Hi Horst. If you’re certain your coolant leak is coming from your radiator, the only proper fix would be to replace it. There are some shops that repair radiators, but I would replace it. If you want to do the repair yourself here is a video of the removal process. Remember to keep your old radiator cap, as most new radiators don’t come with a new cap. When you’re finished be sure to refill and bleed the cooling system. I hope this helps. Good luck!

https://www.youtube.com/watch?v=TWCftAXY...