I inadvertently broke off the overflow nipple from radatior, it is a clean break.
How does one repair?
I was thinking about tapping in a similar nipple that the over flow hose could connect too.

Would that work? Radatior was replaced almost 10 yrs ago and works fine.
Appreciate hearing your suggestions.
Thx
greazer2b

its worth a try. I'd drill and tap carefully then thread in a nipple with epoxy glue on the threads.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Yep;

Carefully drill and tap, use some hardening typ of sealer on the threads and GO EASY on tightening it as that plastic is brittle ! .

In Maine, I fished a 14" long thread od red RTV out of my brother's 300SDL's coolant return hose, I'm sure there's more in the radiator's tanks but he refuses as always, to let me touch it until it breaks, usually far from home ~ like four states away .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

Fyi, it isnt an overflow pipe...
It is the vapor balance port of the radiator.
Overflow would be the hose connection under the expansion tank cap on the neck that drains to a catch can on some vehicles, and on the ground on others.

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

IIRC only turbo W123s have expansion tanks. OM616s and NA OM617s have a radiator cap with overflow hose dumping out to the ground.

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Milan Brown 1979 240D, rebuilt OM617.952 turbo diesel, rebuilt 722.315 transmission (my only daily driver)

Instagram: @maximed93

From the OP's post we can readily determine the vehicle in question and the radiator configuration.

On my 944, the plastic tank is tapped and this fitting is used:

https://www.pelicanparts.com/catalog/SuperCat/1022/POR_1022_WATRAD_pg1.htm#item0

(near the bottom of the page, pn#944-106-927-00-M100)

So long as there's enough material for the thread, it should work.