Diesels never were carb'd - there's no venturi effect possible without vacuum. There's no spark. It's just totally different.

They always have direct injection into the cylinder as far as I know. Maybe in the early 1900's they did manifold injection but I don't think so.

It's just a total different concept.

How the metering is done (IE How much fuel to meet load) though may have been similar, I am not sure. I 'asked a friend' on this one, since I am really unfamiliar with diesels in general.