An Investigation into Factors Which Affect Piston- Ring Wear under Starting Conditions

Abstract

The results of engine tests which were made, using radioactive piston rings for the measurement of engine wear, to explore the causes of start-up wear are described and discussed in this paper. The results obtained using a standard test procedure were used as data to compare the effect of applying variables immediately before and during the shut-down period. These variables included motoring the engine and changing the crankcase oil before shut-down; purging the crankcase and combustion chamber with dry nitrogen immediately the engine came to rest; and maintaining a high coolant temperature during the shut-down period. The reductions in start-up wear attributable to the variables applied have been expressed as percentages of the start-up wear incurred under the standard tests.