Refractometer and practices

The main components of our current coolants are a base fluid, additives and water (in case of a ready mix). In case of Havoline^© XLI it is water and additives.

Before measuring the freezing point or refractive index of a coolant, make sure you know what kind of coolant you’re dealing with. Based on this information you choose either a refractometer with MEG/PG scale or a brix meter.

Steps to follow:

• Let cool down the engine to room temperature and then take a sample;

• Calibrate the refractometer/brix meter with water. If the level is not zero, you can adjust with the screw;

• Put some sample on the surface, one drop is sufficient, cover with the top plate;

• Read out;

• Use the appropriate calibration curves.

What if the measurement doesn’t meet the expectations?

• Verify the temperature;

• Look if there are no air bubbles between the measuring surface and the cover;

• If you have no read-out, this means the sample is too concentrated, corrective action required;

• If your result is too low, corrective action is required;

• Contaminations can also give a wrong read-out;

• If you’re not sure of the base fluid either MEG or PG, read out the MEG scale;

• The refractometer is custom made for MEG and PG. Other base fluids e.g. glycerol gives wrong results.