Evaluation of Test Strips for On-Site Monitoring of Coolants in Heavy-Duty Diesel Engines

A test strip containing three pads for measuring the freezepoint protection, molybdate and nitrite levels in heavy-duty diesel engine cooling systems has been developed for commercial use. The test strip requires no pretreatment or dilution of the sample, other than to allow it to cool to 130 degrees F or lower, and gives results for all three tests within two minutes. The test results are sufficiently accurate, and the strips are stable over extended periods of time, provided the container is kept tightly closed and away from direct sunlight and prolonged elevated temperatures when not in use.

The freezepoint test offers an inexpensive alternative to refractometers. Since it can be used with either ethylene or propylene glycol coolants, it is recommended over the use of hydrometers. The molybdate and nitrite test pads give accurate readings for supplemental cooling additive (SCA) levels in coolants, helping to maintain the proper level to prevent cavitation corrosion from undertreatment, or water pump seal leakage and failure from overtreatment and high dissolved solids levels.