Tough and durable, built on the industry-standard G3400 platform bring maximum uptime and low operating cost to your operation. G3412C Low Emissions (LE) engines meet the most demanding continuous duty gas compression applications with virtually no unscheduled downtime.Ideal applications for G3412C (LE) engines include gas lift, gas gathering, and wellhead gas compression. Cat G3412C (LE) gas engine. Ratings: 475 bkW (637 bhp) @ 1800 rpm are NSPS site compliant capable with customer-provided aftertreatment.

Engine Specifications
Minimum Rating 637 BHP
Maximum Rating 637 BHP
Emissions NSPS Site Compliant Capable
Displacement 1649 in³
Compression Ratio 8.5:1
Aspiration Turbocharged-Aftercooled
Rotation from Flywheel End Counterclockwise
Flywheel and Flywheel Housing SAE No. 0
Flywheel Teeth 136
Weight - Dry 4720 lb
Oil Change Interval 750 hours
Ignition, Protection Cat EIS
Stroke 6 in
Bore 5.4 in

Capacity for Liquids
Cooling System 14.5 gal (US)
Lube Oil System - Refill 45 gal (US)

Engine Design

- Proven reliability and durability- Ability to burn a wide spectrum of gaseous fuels- Robust diesel strength design prolongs life and lowersowning and operating costs- Broad operating speed range


- Meets U.S. EPA Spark Ignited Stationary NSPSEmissions for 2007/8- 2.0 g/bhp-hr NOx emission versions available- Larger turbocharger and aftercooler provide leanair/fuel mixture, low emissions, and excellent fuelconsumption

Lean Burn Engine Technology

Lean-burn engines operate with large amounts of excessair. The excess air absorbs heat during combustionreducing the combustion temperature and pressure,greatly reducing levels of NOx. Lean-burn design alsoprovides longer component life and excellent fuelconsumption.

Caterpillar Electronic Ignition System (EIS)

Detonation sensitive timing protects the engine againstdetonation damage. Higher voltage and longer sparkduration mean easier starts, fewer misfires, andsmoother operation. Diagnostic codes help pinpointcylinder and component of interest. Spark plugmaintenance codes identify spark plug condition

Ease of Operation

-    Deep sump oil pan has a larger capacity for normal750-hour oil change intervals- High-strength pan and rails for excellent mounting andstability- Side covers on block allow for inspection of internalcomponents

Full Range of Attachments

Large variety of factory-installed engine attachmentsreduces packaging time


Every engine is full-load tested to ensure proper engineperformance.

Gas Engine Rating Pro

GERP is a PC-based program designed to provide siteperformance capabilities for Cat®natural gas enginesfor the gas compression industry. GERP providesengine data for your site's altitude, ambient temperature,fuel, engine coolant heat rejection, performance data,installation drawings, spec sheets, and pump curves.

Product Support Offered Through Global Cat Dealer

More than 2,200 dealer outletsCat factory-trained dealer technicians service everyaspect of your petroleum engineCat parts and labor warrantyPreventive maintenance agreements available for repairbefore-failure optionsS•O•SSM program matches your oil and coolant samplesagainst Caterpillar set standards to determine:- Internal engine component condition- Presence of unwanted fluids- Presence of combustion by-products- Site-specific oil change interval

Over 80 Years of Engine Manufacturing Experience

Over 60 years of natural gas engine productionOwnership of these manufacturing processes enablesCaterpillar to produce high quality, dependable products.- Cast engine blocks, heads, cylinder liners, and flywheelhousings- Machine critical components- Assemble complete engine

Web Site

For all your petroleum power requirements, visit www.catoilandgasinfo.com

Standard Equipment

Air Inlet System
  • Air cleaner — single element with service indicator
Control System
  • Electronic governor
  • Air/fuel ratio control on 1.0 g/bhp-hr NOx engines
Cooling System
  • Thermostats and housing
  • Jacket water pump
  • Aftercooler water pump
  • Aftercooler core
Exhaust System
  • Watercooled exhaust manifolds
  • Dry exhaust elbow
Flywheels & Flywheel Housings
  • SAE No. 0 flywheel
  • SAE No. 1 flywheel housing
  • SAE standard rotation
Fuel System
  • Gas pressure regulator (1.5 to 5 psi gas supply required)
  • Natural gas carburetor
Ignition System
  • Cat Electronic Ignition System (EIS) with detonationsensitive timing
  • Service meter
Lube System
  • Crankcase breather — top mounted
  • Oil cooler
  • Oil filter — RH
  • Oil pan — deep sump
  • Oil filler — RH in valve cover and RH dipstick
Mounting System
  • Engine supports
Protection System
  • Detonation sensitive timing control
  • Shutoff
  • Paint — Cat yellow
  • Crankshaft vibration damper and pulleys
  • Lifting eyes

Optional Equipment

Air Inlet System
  • Air cleaner — two-stage
  • Air inlet adapter
  • Precleaner
  • Air cleaner rain cap
Charging System
  • Battery chargers
  • Charging alternators
  • Ammeter gauge
  • Ammeter gauge and wiring
  • Control mounting
Cooling System
  • Radiators
  • Blower fan and fan drives for customer suppliedradiators
  • Expansion tank
  • Heat exchangers
Exhaust System
  • Flexible fittings
  • Elbows
  • Flanges
  • Rain caps
  • Mufflers
Fuel System
  • Dual gas regulator
  • Carburetor kits
  • Fuel filter
Ignition System
  • CSA ignition
  • Ignition ground wiring harness
  • Power supply
  • Alarm module
  • Gauges and instrument panels
Mounting System
  • Vibration isolators
Power Take-Offs
  • Auxiliary drive pulleys
  • Enclosed clutch and clutch support
  • Front stub shaft
  • Flywheel stub shaft
  • Pulley removal
Protection System
  • Gas valves
  • Status control box interconnect wiring harness
Starting System
  • Air starting motor — electric air start control
  • Air pressure regulator
  • Air silencer
  • Electric starting motors — single 24-volt
  • Starting aids
  • Battery sets
  • Special paint

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