Naturally Better. Cummins Westport ISL G Natural Gas Engine.

There are over 40,000 Cummins Westport natural gas engine-equipped vehicles performing cleanly and reliably today. Interest in natural gas engines is steadily growing throughout North America, with Cummins Westport natural gas engines widely recognized for their technological leadership in urban transit fleets. The ISL G combines all the advantages of clean burning natural gas with no compromise in power or torque. 

The ISL G uses Stoichiometric cooled Exhaust Gas Recirculation (SEGR) combustion to create the optimal combination of power, torque and low emissions levels. Stoichiometric combustion is the ideal ratio at which fuel and oxygen are both completely consumed.

The oxygen free exhaust stream enables the use of our proprietary Three-Way Catalyst (TWC). This completely passive device never needs additional fluids, regeneration or cleaning, and takes the place of a conventional muffler. Fuel for the Cummins Westport ISL G can be stored on the vehicle as compressed natural gas (CNG) or liquefied natural gas (LNG). The ISL G can also run on renewable natural gas (RNG) made from biogas or landfill gas that has been upgraded for vehicle fuel quality.

The ISL G shares 80 percent of its heavy duty components with its diesel counterpart, the Cummins ISL9. This increases durability and reliability while reducing the overall ownership cost. The troubleshooting capabilities (using Cummins standard software and diagnostic tools) are also shared.

Considering a Cummins engine purchase? For more information including pricing and additional technical information, please contact your Cummins representative. If you need help finding a representative, the Cummins Sales and Service Locator tool can help. 

Features & Benefits

Proven Wastegate Turbo From Cummins Turbo Technologies
A simple, reliable design from the world leader in turbocharging technology.

Three-Way Catalyst (TWC) From Cummins Emission Solutions
TWCs are passive devices packaged as part of the muffler, and are maintenance-free. The ISL G des not require active aftertreatment such as a particulate filter or Selective Catalytic Reduction (SCR).

Fully Skirted ISL Diesel Engine Block
The high-strength, rebuildable design adds durability. Shares 80 percent of major engine components with the ISL9 diesel.

Stoichiometric Cooled EGR
The ideal air/fuel ratio for complete combustion means zero oxygen in the exhaust, which allows use of the passive Three-Way Catalyst.

High-Capacity Electronic Control Module (ECM)
Provides full monitoring and control of engine sensors, the fuel system and the ignition system. Compatible with Cummins software and other diagnostic service tools.

High Energy Ignition System
Provides better performance, longer service intervals and improved spark plug and coil durability, plus self-diagnostics. A coil-on-plug ignition system eliminates the need for spark plug wires.

QuickServe® Online.
QuickServe Online sorts through 11 million Cummins engines and a million documents in seconds to find accurate, up-to-the-minute parts and service information about a customer’s engine. Every fact is instantly available, from part numbers, diagrams and supercessions to service bulletins and troubleshooting manuals, operation and maintenance manuals, literature, tools, catalogs and more. See quickserve.cummins.com for access information.

Genuine Cummins New And ReCon® Parts.
We stock parts for 100,000 individual part numbers at our Memphis Distribution Center, including both new (Genuine Cummins) and remanufactured (ReCon) parts. Our centralized distribution network assures next-day delivery almost everywhere in North America on parts orders received by midnight EST. Genuine Cummins Parts are of the highest quality and backed by the best parts warranty in the industry. And we are so confident in the reliability of Genuine Cummins ReCon parts that every one comes with a full Cummins warranty.

Training Every Technician.
Make sure your technicians have the training on all the latest technology. Cummins distributors offer local training using the same diagnostic procedures and repair techniques that are taught by our factory personnel.

Every Confidence.
All Cummins and Cummins Westport transit engines come with a standard 2-year/unlimited-mileage warranty with full parts and labor on warrantable failures.* This includes travel or towing when a bus is disabled or when further operation would cause additional damage. Major components are covered up to 3 years or 300,000 miles (482,804 km), whichever occurs first, on Cummins ISL9 and ISL G urban transit bus engines.

* Warrantable failures are those due to defects in materials or Cummins workmanship.

Better Extended Coverage.
For additional peace of mind, Cummins and Cummins Westport offer a variety of extended coverage plans to meet every transit operation’s needs. Check with your local Cummins distributor for details.

Better Service. Everywhere.
Cummins-powered urban transit buses are backed by the largest and most capable parts, service and support network in North America, with nearly 3,500 locations. Our authorized technicians are fully trained on all our engines, and have the necessary equipment and Genuine Cummins Parts to handle any type of service issue. Call 1-800-DIESELS™ (1-800-343-7357) for information and service locations.