I need to decipher a VW engine code from Vanagon Wasserboxer crate engine that I've come across.

Can anyone point me to a good information source, or perhaps decipher the number for me?

Here is the number: DJS 025 100 031D

A tag on the engine also reads 2100DJ, and that is was manufactured in S.Africa

Thanks, Jim King
86 Syncro Westy