My 86 yer old friend has a '66 B, he started it up after it'd sat for a couple months and it began to overheat quickly. Water pump leaking. Got hoses and a pump from Moss delivered, new 160° t-stat and housing. On removal of the pump, it turned out to be one of those poxy stamped-steel impeller numbers, the pump body and bottom hose inlet had disintegrated into pieces. Flushed the radiator and ran some water through the block, thought I'd got most of it out. It sat running for a good fifteen minutes or so after reassembly, never got over 180° so thought the problem solved... got a call a few hours later and he reported it overheated on him again. Yet to go back and see if first we can flush it out more thoroughly, but I have the head gasket set here on stand-by. This could get ugly!