Topic: Vehicle mechanics and maintenance · Nº 418 / 539
El humo que sale por el tubo de escape en un ciclomotor de 4 tiempos será...
The smoke coming out of the exhaust pipe of a 4-stroke moped will be...
- ASiempre de color muy negro.Always very black.
- BSiempre de color blanco azulado.Always bluish-white.
- CIncoloro, si el motor está en buen estado.Colourless, if the engine is in good condition.
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Correct answer
- CIncoloro, si el motor está en buen estado.Colourless, if the engine is in good condition.
The smoke coming out of the exhaust pipe of a 4-stroke moped should be colourless, since an engine in good condition should not give off visible smoke. However, black smoke may indicate a rich fuel mixture, meaning that there is too much fuel in the combustion. Bluish-white smoke, on the other hand, may be a sign that the engine is burning oil because of wear. Bear in mind that these are only possible causes; it is advisable to take the moped to a specialist workshop for a more accurate assessment.
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