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ISL G Photo

The ISL G is the newest evolution of alternative fuel engine technology, combining all the advantages of clean-burning, natural gas engines with "no compromise" performance for shuttle bus, urban transit, school bus, vocational and urban truck/tractor pick up-and-delivery applications. The ISL G meets US EPA and CARB 2010 emission standards today.

Ratings range from 250-320 horsepower (186-239 kw). Standard features include proven wastegate turbo technology for impressive low-end torque and transient response, with an increase in fuel efficiency. These heavy-duty features give the ISL G outstanding reliability and durability.

Plus, the ISL G sets a new benchmark for lower alternative fuel vehicle life cycle costs. In high fuel use applications, the combination of lower alternative fuel costs, improved fuel economy and lower incremental maintenance costs make it possible to save valuable dollars with a natural gas powered fleet. The ISL G can also operate on biomethane -- renewable natural gas made from biogas or landfill gas that has been upgraded to pipeline and vehicle fuel quality.  Biomethane fuel is carbon dioxide (CO2) neutral.

As with all our alternative fuel engines, the ISL G comes with one of the best base warranties in the industry.  All backed by the largest customer support network in the industry.

To view and print a PDF file of our ISL G Plus brochure, click here. For additional information, visit cumminswestport.com.

 
Engine ModelAdvertised hp (kW) @ rpmPeak Torque lb-ft (N•m) @ rpmGoverned Speed @ rpm
ISL G 320320 (239) @ 20001000 (1356) @ 13002200
ISL G 300300 (224) @ 2100860 (1166) @ 13002200
ISL G 280280 (209) @ 2000900 (1220) @ 13002200
ISL G 260260 (194) @ 2200660 (895) @ 13002200
ISL G 250250 (186) @ 2200730 (990) @ 13002200

For more information, call your local Cummins distributor or Cummins Westport representative, or visit www.cumminswestport.com.

 

The ISL G engine is an excellent choice for 32,000-66,000 (14,515-29,937 kg) lb GCW/GVW short-haul applications and regional haul trucks, shuttle and school buses, urban transit buses, articulated buses, and on-/off-highway applications such as larger refuse and dump trucks. The high torque and broad power band of the ISL G provides excellent performance when matched to various manual and automatic transmissions.

Enhanced electronics provide the ability to compensate for variations in fuel quality and operating conditions, providing every alternative in fuel choices. The ISL G is capable of operating on compressed or liquid natural gas (CNG, LNG) and even landfill gas (LFG) or hydrogen blended natural gas (HCNG) that meets Cummins minimum fuel quality specifications.
Specifications.
Maximum Horsepower250-320 hp186-239 kW
Peak Torque660-1000 lb-ft895-1356 N•m
Governed Speed2100-2200 rpm
Clutch Engagement Torque550 lb-ft746 N.m
Type4 cycle, spark-ignited inline 6-cylinder, turbocharged, CAC
Engine Displacement540 cu in8.9 Liters
Bore and Stroke4.49 x 5.69 in114 x 144.5 mm
Operating Cycles4
Oil System Capacity7.3 U.S. gal27.6 Liters
Coolant Capacity13.1 U.S. qt12.4 Liters
System Voltage12 V
Net Weight w/std Accessories, Dry1,500 lb680 kg

  • Air Intake System: Charge air cooling reduces emissions by lowering intake manifold air temperatures.

  • Accessory Belt Drive System: Self-tensioning serpentine polyvee belt accessory drive system for water pump, engine-mounted fan hub and most alternators.

  • Three-Way Catalyst: Required for all models. Certified to US EPA 2010 standard and California Air Resources Board standard at 0.2 g/bhp-hr of NOx and .01 g/bhp-hr of PM. Meets EPA useful life requirement of up to 290,000 miles (464,000 km) in transit applications with no scheduled maintenance.

  • High Energy Ignition System: Provides better performance and longer service intervals, improved spark plug and coil durability, plus self-diagnostics.

  • High Efficiency Lube Cooler: Lowers oil temperatures for longer engine life.

  • Control System: Full drive-by-wire. New Electronic Control Module (ECM) provides full monitoring and control of engine sensors, fuel system and ignition system. Full interface capability to Cummins INSITE™ and QuickCheck diagnostic service tools. Control Module provides OEMs and end users with the ability to tailor performance of the engine to fit the vehicle mission.

  • Crankshaft: Eight counterweight, fully balanced, high-tensile-strength steel forging with induction-hardened fillets and journals for outstanding durability.

  • Oil Filter: The combination full-flow and bypass oil filter improves filtration while minimizing oil filter replacement and disposal costs.

  • Wastegated Turbocharger: With electronic control for precise air handling. Water-cooled bearing housing for durability.

The 8.9 liter ISL G will use stoichiometric cooled Exhaust Gas Recirculation combustion (EGR) leveraging Cummins proven EGR technology to create a high-performance natural gas engine.

The cooled EGR system takes a measured quantity of exhaust gas, passes it through a cooler to reduce temperatures before mixing it with the incoming air charge to the cylinder. The use of cooled EGR (in place of large amounts of excess air) not only lowers combustion temperatures like our current Lean Burn technology, it also allows the creation of oxygen-free exhaust, which in turn allows for the use of a Three Way Catalyst (TWC). TWCs are simple passive devices that are maintenance free and have been commonly used in passenger cars since the 1970's.

Stoichiometric cooled EGR combustion improves power density as well as fuel economy - important benefits that fleets will enjoy every day. In fact, low speed torque is improved by over 30% compared to previous engines.

 

For transit bus and shuttle bus engines - 2 years unlimited miles/kilometers with full parts and labor coverage on warrantable failures* applies. Major components are covered for 3 years/300,000 miles (482,804 km) whichever comes first.

For truck use - 2 years/250,000 miles (402,336 km) whichever comes first.

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

 
Maintenance Intervals
 Miles (Kilometers) Hours Months 
 Oil and Filter 7,500 (12,000) 500 6
 Fuel Filter 15,000 (24,000) 1,000 12
 Coolant Filter 7,500 (12,000) 500 6
 Spark Plugs 22,500 (36,000) 1,500 18
 Change Coolant 30,000 (48,000) 2,000 24
 Valve Adjustment 30,000 (48,000) 2,000 24
For complete maintenance information, please consult your Owner's Manual or Operations and Maintenance Manual.

Local service and warranty support for all Cummins Westport products are available at any authorized Cummins facility. Our customer care programs are unmatched by anyone else in the industry. Every Cummins Westport customer is supported by:

  • The largest parts and service network in the industry with over 3,500 authorized repair locations everywhere throughout the U.S. and Canada

    •  

  • Accelerated problem diagnosis at every Cummins QuickServe® location 24/7 access to Cummins

     

  • 1-800-DIESELS (1-800-343-7357)

For your nearest authorized Cummins service provider, see the Cummins service locator.

 

 



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