There is an older model Farmall C which didn't come in that large an engine, we are talking old, old.
The one you are referring to must be the newer make, not the same as the old one at all. As Stublinhorse says it, new model, is made by CNH who also makes the New Holland.
The new Case IH 50C has the Shibaura engine, it appears. I know that Shibaura is a great Japanese made engine that they have been putting in a lot of Ford/New Holland and Case IH tractors for many years. We have a Massey Ferguson 1750M with a Shibaura engine in it and it is a great runner. I also had a little SCUT Case IH DX24e with the Shibaura engine in it and it was a great little tractor. That engine starts almost as easy as a Yanmar in the winter, almost. Years ago, I also had a old Ford 1215 (Made in the 90's for reference how long they have been using Shibaura) Subcompact with the engine in it, no issues with that engine either.
My experience with Shibaura is, it is in the same conversation of quality as the Yanmar/Kubota/Iseki. Among the best for small tractors. This is my opinion, no proof of this, just based on my experience with them.
I do not know about the DEF on the tractor you are looking into. None of mine had/have DEF. That would be what I would do my research on. Ask the dealers, google any known DEF issues with that model etc.
If you don't read of a lot of significant DEF issues, I would buy it.
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