How to Check a Golf Cart Battery Using a Hydrometer

In 2010, U.S. chemical manufacturers produced more than 32 million tons of sulfuric acid, according to data published by the Bureau of the Census. Everyday products that contain this corrosive chemical include lead-acid batteries, widely used to power electric golf carts and fork-lift trucks. Lead-acid batteries store energy using a reversible electrochemical reaction between lead electrodes and a dilute sulfuric acid solution, and the specific gravity of the acid, or electrolyte, in a battery determines the level of charge. Routine maintenance on golf carts includes measuring the specific gravity of the electrolyte using a hydrometer.

Things You'll Need

  • Golf cart user manual
  • Safety goggles
  • Protective gloves
  • Distilled water
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Instructions

    • 1

      Position the golf cart on level ground, ensure it is switched off and open the battery compartment. Check the user manual if you are uncertain where the batteries are located. Put on suitable personal protective equipment, including safety goggles and protective gloves.

    • 2

      Remove the screw caps or push-fit plugs from the first battery. Remove the cap from the nozzle of the hydrometer if one is fitted. Insert the nozzle into the first cell of the battery until it breaks the surface of the electrolyte.

    • 3

      Squeeze the bulb of the hydrometer gently and release it, drawing a sample of electrolyte into the hydrometer. Ensure the float inside the hydrometer is floating in the sample. If space permits, read the hydrometer while the nozzle is still in the cell, as this reduces the chance of an acid spill. Otherwise remove the hydrometer from the cell, taking care not to squeeze the bulb or spill any of the contents.

    • 4

      Check the specific gravity of the electrolyte by noting the position of the float where it breaks the surface of the acid sample inside the hydrometer. Read the scale on the float and note the number that is level with the surface of the sample. Record this number, which should be between 1.1 and 1.3.

    • 5

      Reinsert the nozzle if you removed it from the cell. Squeeze the hydrometer bulb gently to discharge the sample and remove the hydrometer from the cell. Insert the nozzle into the next cell and repeat the process, recording the specific gravity as before.

    • 6

      Continue taking samples and recording measurements until you have tested every cell on the battery. Six-volt batteries have three cells, while twelve-volt batteries have six cells. Once you have completed your tests, replace the screw caps or plugs in the battery.

    • 7

      Repeat the procedure for each battery in the cart. When you have checked every battery, rinse the hydrometer in distilled water and replace the cap. Close the battery compartment and remove your protective equipment.

    • 8

      Review the results. The electrolyte in batteries that are fully charged will have a specific gravity of around 1.28 grams per cubic centimeter. Cells that are fully discharged will give results that are close to 1.1 grams per cubic centimeter. In a good battery, the electrolyte in all the cells should have approximately the same specific gravity.