Abstract
European legislation on hazardous exhaust emissions was stiffened in the year 2000 and will be tightened once more in 2005 Euro -IV and next step will be in 2008 -Euro V. To achieve these targets it needs optimized fuel quality. However, the effect of engine oils cannot be neglected since one of the ways to reduce exhaust emissions of diesel engines is not only to economize fuel consumption but also to reduce oil consumption. Thus engine oil has become one of important design parameters. Engine oils are expected not only to have positive effect on exhaust emissions but also to minimize frictions in an engine and provide lower fuel consumption all this resulting in lower emissions.
The paper shows that engine oils considerably contribute to diesel exhaust emissions, particularly to particulate and hydrocarbons emissions. Test of effect of some lubricant oil properties on diesel engine exhaust emission have been performed on a three cylinders DI engine (THDM 33/T-TD, 3.152 Perkins) of power/rated 40.5 kW, 2250 r.p.m. swept volume 2.5 dm 3 , turbocharged KKK 14 with intercooler.
Test results show that diesel engine emissions depend on oil properties, sulfur and polyaromatic contents above all, as well as on volatility and metal content such as calcium and zinc.