Your fan has been shipped without oil in the motor so you will need to add it before installation. You'll find a tube of high grade SAE 10 non-detergent oil packaged in the hardware bag.
1. Remove cap if present
2. Cut the tip off the end of the tube
3. Place the tube into the oil hole and gently squeeze the tube to empty the oil into the fan's reservoir
NOTE: To avoid overflowing during filling, add a third of the oil from the tube at a time. Pause for 30 seconds between each third to allow the oil to settle in the fan. Be sure to add all of the oil in the tube to the fan.