新汽车未经磨合运转不要开得太快。

Don't drive your new car too fast until you've run it in.

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新车在磨合期期间常常满载运转，则归于负荷过重，会致使发动机及变速箱的负荷增大。

The new car in the running in period is often full load operation, the load is too heavy, will cause the engine and gearbox load increase.

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铝活塞的表面常常镀锡，以便在发动机开始运转阶段能进行适当的磨合。

Often, aluminum pistons are tin-plated to allow proper break-in when the engine is started.

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