Drill out plug, tap, use brass threaded nipple, seal with JB Weld, refill system. 85 300D, 1100 miles a week, no problems with this repair
CB

I did exactly what Chuck just posted. Same results. No leaks and it's been about 4 months since I did it.

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1983 MB 300SD Turbo Diesel

I did this attemp this repair, and the wall was was so thin and brittle it crumpled....That tells me this radiator was at least 10 years old or so, and time to replace. Hell, it might be 22 years old!!!!

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85 300CD Turbo "Das Polluter" 230K sold for $3,000

98 BMW 323is

Did this on mine almost two years ago. Still holding fine.