Years ago I purchased a replacement 1147 engine from the widow of a fellow Amphicar enthusiast. Before passing he had rebuilt the engine and had ran it briefly on a shop made test stand, and I have pulled the head and am making some checks before I install it in our early model Amphicar.
The engine appears to be a later model one as the valve cover has a tube connection for crankcase ventilation and the air cleaner has an inlet for one.
Question: On these later engines, was the draft tube / crankcase vent tube deleted and plugged? The tube on this engine appears to be pinched shut and welded together at the lowest point, where it would go into the bilge. Has anyone simply removed the draft tube and plugged the opening in the block?
Did the engines with the crankcase ventilation hose running to the air cleaner use an actual PCV valve, or was it just a simple section of hose?
That pinched off crankcase vent tube is the original correct design. Mine is the same way.
Pretty sure there has been some discussion previously which you may be able to find doing a search.
Seems a little primitive compared to what they are doing today, but for a tractor engine it passed as being acceptable.
They may have wanted to do something else when they hastily decided to use this engine for the Amphicar, but the lack of money may explain why it was simply crimped off.