1. In the event, only a little hydraulic oil spilled into the water. 2. Hydraulic oil tank is equipped with power steering oil level warning device.3. The first cylinders were filled with mercury; later hydraulic oil was used. 4. Mechanical linkage also provides operator control in event of hydraulic oil pressure loss. 5. Additionally, keeping the hydraulic oil pressurized is a constant power drain. 6. The agency said airport officials believe the fire was caused by leaking hydraulic oil . 7. There are small quantities of lubricating oil, probably hydraulic oil . 8. The officials said the fire may have been caused by a leak of hydraulic oil . 9. The killer, posing as a mechanic, rigs the plane to leak hydraulic oil during the flight. 10. The candle had become contaminated with hydraulic oil , which caused the mixture to explode rather than burn.