Cracked upper rad outlet

I put the hose on as far as it will go and then install 1 or 2 clamps just tight enough to hold things in place....silicone if your worried about a leak. Next safety wire the hose to the rad, wire it so that the wire pulls the hose towards the front of the car. I did this and it has held for 3 years now. TG

JB weld?

No, there is nothing that will hold the rotten pieces together, the Permatex is used so you don't have to tighten the clamps as much. Overtightening old parts is the problem. You can get a replacement rad in metal if you don't like the composite. TG