Checking Hydraulic System

Before starting, check belt tension, driving pulley and tire pressure.

1. Set tool. Open shut-off valve. Then bleed air. Refer to BLEEDING HYDRAULIC SYSTEM  .
2. Run engine at idle speed or 1,000 rpm.
   NOTE: Make sure temperature of fluid in tank rises to 60 to 80°C (140 to 176°F).
   CAUTION: Warm up engine with shut-off valve fully opened. If engine is started with shut-off valve closed, fluid pressure in oil pump increases to maximum. This will raise oil temperature abnormally.
3. Check pressure with steering wheel fully turned to left and right positions with engine idling at 1,000 rpm.
   Fig 1: Checking Hydraulic System

   Courtesy of NISSAN MOTOR CO., U.S.A.
   CAUTION: Do not hold the steering wheel in a locked position for more than 15 seconds.

   Oil pump maximum standard pressure: 

   1. (QG18DE): 7,649 - 8,238 kPa (78 - 84 kg/cm ²  , 1,109 - 1,194 psi) 
   2. (QR25DE): 8,000 - 8,800 kPa (82 - 90 kg/cm ²  , 1,160 - 1,276 psi) 
   • If pressure reaches maximum operating pressure, system is OK.
   • If pressure increases above maximum operating pressure, check power steering pump flow control valve. Refer to POWER STEERING OIL PUMP  .
4. If power steering pressure is below the maximum operating pressure, slowly close shut-off valve and check pressure again.
   CAUTION: Do not close shut-off valve for more than 15 seconds.
   • If pressure increases to maximum operating pressure, gear is damaged. Refer to REMOVAL AND INSTALLATION  .
   • If pressure remains below maximum operating pressure, pump is damaged. Refer to DISASSEMBLY  .
5. After checking hydraulic system, remove tool and add fluid as necessary. Then completely bleed air out of system. Refer to BLEEDING HYDRAULIC SYSTEM  .