通常还有一个真空装置，用于检查真空点火提前装置的工作情况。

In addition, they usually have a vacuum device to test the operation of vacuum-advance mechanisms.

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通常还有一个真空装置，用于检查真空点火提前装置的工作情况。

In addition, they usually have a vacuum device to test the operation of vacuum-advance mechanisms.

youdao