【摘要】 通过 ９工况排放试验，分析了 Ｃ４９８Ｑ１化油器发动机排放状况及超标原因。指出化油器在高负荷区供油特性普遍偏浓是该发动机油耗偏高的重要原因。通过调整供油量特性曲线，适当延长和扩大经济混合气的供给区间，可减少ＣＯ的排放量，降低燃油消耗量，改善发动机的经济性。更多还原

【Abstract】 Based on the result of 9 - mode test cycle, the emission situation and overproof reasons of C498Q1 carburetor engine are analyzed. It is found out that the general richer fuel supply character of the carburetor in full load area is the important reason which leads to higher fuel consumption of the engine. The economic mixture gas area can be properly extended and expanded through the adjustment to the fuel supply characteristic, so that the CO emission and fuel consumption can be reduced and the engine’s economic performance improved.更多还原