Oil pressure seemed to drop , but I don't know whether that was a consequence of the oil pump not spinning fast enough or whether it was a factor in why it was dying. When I hold the starter for ten seconds, it does have a bit of pressure on the gauge (10lbs maybe?) but it doesn't build to like 40-50lbs. But that doesn't mean much to me - when we started the motor for the first time, it didn't show oil pressure building, but when it's on, it's had 75lbs cold and 40-50lbs hot like clockwork.

The engine didn't get that warm overall, and never overheated before this happened.

I am going to check for spark and change the oil tonight.