Natural gas vehicle (NGV) engine manufacturer Cummins Westport Inc. of Vancouver, BC, has recalled two of its dedicated NGV engines, the 8.9-liter ISL G, and the 11.9-liter ISX-12 G for a software fix.
This winter's bitter cold weather helped identify the problem of elevated exhaust temperatures that led to at least two tailpipe fires in January. It is suspected that frigid temperatures led to improper operation of exhaust sensors in the engines.
"Condensation in the intake manifold may freeze during cold weather conditions and interfere with the proper operation of the intake manifold pressure sensor," said the National Highway Traffic Safety Administration (NHTSA).
Federal officials said Cummins Westport stepped up immediately when the problem arose and has recalled 22,554 ISL G engines made between Sept. 12, 2007 and Feb. 2, 2014, along with 2,554 ISX12 G engines manufactured between Feb. 19, 2013 and Feb. 2, 2014.
Cummins Westport said the correction involves recalibration of the engine control module to be provided at no cost to the vehicle owner/operators. The work will be done by the Cummins service network.
A new piece of calibration equipment, an ECM, has improved the diagnostics to detect an improper manifold sensor condition during freezing conditions, the NHTSA said.
Earlier in the year (see Daily GPI, Jan. 13, 2014), Cummins Inc. decided to "pause" the development of its 15-liter spark ignition engine for at least the first six months of this year, citing the need for more fueling infrastructure. Industry sources, however, said this should not slow the development of more long-haul trucking moving to NGVs.
According to NHTSA, the ISL G engine had been shipped over the years to 51 original equipment manufacturers (OEM), including 15 Cummins distributors; and the ISX12G had gone to 10 OEMs.
On a more positive note, Westport Innovations touted a new development agreement with Delphi Automotive to improve Westport's high-pressure direct injection (HPDI) that is considered a leading NGV technology platforms for heavy-duty engines.
Westport and Delphi have agreed to co-develop and manufacture high-pressure natural gas fuel injectors for multiple OEM engines, including the injectors for Westport's HPDI 2.0.
Elsewhere, composite truck body manufacturer BrandFX introduced a light-body configuration that cuts more than half of the weight of three compressed natural gas (CNG) tanks for dedicated F-250 trucks. The composite service body for the trucks has a weight of 698 pounds, 538 less than a comparable steel body chassis. The composite bodies are touted for extending the life and the service performance of the vehicles, according to their backers.
In another first in the CNG sector, construction equipment supplier Terex Corp. rolled out the first CNG-powered cement mixing trucks, sporting 11.9-liter ISX12 G Cummins Westport engines, one of the two recalled. The cement trucks use a two-CNG tank design.