Tough and durable, built on the industry-standard G3400 platform bring maximum uptime and low operating cost to your operation. G3406 engines meet the most demanding continuous duty gas compression applications with virtually no unscheduled downtime. Ideal applications for G3406 engines include gas lift, gas gathering, and wellhead gas compression. Cat G3406 gas engine. Ratings: 160-242 bkW (215-325 bhp) @ 1800 rpm are NSPS site compliant capable with customer-provided air-fuel ratio control and aftertreatment or available for non-regulated areas.

Engine Specifications
Minimum Rating 215 BHP
Maximum Rating 325 BHP
Emissions NSPS Site Compliant Capable
Displacement 891 in³
Compression Ratio 9.4:1
Aspiration Naturally Aspirated or Turbocharged-Aftercooled
Rotation from Flywheel End Counterclockwise
Flywheel and Flywheel Housing SAE No. 1
Flywheel Teeth 113
Weight - Dry 3000 lb
Oil Change Interval 750 hours
Ignition, Protection Altronic III
Stroke 6.5 in
Bore 5.4 in

Capacity for Liquids
Cooling System 10 gal (US)
Lube Oil System - Refill 20 gal (US)


Rich burn engine design easily meets emission requirements - 0.5% O2 rating meets U.S. EPA Spark Ignited Stationary NSPS Emissions for 2007/8 and 2010/11 with the use of aftermarket AFRC and TWC

Full Range of Attachments

Large variety of factory-installed engine attachments reduces packaging time


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

Gas Engine Rating Pro

GERP is a PC-based program designed to provide site performance capabilities for Cat® natural gas engines for the gas compression industry. GERP provides engine 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 outlets Cat factory-trained dealer technicians service every aspect of your petroleum engine Cat parts and labor warranty Preventive maintenance agreements available for repairbefore-failure options S•O•SSM program matches your oil and coolant samples against 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 production Ownership of these manufacturing processes enables Caterpillar to produce high quality, dependable products. - Cast engine blocks, heads, cylinder liners, and flywheel housings - Machine critical components - Assemble complete engine

Web Site

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

Web Site

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

Standard Equipment

Air Inlet System
  • Air cleaner — heavy-duty
  • Air cleaner rain cap
  • Service indicator
Control System
  • Governor — Woodward PSG mechanical
  • Governor locking — positive control
Cooling System
  • Thermostats and housing
  • Jacket water pump
  • Aftercooler water pump
  • Aftercooler core
Exhaust System
  • Watercooled exhaust manifolds
  • Dry exhaust elbow
Flywheel & Flywheel Housing
  • SAE No. 1 flywheel
  • SAE No. 1 flywheel housing
  • SAE standard rotation
Fuel System
  • Gas pressure regulator
  • Natural gas carburetor
Ignition System
  • Altronic III ignition system
  • Service meter
Lube System
  • Crankcase breather — top mounted
  • Oil cooler
  • Oil filter — RH
  • Auxiliary oil reservoir
  • Oil pan — full sump
  • Oil filler in valve cover, dipstick — RH
Mounting System
  • Engine supports
Protection System
  • Shutoffs
  • Paint — Cat yellow
  • Crankshaft vibration damper and drive pulleys
  • Lifting eyes

Optional Equipment

Air Inlet System
  • Precleaner
Charging System
  • Battery chargers
  • Charging alternators
  • Charging alternators f/u/w c customer supplied shutoffs
  • Ammeter gauge
  • Ammeter gauge and wiring
  • Control mounting
Control System
  • PSG Woodward governor
Cooling System
  • Radiators
  • Non-sparking blower fan
  • Blower fans for customer supplied radiators
  • Fan drives for customer supplied radiators
  • ATAAC conversion
  • Aftercooler
  • Expansion tank
  • Heat exchangers
Exhaust System
  • Flexible fittings
  • Elbow
  • Flange
  • Pipe
  • Rain cap
  • Muffler
Fuel System
  • Fuel filter
  • Natural gas valve and jet kits
Ignition System
  • CSA shielded ignition
  • Wiring harness
  • Gauges and instrument panels
Lube System
  • Auxiliary oil reservoir removal
  • Lubricating oil
Mounting System
  • Vibration isolators
Power Take-Offs
  • Auxiliary drive pulleys
  • Enclosed clutch and clutch support
  • Front stub shaft and flywheel stub shaft
Protection System
  • Gas valves
Starting System
  • Air starting motor
  • Electric air start control
  • Air pressure regulator
  • Air silencer
  • Electric starting motor— single 12- and 24-volt
  • Starting aids
  • Battery sets, cables, and rack
  • Damper guard

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