To determine the water percentage in DEF using a refractometer, place a drop of DEF on the prism of the refractometer, close the cover plate, and read the scale through the eyepiece; the reading will directly indicate the urea concentration (which is inversely proportional to the water percentage), with a proper DEF sample showing around 32.5% urea, meaning approximately 67.5% water content; key points are to properly calibrate the refractometer and ensure the reading is taken at a consistent temperature as this can affect the accuracy of the measurement.
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To determine the water percentage in DEF using a refractometer, place a drop of DEF on the prism of the refractometer, close the cover plate, and read the scale through the eyepiece; the reading will directly indicate the urea concentration (which is inversely proportional to the water percentage), with a proper DEF sample showing around 32.5% urea, meaning approximately 67.5% water content; key points are to properly calibrate the refractometer and ensure the reading is taken at a consistent temperature as this can affect the accuracy of the measurement.
How can you retrieve a fluid sample out of your DEF tank on a 2023 6.7L H.O.? Thanks!