Radiator Leak

'91 Explorer, V-6. I have a leak in my radiator. Top corner, pass side. The leak seems to be along the seam where the front half joins the rear half. It looks as if this radiator is made of a plastic material? Whats the best way to repair this problem? J B Weld?

Generally it's best to replace the radiator. Not too expensive for aftermarket one. This way you never have to worry if JB Weld is holding up or not. You know Murphy's Law...it'll fail at the most inconvenient time.