Get both manuals, they're cheap enough
I have both Yanmar manuals and they each have good and bad points. The procedures for removal of valve covers is not very detailed in the non-Yanmar manual. The theory of operation is not covered at all in the Yanmar manual. I have found that using both, gives a complete coverage of every subsystem.Get the Yanmar manual from Mack Boring or any authorized parts dealer. Highly recommend the Engine City Tech classes.