||The article presents an analysis of phenomena of selected elements of piston internal combustion engines cooperating with the combustion chamber and issues related to tribological aspects. It shows an attempt to assess the state of the tribological nodes: the valve stem – valve guide and valve head – valve seat in random natural conditions.
Passive and passive-active experiments were conducted in the conditions of the operation of sea ships. The effects of complex and changeable inputs were examined on the value of the normal and pathological wear in the operation of medium-speed engines. Images of wear and damaged items of tribological nodes were studied.
Analysis was conducted of digital images of real objects and using an optical microscope and measurements of macro- and micro-geometry. An identification of basic processes of wear was taken.