Cummins 4BTA3.9-G2 vs Isuzu 4JJ1X
The Cummins 4BTA3.9-G2 and Isuzu 4JJ1X are both diesel generator engines in a similar power class. Both are rated at roughly 71 kVA. Displacement is 3.9 L versus 2.999 L. The table below compares their full specifications side by side.
| Specification | Cummins 4BTA3.9-G2 | Isuzu 4JJ1X |
|---|---|---|
| Headline rating | 70 kVA | 71 kVA |
| Standby (50 Hz) | 56 kWe | 56.4 kWe |
| Prime (50 Hz) | 45 kWe | 51.3 kWe |
| Standby (60 Hz) | 64 kWe | 70.3 kWe |
| Prime (60 Hz) | 51 kWe | 63.9 kWe |
| Displacement | 3.9 L | 2.999 L |
| Configuration | L4 | L4 |
| Cylinders | 4 | 4 |
| Rated speed | 1,500 / 1,800 RPM | 1,500 / 1,800 RPM |
| Fuel | Diesel | Diesel |
| Cooling | Liquid-Cooled | Liquid-Cooled |
| Emissions | Unregulated | U.S. EPA Final Tier 4 |
| Dry weight | — | — |
| Origin | China | Japan |