Cummins/Onan — Cleaning the Battery
Maintenance · Starting battery
From a Cummins/Onan operator's manual covering: MDL3, MDL4, MDL6. Check it applies to your exact model before use.
Applies to: Cummins/Onan MDL3, Cummins/Onan MDL4, Cummins/Onan MDL6, Cummins/Onan 3A1.7 engine, Cummins/Onan 4A2.3 engine, Cummins/Onan 6A3.4 engine
Before you start
- Battery electrolyte can cause severe eye damage and burns to the skin; wear goggles, rubber gloves and a protective apron.
- Ignition of explosive battery gases can cause severe personal injury; do not smoke.
Procedure
- Wipe battery clean with a damp cloth whenever dirty.
- Remove battery cables (negative cable first) if corrosion is present.
- Wash terminals with ammonia solution or 1/4 pound (about 100 grams) baking soda in 1 quart (about 1 liter) water.
- Remove battery from vessel for cleaning and keep vent plugs tight.
- Flush outside of battery and surrounding areas with clean water.
- Coat terminals with non-conductive grease or petroleum jelly.
Specs & values
- Fully charged corrected specific gravity 1.260; charge if below 1.215
Full service-parts list: Cummins/Onan MDL3 →, Cummins/Onan MDL4 →, Cummins/Onan MDL6 →
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.