broken flexplate bolt

[76 bumblebee]

ok I have searched and the damn search button and google don't like me. what I have is a 351W with a C-4 transmission with a dana 20 tcase in a 76 bronco. I took the transmission and transfercase out and found that one of the heads of the flexplate bolts was broke off. it didn't break off flush. there is a little less than 1/4" remaining out. also the other 5 bolts had the last 3-4 threads stripped at the end of the bolt and were hard to remove all the way out. I tried an easy out tool that fit over the remain bolt with no success.

two questions:

1: looking for an opinion of welding a nut to the remain part of the bolt. I understand about trying to weld on the end of the crankshaft. if grounding to the nut and not to the block would that be okay.

2: what would be the issues of just leaving that one broken bolt and 5 new flexplate bolts.

thanks,

 

[Hubba]

If 5 won't hold it 6 never would.

 

[Broncobowsher]

I am thinking that someone used flywheel bolts on your flexplate. How long is the bolt? 7/8" or 1"? If all the bolts are damaged something is really wrong. Was the bolt head anywhere to be found? It may have broken and whoever put the engine in just went F-it. Or did the bolt head pop off?

http://www.youtube.com/watch?v=jzCMoDDSF6o at 9:55

 

[strokers]

I don't see a issue with welding a nut onto it . it won't take long to fill in the Nut so not much heat transfer. I would be more worried about the seal.

 

[Explorer]

I would place your ground on the flexplate at least. Just good welding procedure to keep ground as close to weld as possible.

 

[76 bumblebee]

The head of the bolt was nowhere to be found. It had been broke for a while. The bolts that came out were definitely too long. I took apart another transmission I had at the house and the bolts holding that flexplate were much shorter. Thanks for the idea of using the flexplate as the ground. I was wondering how to ground the nut so the current wasn't going thru the block.

 

[76 bumblebee]

Thanks for the help. The bolts that were used were definitely too long. I pulled another engine and transmission apart at my house an ur had much shorter bolts (with one of them also broke off). I was wondering how to ground the nut so the current wouldn't be going through the block. Thanks for the flexplate idea.