Flammable gas found in the relay indicates some internal fault such as overheating or arcing, whereas air found in the relay may only indicate low oil level or a leak.

如果在继电器中发现可燃气体，这说明有内部故障，比如过热或者电弧作用；而继电器内的空气只说明油位低或者有漏油。

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This same switch will also operate on low oil level, such as a slow oil leak.

其他低油位情况发生，比如慢漏油时，浮控开关也会有动作。

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Add oil if the indicated level is too low. Make sure the oil conforms to the manufacturer's recommended viscosity.

如果油表显示的油压太低，需要加油，以确保油能符合制造商的推荐粘度。

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Investigators found that the oil level was low and there were indications that there had been a leak in the system.

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Currently, the number of days of oil demand cover is at a low of about 57, the same level we saw in 2004 and late 2007.

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The report does not rule out other possible contributors to Gulf War illness -- including low-level exposure to nerve agents and close proximity to oil well fires -- though it fails to establish any clear link.

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