Reduce Fleet Downtime: Understanding CNG Ignition Systems
By Kasia McBride, Marketing Manager, NGVi Natural gas engines differ significantly from their diesel counterparts, and technicians who maintain them must have a full understanding of their operation and specific diagnostic parameters. Perhaps the most prominent difference these technicians must deal with is the fact that natural gas fuel ignites via spark ignition–not compression ignition, […]
How to Minimize Costly ($42,000?) Oil Carryover Problems in Heavy-Duty Natural Gas Engines
By Annalloyd Thomason, Vice President/General Manager, NGVi They are the most common performance complaints for heavy-duty natural gas vehicles: Hard to start Idles rough Hesitates under acceleration Low power Sometimes stalls The most common culprit? Oil contamination in the fuel. Oil contamination in heavy-duty NGVs can be hard to diagnose and even harder to remedy—especially […]
Diagnosing Low Power in Heavy-Duty Natural Gas Engines
By Gordon Larsen and Bill Marchetti, NGVi Technical Instructors In NGVi’s work training heavy-duty natural gas vehicle technicians, the number one problem they report is diagnosing low power conditions. When a Cummins-powered heavy-duty natural gas vehicle is brought into the maintenance facility with a complaint of low power, the technician wants to diagnose and repair the problem […]
Basic Safety Practices for CNG Technicians
By Kasia McBride, Marketing Manager, NGVi Every technician who works on or around CNG vehicles should be familiar with the basic safety concerns for these vehicles. While CNG has three main hazards, including high pressure, fire and asphyxiation, the primary hazard is high pressure. This is because the nominal fill pressure of compressed natural gas […]
Tech Series on High-Pressure CNG Fuel Systems: Part 3- Pressure Relief Devices
By Kasia McBride, Marketing Manager, NGVi While CNG fuel systems are extremely safe, due to stringent manufacturing requirements, it is essential that NGV technicians fully understand the specific standards that apply, and know how each component within the fuel system should operate. This article explores pressure relief devices (PRDs), and is the third in […]
Tech Series on CNG High-Pressure Systems: Part 2 – High-Pressure Fuel Lines and Fittings
By Kasia McBride, Marketing Manager, NGVi This article is the second in a series, providing technicians who will be diagnosing and repairing NGV fuel system components with useful information about characteristics, maintenance and requirements of different components included in the high-pressure side of the CNG fuel system. High-Pressure Fuel Lines and Fittings The high-pressure tubing […]
Tech Series on CNG High-Pressure Systems: Part 1 – Fill Receptacles
By Kasia McBride, Marketing Manager, NGVi Since one of the main characteristics of CNG vehicles is their high-pressure fuel system, NGV technicians are required to fully understand specific safety standards and procedures and know how each component within the fuel system should operate. Specifically, the high-pressure side of the fuel system includes the fueling […]
How and Why Is Oil Getting Through Your Vehicle’s Coalescing Filters?
By Robin Skibicki, Marketing Coordinator, NGVi Oil carryover is a major concern for anyone owning, operating, servicing and/or maintaining natural gas vehicles (NGVs). Oil present in a natural gas powered vehicle can result in hard starting, rough idling, hesitation under acceleration, or stalling. The oil typically comes from oil used to lubricate the compressor(s) […]
Pressure Relief Devices Recalled
By Kasia McBride, Marketing Manager, NGVi Recently, more than 67,000 pressure relief devices (PRDs) used in CNG fuel systems were recalled by Circle Seal Controls, which is a unit of CIRCOR Aerospace. The issue was reported last year by Hexagon Lincoln, after one of its customers, New Flyer, noticed a leak. This leak was traced […]
Understanding HPDI Natural Gas Fuel Systems
By Paul Pate, Training Manager, NGVi There are two different types of natural gas engines and systems for the heavy-duty natural gas market: spark ignited and compression ignited. Spark-ignited systems are by far the most numerous, and account for more than 90% of the market. There is a limited number of compression-ignited systems available. These […]
