Search Results: crush on old friend

I kind of have a crush on my old high school teacher, he was only my teacher for a year and now that I'm over 18. I want to reach out, even if it's to talk in a platonic way. There were only 5 students total in the class that he taught me and honestly, he wasn't a very good teacher to me. We had lots of off topic conversations, sometimes for a very long time because other students would always be late. When we'd bump into each other outside of school hours, he'd always come to sit with me and talk and we've had many long conversations together. I think that he's someone that I'd like to be friends with even if nothing else develops. He's in his 30s and was single last I spoke to him but it's been more than a few months now.

Should I reach out at all or would this be a terrible idea. I know this sounds like a terrible idea but I'm wondering what other people think. Thank you for the opinions in advance!