I have been slowly working on updating and improving my 1989 Comanche Pioneer 4.0 auto 2wd. It's a farm truck, has been for a decade and doesn't get driven many miles a year, just hauling stuff from one area to another, running the trash to the dump, etc. Today when I went to move it I heard a loud noise within a few seconds of cranking so I popped the hood and noticed the belt had broken. Before I could get back to cut the engine off I heard another noise and as soon as the engine was shut off I heard the sound and observed all my coolant running out of the driver side of the engine block, below the exhaust manifold and above the oil pan gasket, in the area of the round shapes on the side of the block. I can't get the truck to the mechanic until the middle of the week due to my work schedule, but I thought I would get your thoughts on whether this is a terminal failure or possibly repairable. 4.0 engines around here (central NC) are easy to come by for a few hundred bucks, but I don't know how to put one in, and honestly am looking at whether or not to part out/salvage the truck if the repair is too expensive. Any idea what might have happened or how severe the damage could be?