Manufacturer: Caterpillar
Engine Model: G3304
Fuel Type: Natural Gas (also compatible with field gas / LP with setup)
Cycle: 4-stroke
Aspiration: Naturally Aspirated (some variants turbocharged, but G3304 is typically NA)
Application: Generator sets, compression, industrial power
Configuration: Inline 4-cylinder
Displacement: 7.0 L (428 cu in)
Bore x Stroke: 4.75 in × 6.00 in
Compression Ratio: ~9.5:1 (varies by setup)
Continuous Power: 85–100 HP
Rated Speed: 1800 RPM (60 Hz genset use)
Torque: ~300–330 lb-ft
(Exact rating depends on gas quality, altitude, and ignition setup.)
Ignition System: Magneto or electronic ignition (application dependent)
Starting System: 24 VDC (most industrial packages)
Cooling: Jacket-water cooled
Oil Capacity: ~4–5 gallons
Oil Pressure (hot): 35–55 psi
Recommended Oil: SAE 30 or SAE 40 (stationary gas engine oil)