Cummins/Onan 6CTA8.3 — Checking Specific Gravity
Maintenance · Batteries
For the Cummins/Onan 6CTA8.3, from the Cummins/Onan operator's manual.
Applies to: Cummins/Onan 6CTA8.3, Cummins/Onan DGBB, Cummins/Onan DGBC, Cummins/Onan DGCA, Cummins/Onan DGCB, Cummins/Onan DGCG, Cummins/Onan DGFA, Cummins/Onan DGFB, Cummins/Onan DGFC, Cummins/Onan DGFS, Cummins/Onan 4B3.9 engine, Cummins/Onan 4BA3.9 engine
Procedure
- Use a battery hydrometer to check specific gravity of electrolyte in each battery cell.
- Hold hydrometer vertical and take reading.
- Correct reading by adding four gravity points (0.004) for every ten degrees electrolyte temperature is above 80°F (27°C).
- A fully charged battery will have corrected specific gravity of 1.260.
- Charge battery if reading is below 1.215.
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 if below 1.215
Full service-parts list: Cummins/Onan DGBB →, Cummins/Onan DGBC →, Cummins/Onan DGCA →, Cummins/Onan DGCB →, Cummins/Onan DGFA →, Cummins/Onan DGFB →, Cummins/Onan DGFC →
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.