The line of G3520J engines brings versatility, uptime, and low operating cost to your gas compression operation. They deliver the lowest engine-out emissions in the industry without sacrificing performance. Ideal applications for G3520J engines include primary gathering, central gathering, and gas processing plants.

Emissions U.S. EPA Spark Ignited Stationary NSPS emissions for 2010 U.S. EPA Spark Ignited Stationary NSPS emissions for 2010
Minimum Rating 1725 BHP 1286 bkW
Bore 6.7 in 170 mm

Technicial Specifications

Engine Specifications
Emissions U.S. EPA Spark Ignited Stationary NSPS emissions for 2010 U.S. EPA Spark Ignited Stationary NSPS emissions for 2010
Minimum Rating 1725 BHP 1286 bkW
Bore 6.7 in 170 mm
Rotation from Flywheel End Counterclockwise Counterclockwise
Stroke 7.5 in 190 mm
Combustion Lean Burn Lean Burn
Oil Change Interval 2000 hrs 2000 hrs
Capacity for Liquids
Lube Oil System - Refill 143 gal (US) 541 l
Governor and Protection
Governor and Protection Electronic (ADEM™ A3) Electronic (ADEM™ A3)

Advantages and Features

Engine Design

  • Built on G3500 LE proven reliability and durability
  • Ability to burn a wide spectrum of gaseous fuels
  • Robust diesel strength design prolongs life and lowers owning and sdfsoperating costs
  • Broad operating speed range at lower site air density (high altitude/ sdfshot ambient temperatures)
  • Higher power density improves fleet management
  • Quality engine diagnostics
  • Detonation-sensitive timing control for individual cylinderst temperatures)

Ultra Lean Burn Technology (ULB)

ULB technology uses an advanced control system, a better turbo sdfamatch, improved air and fuel mixing, and a more sophisticated sdfscombustion recipe to provide:
  • Lowest engine-out emissions
  • Highest fuel efficiency
  • Improved altitude and speed turndown
  • Stable load acceptance and load rejection


  • Meets U.S. EPA Spark Ignited Stationary NSPS emissions for 2010 and some non-attainment areas
  • Lean air/fuel mixture provides best available emissions and fuel efficiency for engines of this bore size

Advanced Digital Engine Management

ADEM A3 engine management system integrates speed control, air/fuel ratio control, and ignition/detonation controls into a complete engine management system. ADEM A3 has improved: user interface, display system, shutdown controls, and system diagnostics.

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 web-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 repair sdfsbefore-failure options
  • S•O•SSM program matches your oil and coolant samples sdfdagainst Caterpillar set standards to determine:-Internal engine component condition-Presence of unwanted fluid-Presence of combustion by-products-Site-specific oil change interval

Web Site

For all your Oil & Gas power requirements, visit www.cat.com/oilandgas

Standard Equipment

  • Air Inlet System
    • Axial Flow Air cleaner
    • Single element canister type with service indicator
  • Cooling System
    • Two-stage charge air cooling: First stage - JW + OC + 1st stage AC / Second stage - 2nd stage AC
    • Jacket water and aftercooler thermostats
  • Exhaust System
    • Water-cooled exhaust manifolds
    • Dry turbocharger housings
    • Water-cooled exhaust elbow
  • Flywheels and Flywheel Housings
    • SAE No. 21 flywheel
    • SAE No. 00 flywheel housing
    • SAE standard rotation
  • Fuel System
    • 7-40 psig gas supply
    • Electronic fuel metering valve
    • Gas pressure regulator
    • Gas shutoff valve
  • Instrumentation
    • Remote-mounted Advisor control panel
    • Product Link cellular radio
  • Lubrication System
    • Crankcase breather — top mounted
    • Oil cooler
    • Oil filter — RH
    • Oil pan — 143 gal
    • Oil sampling valve
    • Turbo oil accumulator
  • Mounting System
    • Rails
  • Power Take-Offs
    • Front housing — two-sided
    • Front lower LH accessory drive
  • General
    • Paint — Cat yellow
    • Crankshaft vibration damper and guard

Optional Equipment

  • Air Inlet System
    • Round air inlet adaptors
    • Rain shield
  • Charging System
    • CSA alternator (24V,65A)
  • Cooling System
    • Jacket water inlet flange-hose connection
  • Exhaust System
    • Flexible fittings
    • Flanges
    • Elbow
  • Fuel System
    • Fuel filter
  • Instrumentation
    • LAN adapter
    • 15',40',90',140' Product Link extension harness
    • 20',30',50',100' interconnect harness
  • Lubrication System
    • Lubricating oil
    • Oil bypass filter
    • Air prelube pump
    • Oil pan drain
  • Power Take-Offs
    • Front stub shaft
    • Crankshaft pulley
  • Starting System
    • Air pressure regulator
    • 90 psi starter
    • 150 psi starter
    • Jacket water heater
  • General
    • Special paint
    • Crankshaft vibration double damper
    • Explosion relief valves
  • EU Certification
    • EEC DOI certification