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Maintenance tip: heat finds H2O

Is water in your hydraulic fluid? Here's a quick and simple way to find out.

You may need to learn whether water is present in a hydraulic reservoir, contaminating the fluid. This problem normally occurs when the reservoir ingests humid ambient air as the fluid level drops. Later, when the system cools, water can condense on the inside of the reservoir’s walls. In other situations, sanitary requirements may dictate an equipment washdown. In either case, a water-contamination check should follow.

Two very simple tools — a spoon and a cigarette lighter — can accomplish this test. Fill the spoon with fluid from the reservoir, then heat it over the lighter. In about 30 seconds if water is present, you’ll see bubbles forming at the bottom of the spoon and rising to the fluid surface. If there’s no water, no bubbles will appear.

Ronald R. Gould, PE, is Vice President - Engineering at Advance Lifts Inc., St. Charles, Ill.