NANO

230 ENGINE 273 MPFI SYSTEM COMPONENTS CATALYTIC CONVERTER Catalytic converter is a device that uses a catalyst to convert three harmful compounds in exhaust gases into harmless compounds. The three harmful compounds are: (a) Hydrocarbons (HC) (in the form of unburned gasoline) (b) Carbon monoxide (CO) (formed by the combustion of gasoline) (c) Nitrogen oxides (NOx) (created when the heat in the engine forces nitrogen in the air to combine with oxygen) In a catalytic converter, the catalyst (in the form of platinum and palladium) is coated onto a ceramic honeycomb. The catalyst helps to convert carbon monoxide into carbon dioxide. It converts the hydrocarbons into carbon dioxide and water. It also converts the nitrogen oxides back into nitrogen and oxygen. A catalyst is a substance that causes or accelerates a chemical reaction without itself being affected. Catalysts participate in the reactions, but are neither reactants nor products of the reaction they catalyze. In the catalytic converter, there are two different types of catalyst at work, a reduction catalyst and an oxidation catalyst. The reduction catalyst is the first stage of the catalytic converter. It uses platinum and rhodium to help in reducing NOx emissions. The oxidation catalyst is the second stage of the catalyt ic converter. It reduces the unburned hydrocarbons and carbon monoxide by burning (oxidizing) them over a platinum and palladium catalyst. SILENCER ASSEMBLY Inside a silencer, there are set of tubes which finely tuned and designed to reflect the sound waves produced by the engine in such a way that they partially cancel themselves out. If there is a hole in the silencer then the sound waves are no longer forced through the tubes and escape outside - increasing the noise level.