Thoughts on cooling a model engine with oil instead of water

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Oils, while being "dielectric", and seemingly being insulating between electro-potentials such a different metals, can manage to carry ions of water and acids and still permit corrosion, Particularly where in Engine Oil they are exposed to blow-by gases (steam/water-vapor, Co, COs, HC, NO, NOx, etc.) and heat and dynamic mixing. Or so I was told by my industrial experts.
Even Petrol and diesel can carry a tiny percentage of water seemingly in solution, only to rust a hole in the bottom of a steel tank when left for a year or 2 undisturbed.- Without dissimilar metals, or electrolytic corrosion.
Anyway, I was once told by a Professor that the corrosive properties of iron and steel can be summarised in 2 words... "Steel Rusts".
:D
K2
 
Oils, while being "dielectric", and seemingly being insulating between electro-potentials such a different metals, can manage to carry ions of water and acids and still permit corrosion, Particularly where in Engine Oil they are exposed to blow-by gases (steam/water-vapor, Co, COs, HC, NO, NOx, etc.) and heat and dynamic mixing. Or so I was told by my industrial experts.
Even Petrol and diesel can carry a tiny percentage of water seemingly in solution, only to rust a hole in the bottom of a steel tank when left for a year or 2 undisturbed.- Without dissimilar metals, or electrolytic corrosion.
Anyway, I was once told by a Professor that the corrosive properties of iron and steel can be summarised in 2 words... "Steel Rusts".
:D
K2
Technically everything is soluble in everything else at some vanishingly small concentration. But the severity of the galvanic effect inside a crankcase is minor as evidenced by the fact that aluminium pistons do not typically get destroyed by galvanic corrosion inside an iron cylinder block, even over decades of use or storage.

Anyway, the condition in the sump is quite distinct from any separate cooling system. Unless one is using the same oil for both of course.
 
...
Even Petrol and diesel can carry a tiny percentage of water seemingly in solution, only to rust a hole in the bottom of a steel tank when left for a year or 2 undisturbed.- Without dissimilar metals, or electrolytic corrosion.
Anyway, I was once told by a Professor that the corrosive properties of iron and steel can be summarised in 2 words... "Steel Rusts".
:D
K2

Biological activity should also never be overlooked in any iron based hydrocarbon storage vessel. The inevitable failure of single wall heating oil tanks is due to bacteria that use that fraction of a percent of water to eat the steel.

The same is true in hydraulic systems. I've seen clods of bacteria so dense that they were clogging a systems intake screen, causing pump cavitation.
 

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