You have a 1946 Firestone model 460, made by Scott-Atwater. Your serial number is 38671. I have the same motor. Your impeller looks okay to me. Should pump fine if the passages are clear. These were known for bad head gaskets, which may be why you’re seeing water near the head bolt. Scott went to a six bolt head in 1947, likely to alleviate that problem. They also converted to the wobble rotor pump in ’47.
John Van
