Automatic Lubricator

Some vehicles that require lubrication come equipped with an automatic lubricator. This is a small device with a meter on the right side, representing oil level in the drivetrain bearings that it lubricates.

When the vehicle is in motion, it will spend that oil. However, the automatic lubricator automatically replenishes it from the onboard storage, shown on the left meter.

If the vehicle has been parked and the bearings have run dry, the lubricator must be manually primed by turning a crank on it, until full, before the vehicle can be set in motion again.