Rad Caps??

I've got the same issue. After a drive and warm up I get a top seam leak and a thin line runs down the top seam. I too have a new cap (16lb) and still get it. My rad is a cheapo parts store 22" replacement that I have no idea how old it is. I'm going to try a bottle of leak stop I got from Hughes now that my engine's back together and I'll let you know if that works. I was hoping to avoid the JB Weld route myself!

I too am biding my time and living with it until I can get an alluminum rad and electric fan package. It's just annoying to pop the hood and know you need to wipe it down at a cruise night or show!