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Testing Diesel Exhaust Fluid

WARNING:

Diesel Exhaust Fluid (DEF) contains urea. Do not get the substance in your eyes. In case of contact, immediately flush eyes with large amounts of water for a minimum of 15 minutes. Do not swallow. In the event the DEF is ingested, contact a physician immediately. Reference the Materials Safety Data Sheet (MSDS) for additional information.

  1. Remove the DEF fill pipe from the tank.
  2. Visually inspect the fluid for sign of contamination or debris.
  3. Collect a sample of diesel exhaust fluid from the system.
  4. Test the quality of the DEF using the DEF/UREA Refractometer 16-5025 available through Pentastar Service Equipment (PSE).
    Temperature (Constant) °C Temperature (Constant) °F Estimated Product Life
    32° Indefinite
    10° 50° 75 years
    20° 68° 11 years
    30° 86° 23 months
    35° 95° 10 months
    40° 104° 4 months
    50° 122° 1 months
    60° 140° 1 week
    1. The DEF should register approximately 32.5 percent using a refractometer.
  5. If the DEF is not within specifications then the tank needs to be drained and cleaned and refilled with a minimum of 2.5 gallons good DEF.
    NOTE:

    The use of latex gloves is mandatory to prevent false readings with the oil/hydrocarbon detection paper.

  6. To test for hydrocarbons in the DEF tank use hydroscopic test paper (PSE part number. 223-44-863). The test strip must come in contact with the DEF fluid in the tank in order to get a valid reading for hydrocarbons present in tank.
  7. Remove the oil/hydrocarbon detection paper from packing, inspect for color consistency. If color is not consistent replace strip.
  8. Disconnect the DEF fill pipe from tank and try to get a sample or remove the DEF tank. Refer to TANK, DIESEL EXHAUST FLUID, REMOVAL AND INSTALLATION .
  9. Place the detection paper directly into the DEF fluid in the tank. If the light blue paper turns dark blue, oil or hydrocarbon contamination exist.