The engine valvetrain system operating under conditions of insufficient oil lubrication, caused by incorrect installation of the gasket between the block and the head, was tested. The aim of the analysis was to determine the wear intensity and resistance to motion in camshaft bearings. A model was developed that includes a camshaft, bearings, tappet-valve-spring subassemblies and a part of the lubrication system. It was used to determine the bearing loads and the amount of oil supplied. The volumetric wear of the camshaft journals and bearing covers was measured. For the estimated engine run, the wear rate and resistance to motion were compared for the cases of the engine with correct and incorrect lubrication.