With the correct oil, friction losses in an engine are reduced to a minimum. This is done by taking into consideration circumstances as engine usage, ambient temperature, time of year and climate, location and engine design. The engine manufacturer usually recommends a certain type of oil to use taking these circumstances into account.
Engine oil contains additives known as friction modifiers/reducers and anti wear additives which are soluble and are used in the lubrication industry for many years now.
You as an experimental aircraft builder are probably using them without the full appreciation for the properties of these additives. Application of wheel bearing grease and of course engine oil is usually done without much thought. On this page we touch on a complicated subject explaining why and how these additives are used.
Although used in the automotive industries, aviation can use these products too with the same good results!
Excerpt from the document:
Molykote Anti-Friction Coatings are bonded, dry-film lubricants that provide superior lubrication in harsh operating conditions and environmental extremes. They are economical to apply, long lasting and valued in uses where other lubricants fail. Compared to typical lubricating pastes and greases, Molykote Anti-Friction Coatings have a number of advantages.
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