I have seen one engine diagram that used a non-geard pump. It used 2 figure 8
shaped lobes that were mounted perpendicular to each other. I don't remeber
what engine it was but I seem to recall it being a straight 8 for some reason.
Its anyone's guess about who made it. The book was printed sometime in the
1940's. Other pumps of this style were known for large volumes but at low
pressure. Who knows, low pressure oiling was common on early engines.

Dennis
ASE Master Auto Tech and Marine Engineer in training--but JAX believes I should
go back to study hall)

I have never seen any oil pump on any engine going back to designs around
since
the early 20th century that were not geared, except for the B&S engine which
uses a scoop on the bottom of the connecting rod cap to supply pressure oil.

genee/rickie claim non-geared oil pumps on engines are common. Anyone know
which engine designs used oil pumps that are not geared?