Examples from the Web for crankcase
With the crankcase, they did not go all the way to the modern two-piece form but instead retained the one-piece construction.
This type of fastening actually strengthened the crankcase in contrast to the usual method.The First Airplane Diesel Engine: Packard Model DR-980 of 1928|Robert B. Meyer
I just put a connecting-rod through my crankcase, growled the man.The Flying Reporter|Lewis E. (Lewis Edwin) Theiss
Although the crankcase had shown itself to be structurally weak, this could have been cared for by proper strengthening.
Magnalium takes the place of aluminum in the crankcase, because it is not only lighter but stronger and can be cast very thin.Flying Machines|W.J. Jackman and Thos. H. Russell