evenly. a lot of small blocks never came with the crank drilled (i had a 350 and a 307 that were this way) so that was the only alternative . you could helicoil it also .

 

I did the same thing but I unfortunately ripped out all my threads and ended up having to retap the whole crank to a 1/2-20 bolt it was a real PIA and then I had to drill out the learg washer but now I have this great big bolt holds pretty well. I pulled mine by reinstalling the harmonic balancer so after I got done with all this I got an 8" grade 8 bolt threaded it all the way to the top and now have a great installer that I can thread all the way into the crank and use a nut to pull the balancer on. I will urge this is a major pain and only recomended if you strip out the whole thing if you helicoil it you still have to retap it out bigger and then put the helicoil in, why bother you already have it bigger and even if/when you loctite the helicoil in it may glue itself later on to the bolt and come out, so just stick to the plain bolt if you have to. IMHO
Jack

 

I messed up the crankshaft center bolt threads on my '87 IROCZ. The thread was 11mm x ?. I dont remember the pitch, it might have been 1.25mm. I simply used a 12mm tap of the same pitch and bought a new 12mm bolt.

If you have the bolt out of the engine, then just measure the bolt threads for size.

 

This is by no means my suggestion, but in '55 when the SBC was introduced, they didn't come with balancer retention at all, or an oil filter. Maybe this should be in History/Restoration......my bad!!!

 

just a WAG but i'd say you never used anything over the threads to protect them and damaged the threads with the puller bolt . good chance you can chase them with a tappered starting tap or even a regular thread chasing tap and not cause any damge. like RB said the thread is and has always been 7/16-20 for the crank bolt.

 

Yup I picked up a 7/16-20 NF tap. I'm gonna try my luck.