Piston engine, solid-lubricated

Figure 8.4 Some Solid Lubricant Reservoir Designs for a Small Piston Engine (Ref.209)...

There is strong evidence of extensive lubricant degradation in the piston ring zone of i/c engines under cold start conditions. This leads to a multiphase formation, with a suspended solid and two liquid phases in the first 30 minutes. This effect decreases with time as the engine temperature increases and an equilibrium single phase system is established after 60 minutes. 

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