Frictional analysis on engine lubricant dilution by coconut oil and soybean oil derived biodiesel

Arising world economy issues, such as depletion of world crude oil reserves, are having an impact on the transportation field and automotive manufacturers. Burning of petro-diesel contributes to the increase in greenhouse gas emissions, which traps heat within the atmosphere. To prevent this, an approach was proposed through alternative fuel production using biodiesel. However, higher blending of biodiesel in petro-diesel fuel used in compression ignition engines has been found to cause a significant dilution effect on the engine lubricants. This study presents an experimental method to investigate the frictional properties of the engine lubricant when diluted by coconut oil and soybean oil derived biodiesel. Laboratory grade biodiesel used in this study is produced using the transesterification process. Friction forces for SAE10W40 grade engine lubricant diluted at different volume fractions from 10-vol% to 90-vol% of each of the produced biodiesels are measured using the pin-on-disc friction tester. It is observed that any level of dilution of coconut oil and soybean oil biodiesel on SAE 10W40 grade engine lubricant increases frictional losses when compared with the undiluted lubricant