Now that I look at the engine pictures of the garish Willys (panel) station wagon, it occurs to me that the 134 has a road draft tube! All the HJs and post WWII Willys 4 cyls I have seen had pipes from the oil filler to the intake manifold under the carb so the crankcase was closed. That is, blowby in the crankcase was sucked back into the manifold to be burned. This pre-dated PCV valves which date from 1961 (California) and 1963 (All US).