A Volvo MD2B, 25 HP 2 cylinder. It's a hefty one at ~500lbs, not made since 1975, and the price is $175.
This is a cheap motor... for a reason, it's seized due to salt water ingress. This did NOT happen while the motor was running though I know nothing more about the circumstances other than that. I haven't contacted the seller yet as I don't want to waste their time until I'm better informed about what I might be getting into.
There is no real need for me to buy a diesel, especially a seized one, other than to have a project to work on that doesn't take up a huge amount of room, and having a working motor for a future boat project.
So how dumb an idea is this?