Broke. Thermostat housing bolt

You were lucky to be able to retrieve that broken piece. Take the other bolt, try it for size. If it fits, and probably will, go to an auto parts store or hardware and get one that matches. Get the higher grade bolt to replace it....maybe replace both.

Yeah it was just far enough to get the vise grips on it. It was three of them so I got two left but didn’t want to put it back together with just two bolts. Where you think I should go parts store or maybe Lowe’s

Either one. Anywhere they have a bolt selection. Torque them down evenly/gently as those thermostat housings are brittle junk metal. Good Luck

Thanks for the response and help Hornet, the name reminds me of the very first car I had a 76 four door hornet

You are welcome my friend. That question was easy as I have broken many bolts too. And I am old enough to remember the Hornet. My eighth grade English teacher had one. We thought it was odd back then but I wish I had one now!

Agreed had it when I turned 16, 37 now and always thought it was an odd car then but do wish I had it now to do something interesting with it. Found the bolt online at Lowe’s the only thing they have is a 75mm one not the 74 so figured I’d just get a couple washer and put them on top of it to tighten it down.