Analysis of automatic transmission fluid in CNG bus engine by ferro graphic technique

Abstract

Public transportation helps to reduce road congestions, gasoline consumptions, saves money and also enhances personal opportunities. However, maintenance problem is a concern in public transportation that could cause disruption of service. In this study, this issue had been addressed in order to help prediction of wear so that the problem could be predicted before it happens. This study looks into the Compressed Natural Gas (CNG) Engine of Nadi Putra bus on the inconsistency range of mileage in changing the Automatic Transmissions Fluid (ATF). The objective of this project is to study gearbox conditions in a bus (Nadi Putra) in term of lubrication and wear. Ferrographic analysis was carried out in order to determine types of wear particles and suitable range of mileage for the bus to change the ATF by analyzing the sample of transmissions fluid taken from bus gearbox. Optical microscopy and Predict Chart were used to characterize and identify sample in where groups. It was observed that the rolling-element fatigue and cutting wear were major findings in all samples oil analysis tested.