An Increase of Engine Oil Consumption at High Temperature of Piston and Cylinder

Under high thermal load operation, engine oil consumption was monitored using the hydrogen fuel method. Burning was detected in the piston top-land clearance, and this may be a key to understanding the carbon adhesion mechanism on the piston top-land. The following results were obtained in this study:

1. 1.
   Oil consumption is greatly affected by the evaporation of oil at temperatures higher than 160°C.
2. 2.
   Burning is found in top-land clearances of hydrogen, gasoline, and large clearance diesel engines. However, only weak burning could be detected in diesel engines with tight-fitting crowns.