Actually, there are more manuals for the 237 and one does not have the larger dial for the pressure regulating dial. I can't find a free one on the web but a paid version at
https://manualsoncd.com/product/sing...uction-manual/. I got mine from Yahoo Groups. Here is another manual that does not have the treadle and the bobbin is not quite as large, but still larger than really is.
https://www.manualslib.com/manual/29...?page=1#manual
I think this is probably the one that you got from ismacs
https://www.manualslib.com/manual/86...?page=1#manual
Janey - Neat people never make the exciting discoveries I do.
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