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Black Pepper in your Radiator?

This happened in the early 1980’s while returning from Morehead Beach, NC with cousins and friends. The van’s radiator overheated and was leaking. We were trying to make it back to LaGrange by stopping, allowing the car to cool down, adding water.

We encountered an older man who warned that it sounded strange, but we should buy a can of black pepper and pour it into the radiator, which would seal the leak to get us home. And we did. And it didn’t work. We laughed the rest of the way home and had an entertaining story to tell relatives.

Has anyone ever heard of this? I have no idea what kind of van my cousin was driving, but it was not a newer model.

I am old enough to have worked on cars from the 1930s and earlier. I never heard of black pepper in a copper radiator, but some, when they had a small leak, would put uncooked oatmeal into the radiator, it would travel to the leak and clog it for a period of time. A number of things need to be kept in mind with the old cars: Radiators were copper, not plastic, people ran water in the radiators or, in the Winter, one season glycol (or alcohol). Some water pumps had externat lubricating systems and didn’t need radiator additives, engine block cooling passages were much simpler, as was the heater core. I would not recommend oatmeal in any car past the 1940s. Oldmotorist

The use of black pepper to seal small leaks is very common, in emergencys be they pratical or financial. I am suprised more people have not commented. Have not used the process myself.You can’t expect black pepper to fix a hole caused by a deer antler though (unless it is a reall tiny deer I guess).

I recommended it to a guy on Fri. for a leaking radiator, I may have first hand knowledge soon.

As oldschool noted, its common and it works on small leaks.

I Have used it a couple of times,it got me home without killing the engine,it does work .