Indeed Schauberger was working with vortex action in liquids (especially in water) and was finding effects that were at the time, and are still now, unexplainable with the normal principles of physics or thermodynamics.
As far as I understand, the engine made by Clem was built around a cone with spiralling channels cut into it and when a liquid, in that particular case vegetable oil, got pressed through the channels, they caused the cone to turn. At a certain point the flow of the liquid and the turning of the cone became self-sustaining, up to the point of putting out a good and heavy (350 HP for a 200 pound engine) power output.
As I said, this is not surprising if one is familiar with the work of Schauberger. In the USA, there is one person I know of who has researched Viktor Schauberger's work in depth and who is trying to disseminate the vortex technology that grew out of Schauberger's work, through a publication called Energy Unlimited and a newsletter ("Causes"). His name is Walter Baumgartner but unfortunately I do not have contact details. To return to the Clem engine, the principle of this machine is based on the fact that vortices under certain circumstances are self-accelerating and may be used to do actual work.
One example of this in nature is the tornado, which may reach very high rotational energies without apparent input from the outside.
Schauberger used this principle before the Second World War, to run a small turbine for electric energy production that is said to have had an output of approximately nine times that a conventional turbine would have had with the same amount of water and the same altitude differential. He patented his turbine and the patent is described in a separate article of mine.
It is not known for certain what this effect is based on. From my view there are two possibilities:
1) A vortex "absorbs" ambient heat and utilizes the energy contained in it to augment its own motion. As heat is in fact molecular or atomic motion (absolute zero being the absence of any motion of this kind), a vortex could conceivably be able to direct that motion into one direction, thus ending up with
a) decreased environmental temperature and
b) increased motion.
Both factors seem to hold true for vortices.
2) The second possibility is that the vortex motion, being the most congenial motion to the aether or space background, is a means of tapping the inherent energy in space, also variously called zero-point energy, space energy or gravity field energy. A vortex, especially fast-turning and especially in dense material, may be "assisted" in its motion by a vortex forming in the space background or aether, that will eventually contribute energy to the vortex in the fluid.
These two explanations are not mutually exclusive and both mechanisms may be at work. They are at this time speculative attempts to explain properties of vortices. Although the explanations are speculative, the properties of vortices as such are not. They have been observed and measured and are shown to us daily by nature.
What Schauberger (and now Clem) have done is they have found a way to harness a phenomenon that has been given little attention by the scientific community.
The implications of this for energy production are enormous as can be readily seen reading the file CLEM1.ASC on KeelyNet.