360 crankshaft end play

I pulled a 22 ft searey boat with a 318 .73 van..it wiped out the TBearing and the way I found out was when it was cold on first startup it would knock..loud..it was the harmonic balancer pounding on the front of the motor..it would come and go till the motor warmed..thru it away and put in a 360..the block with the big tbearing..all at 60 thou and a 5500 min load..j