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Topic: Vehicle mechanics and maintenance · Nº 479 / 539

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¿Es conveniente utilizar un aceite lubricante con un índice de viscosidad tan bajo que, al calentarse el motor, se vuelva excesivamente líquido?

Is it advisable to use a lubricating oil with such a low viscosity index that it becomes too thin when the engine warms up?

  • ANo, ya que el aceite no llega a engrasar bien las piezas del motor.No, because the oil does not lubricate the engine parts properly.
  • BSí; cuanto más líquido, mejor engrasa y además arrastra los residuos depositados en el motor.Yes; the thinner it is, the better it lubricates, and it also carries away deposits in the engine.
  • CSolo si el motor se calienta en exceso, ya que engrasa mejor y ayuda a bajar su temperatura.Only if the engine overheats, because it lubricates better and helps to lower the engine temperature.
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Correct answer

  • ANo, ya que el aceite no llega a engrasar bien las piezas del motor.No, because the oil does not lubricate the engine parts properly.
Explanation

An oil that becomes too thin when hot loses its lubricating film and stops protecting the engine parts: you must use the viscosity specified by the manufacturer to make sure the engine is lubricated at any temperature.

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