Well I have no idea what made this engine seize because the guy I bought it off of isn't someone I'm good friends with or anything so I haven't really talked to him about it. I guess I'll try and pull off the oil pan when I get a chance and check in there. What should I be looking for exactly? Also, if I switch this over to a KA24DE, what type of mileage is the highest a KA24DE is reliable to? I want to buy a used one and get some miles on it before I go and rebuild it.