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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> External Pages >> Different car >> Section 843 (Engine Cooling System) >> Radiator >> Checking Radiator Cap
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Checking Radiator Cap

WARNING: This page is about a different car, the 2003 Nissan Murano. However, it is still accessible from the selected car via links, so may be relevant.
  1. Pull the negative-pressure valve to open it and check that it closes completely when released.
    Fig 1: Checking Negative-Pressure Valve
    G01269824Courtesy of NISSAN MOTOR CO., U.S.A.
    • Check that there is no dirt or damage on the valve seat of the radiator cap negative-pressure valve.
    • Check that there are no unusualness in the opening and closing conditions of the negative-pressure valve.
  2. Check radiator cap relief pressure.
    Fig 2: Checking Radiator Cap Relief Pressure
    G01269825Courtesy of NISSAN MOTOR CO., U.S.A.
    1. Standard:
    2. 78 - 98 kPa (0.8 - 1.0 kg/cm 2  , 11 - 14 psi) 
    3. Limit:
    4. 59 kPa (0.6 kg/cm 2  , 9 psi) 
    • When connecting the radiator cap to the tester, apply engine coolant to the cap seal surface.
    • Replace the radiator cap if there is an unusualness in the negative-pressure valve, or if the open-valve pressure is outside of the limit.