Cummins/Onan DL3 — Battery Checkout
Maintenance · Battery BT1
For the Cummins/Onan DL3, from the Cummins/Onan service manual.
Applies to: Cummins/Onan L Series Diesel engine
Before you start
- Ignition of explosive battery gases can cause severe personal injury; no flame, spark, cigarette or other ignition source near the battery.
Procedure
- Check charge condition of battery with a hydrometer.
- Electrolyte specific gravity should be about 1.260 for a fully charged battery at 80°F (27°C).
- If not, add distilled water to keep electrolyte at proper level and recharge battery.
- If battery will not recharge, replace it.
- If battery state-of-charge is not maintained, charge rate may be too low; see Checkout [C].
Tools required
- Hydrometer Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Electrolyte specific gravity about 1.260 at 80°F (27°C)
Source: Cummins/Onan service 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.