Experimental Work on the Use of Liquefied Petroleum Gas in Single Cylinder Petrol Engine

Malaysian night markets or “Pasar Malam” in the Malaysian language are huge open markets, which convene once or twice a week in certain locations in every neighborhood. Electrical engine generators using gasoline as fuel are used as a source of electricity in these markets. The generators exhaust emission and high density of people in the market cause the air quality at the market places to deteriorate. This paper present two phases of a project aims firstly to evaluate the quality of the air in Malaysian night market and secondly to modify a single cylinder four stroke gasoline engine generator engine that widely used in the markets to use LPG as an alternative fuel. Five different locations in Kuala Lumpur were selected for this study. It was found that the gas emission level of NO₂, SO₂ and CO were above the Malaysian standard. This second part of this paper presents the results of an experimental work that was carried out at the UNIVERSITI TENAGA NASIONAL to evaluate the performance and gas emissions of night market's single cylinder four stroke and two stroke spark ignition (SI) engine generators. Engine modifications were kept to minimum in order to reduce the conversion cost. Experimental engine test showed that the engine running on LPG fuel system delivered a comparable brake power and torque in comparison with the conventional fuel. Conversion of a sample of these engines using LPG as fuel showed that the average reduction of exhaust gas emission was about 36% for CO₂, 38% for CO and 79 % for NOx in comparison to the original fuel. These figures will maintain the air quality within the Malaysian standard.