Overview

The 2016 ISL G Near Zero (NZ) NOx natural gas engine is the first MidRange engine in North America to receive emission certifications from both the U.S. Environmental Protection Agency (EPA) and Air Resources Board (ARB) in California for meeting the 0.02 g/bhp-hr optional Near Zero NOx Emissions standards for medium-duty truck, urban bus, school bus, and refuse applications.
The game-changing Cummins Westport ISL G NZ exhaust emissions will be 90% lower than the current EPA NOx limit of 0.2 g/bhp-hr. California ARB has defined this certified Near Zero emissions level of 0.02 g/bhp-hr NOx as equivalent to a 100% battery truck using electricity from a modern combined cycle natural gas power plant. The ISL G NZ will also meet the 2017 EPA greenhouse gas emission requirements with a 9% GHG reduction from the current ISL G.
Like the industry leading ISL G engine, the ISL G Near Zero will operate on 100% natural gas which can be carried on the vehicle in either compressed (CNG) or liquefied (LNG) form. The ISL G Near Zero can also run on renewable natural gas (RNG).
The ISL G NZ will be available as a first fit engine with truck, transit, school bus, and refuse OEMs, as well as for engine replacement in existing ISL G powered natural gas vehicles.
For additional information, visit cumminswestport.com.
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.
Specifications
Advertised Horsepower |
320 hp |
239 kW |
Peak Torque |
1,000 lb-ft |
1,356 N•m |
Governed Speed |
2,200 rpm |
Clutch Engagement Torque |
550 lb-ft |
746 N•m |
Type |
4-cycle, spark-ignited, inline 6-cylinder, turbocharged, CAC |
Displacement |
540 cu. in. |
8.9 L |
Bore and Stroke |
4.49 in x 5.69 in |
114 mm x 145 mm |
Operating Cycles |
4 |
Oil System Capacity |
7.3 U.S. gal |
27.6 L |
Coolant Capacity |
13.1 U.S. qts |
12.4 L |
System Voltage |
12 V |
Net Weight w/ Std. Accessories, Dry |
1,625 lbs |
737 kg |
Aftertreatment |
Three-Way Catalyst (TWC) |
Fuel Types |
CNG / LNG / Biomethane Methane number 75 or greater |
Availability |
Click here for OEM availability |
Cummins Westport engines can accept a wide range of natural gas fuel compositions.
Use our Fuel Performance Specification Calculator to ensure compatibility.
Product Finder Specifications
Markets
|
Natural Gas
|
Certification Level
|
EPA 2013
|
Power
|
250 - 320 hp
/ 186 - 239 kW
|
Torque
|
730 - 1000 lb-ft
/ 990 - 1356 N•m
|
Ratings
Engine Model |
Advertised Horsepower (kW) @ rpm |
Peak Torque lb-ft (N•m) @ rpm |
Governed Speed |
ISL G NZ 320 |
320 (239) @ 2000 |
1000 (1356) @ 1300 |
2200 rpm |
ISL G NZ 300 |
300 (224) @ 2100 |
860 (1166) @ 1300 |
2200 rpm |
ISL G NZ 280 |
280 (209) @ 2000 |
900 (1220) @ 1300 |
2200 rpm |
ISL G NZ 260 |
260 (194) @ 2200 |
660 (895) @ 1300 |
2200 rpm |
ISL G NZ 250 |
250 (186) @ 2200 |
730 (990) @ 1300 |
2200 rpm |
Features
Factory-Built, Dedicated Natural Gas Engine – Manufactured on the same assembly line as Cummins diesels, the ISL G Near Zero, like the ISL G, shares many components and parts with Cummins L Series diesels.
- Electronic Control Module: Provides full monitoring and control of engine sensors, fuel system and ignition system, with full interface capability to Cummins INSITE and diagnostic service tools.
- Three-Way Catalyst: Simple passive device, highly effective hydrocarbon, CO and NOx control with no maintenance costs. No Diesel Particulate Filter (DPF) or Selective Catalytic Reduction (SCR) systems are required. The ISL G Near Zero catalyst includes a mid-catalyst temperature sensor connected to the ECM.
- Closed Crankcase Ventilation (CCV): The ISL G Near Zero features a chassis mounted CCV system that prevents crankcase emissions that are generated by the engine during normal operation from escaping into the atmosphere. This reduces engine related Methane emissions by 70%, by capturing crankcase emissions and redirecting them through the CCV filter where any oil is removed before sending crankcase gases back to the intake manifold to be reintroduced to the combustion chamber.
- Low installed weight: Highest power:weight ratio in its class.
- High-Energy Ignition System – Improved Ignition Control Module (ICM) provides better performance and improved spark plug and coil durability, plus self-diagnostics.
- Fuel Capability - Natural gas can be stored on the vehicle in either compressed (CNG) or liquefied (LNG) form. The ISL G can also operate on renewable natural gas or biomethane that meets fuel-quality specifications.
Maintenance
Overall, maintenance for the ISL G Near Zero is similar to that of diesel engines, but there are a few key differences:
Motor oil specifically formulated for natural gas engines is required. Do not use diesel engine oil in a natural gas engine. If diesel engine oil is used, valve torching, piston scuffing and reduction in spark-plug life will occur. For more information see the
Product Information Bulletin available on cumminswestport.com.
ISL G Near Zero Truck < 66,000 GVW
Maintenance Item |
Distance |
Hours |
Months |
Check CAC cooler, piping, and air cleaner |
7,500 mi (12,000 km) |
250 |
3 |
Oil and Filter* |
15,000 mi (24,000 km) |
500 |
6 |
Fuel Filter |
30,000 mi (48,000 km) |
1,000 |
12 |
Coolant Filter |
15,000 mi (24,000 km) |
500 |
6 |
Crankcase Ventilation Filter change |
--- |
2,000 |
12 |
Spark Plugs |
45,000 mi (72,000 km) |
1,500 |
18 |
Coolant Change |
60,000 mi (96,000 km) |
2,000 |
24 |
Valve Adjustment** |
60,000 mi (96,000 km) |
2,000 |
24 |
Air Cleaner / Element |
Follow manufacturer's published recommendations |
* Requires Natural Gas Engine Oil. **Initial valve adjustment at 1,000 hours.
|
ISL G Near Zero Urban Transit Bus and Refuse Truck
Maintenance Item^ |
Distance |
Hours |
Months |
Oil and Filter* |
7,500 mi (12,000 km) |
500 |
6 |
Fuel Filter |
15,000 mi (24,000 km) |
1,000 |
12 |
Coolant Filter |
7,500 mi (12,000 km) |
500 |
6 |
Crankcase Ventilation Filter Change |
-- |
2,000 |
12 |
Spark Plugs |
22,500 mi (36,000 km) |
1,500 |
18 |
Coolant Change |
30,000 mi (48,000 km) |
2,000 |
24 |
Valve Adjustment** |
30,000 mi (48,000 km) |
2,000 |
24 |
Air Cleaner / Element |
Follow manufacturer's published recommendations |
* Requires Natural Gas Engine Oil **Initial valve adjustment at 1,000 hours. ^Based on normal duty cycle of 15 mph average speed. Distance intervals will increase or decrease based on average speed.
|
- Default interval is the hours stated. Interval is whichever comes first – hours, miles or time.
- Refer to QuickServe® Online or Owners Manual for complete details on maintenance intervals.