Bolt size

[Chevykid350]

Quick question, working on my p/u last night replacing the power steering pump and I snapped the bolt that bolts the whole unit to the front of the block and didn't have time to get it out and couldn't find the peice that broke off so I have no idea what size it is. Anybody know? It's a 78 GMC stepside with the 350 4bbl.

Thanks

 

[GMCLegacy]

im guessing it is a 3/8" coarse thread. not 100% sure though.

 

[big83chevy4x4]

its a 5/8 head do problably 7/16 corse by i think 1 1/2"