The present paper describes some experiments aiming to point out the link between oil consumption and reverse blowby.
Some tests have been carried out on a motored single cylinder diesel engine. The reverse blowby gas mass flow has been evaluated by a thermodynamical model that utilizes both the measured combustion and second land pressures, and the blowby gas mass flow.
Oil consumption has been measured in real time using a CO2-tracer method, whereas the blowby has been measured by a fast response orifice meter. The first ring lifting has also been recorded.
It has been observed that, under certain engine operating conditions, both blowby and oil consumption assume quite constant levels.
On the contrary, under other operating conditions, they vary in a cyclical way. However, in both cases, a relationship between blowby, reverse blowby and oil consumption can be recognized.
The results obtained in the present research lead us to conclude that reverse blowby is one of the most significant causes of oil transport into the combustion chamber.