To keep the inside working parts of your engine clean, use engine oil and fuel that have tested engine cleaning properties.

为保持引擎内部工作部件的清洁，使用经检测具有清洁引擎性能的机油和燃料。

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Slowly pour in new engine oil using a clean container or a fuel nozzle.

使用干净的容器或加油嘴缓缓倒入新的发动机机油。

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Thus the oil filter ensures that only clean oil enters the engine.

因此，机油滤清器，确保只有清洁油进入发动机。

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