Hello,I have a '49 3100 and I swapped the radiator out of a '47 as it was in better shape.I went to the parts store to get a 4 lb. cap and when they looked up the numbers it came back as a 0 pressure cap.I also noticed that Classic Parts offers a 0# and a 4# cap.Could someone please set me straight?By the way,its got a 235 babbit motor out of a '52.There doesn't appear to be a sealing lip in the fill neck to use a pressure cap. Confused, Chip
