Cummins/Onan — Battery Cleaning and Electrolyte Check
Maintenance · Starting batteries
From a Cummins/Onan operator's manual — check it applies to your exact model before use.
Applies to: Cummins/Onan GGHG, Cummins/Onan GGHH, Cummins/Onan V-10 WSG-1068 engine
Before you start
- Electrolyte is a dilute sulfuric acid that is harmful to the skin and eyes. Wear goggles and protective rubber gloves and apron.
- In case of contact, immediately wash skin with soap and water; flood eyes with water for at least 15 minutes and immediately call a physician.
- Ignition of explosive battery gases can cause severe personal injury or death. Do not smoke, or switch trouble light ON or OFF near battery.
Parts for this job
Part numbers from the service-parts lists for Cummins/Onan GGHG, Cummins/Onan GGHH. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Wipe batteries with a damp cloth whenever dirt appears excessive.
- If corrosion is present, remove battery cables and wash terminals with a solution of 1/4 pound baking soda in 1 quart of water.
- Be sure vent plugs are tight to keep cleaning solution out of the cells.
- Flush the outside of the battery and surrounding areas with clean water.
- Coat terminals with petroleum jelly or non-conductive grease to retard corrosion.
- Check electrolyte specific gravity with a hydrometer; correct reading by adding 0.004 for every 10°F above 80°F (27°C).
- Check electrolyte level at least every 200 hours; fill cells to bottom of filler neck with distilled water.
Tools required
- Battery hydrometer Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Fully charged corrected specific gravity 1.260
- Charge battery if reading is below 1.215
- Check electrolyte level at least every 200 hours of operation
Full service-parts list: Cummins/Onan GGHG →, Cummins/Onan GGHH →
Source: Cummins/Onan operator's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.