busride maintenance november 2012
DESCRIPTION
The exclusive maintenance resource for the transit and motorcoach industry! November's cover story: ABC Companies repower program underwayTRANSCRIPT
T h e E x c l u s i v e M a i n t e n a n c e R e s o u r c e f o r t h e T r a n s i t a n d M o t o r c o a c h I n d u s t r y !
NOVEMBER 2012
ABC Companies repower program underwayPage 6
November 2012 @ BUSRide Maintenance 3
NOVEMBER 2 0 1 2
C O N T E N T S6 A re-powerful solution to engine woes ABC Companies Repower Program adds value and miles to older equipment By David Hubbard
8 It’s time to winterize Thermo King provides HVAC maintenance tips and checklist By Steve Johnson
10 OEM is the right choice Bendix Spicer Foundation Brake addresses aftermarket brake linings By Gary Ganaway
13 Drive on and lift off SEFAC adds OMER Pantograph lift to product line
14 Three action items to prepare for winter Troubleshooting HVAC requires an interrogation of the system By Robert Buchwalter
15 Cummins Westport developing ISB6.7 G Natural Gas Engine To target school bus, medium-duty truck and vocational vehicles
DEparTmENTS 4 Editorial Advisory Board Commentary BUSRide Maintenance looks to 2013 By David Hubbard
5 Maintenance Tip of the Month Make it their shop not yours
By Ron Anderson
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Publisher / Editor in Chief Steve Kane
Associate PublisherSali Williams
Editor David Hubbard
Assistant EditorRichard Tackett
Director of SalesJennifer Owens
Account Executive Maria Galioto
Production Director Valerie Valtierra
Art DirectorDominic Salerno
Contributing WritersDoug Jack, Matthew A. Daecher
POSTMASTER: Please send address changes to:
BUSRide • 4742 North 24th Street • Suite 340Phoenix, Arizona 85016
Phone: (602) 265-7600 • F: (602) 277-7588 Web site: www.busride.com
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Reprints:All articles in BUSRide are copyrighted and may not be reproduced in whole or in part without the express written permission of the publisher. For reprints of 100 or more, contact Valerie Valtierra at (602) 265-7600, ext. 203.
BUS industry SAFETY council
Accountant
Fred ValdezVice President
Operations Valerie Valtierra
Beginning in 2013, owners, operators and bus and coach technicians will find BUSRide Maintenance folded into their monthly issue of BUSRide. This insert will be easily removable for anyone who wants to take to the shop.
Our mission remains the same: Connect with the bus and coach industry from the maintenance side. Whether it is drudgery for some and pleasurable for others, bus and motorcoach maintenance is growing more varied and complex and commands our attention more than ever. That is why we think BUSRide Maintenance continues to need its own front cover and exclusive editorial.
BUSRide Maintenance is for everyone in the industry in need of an informative view from their fellow mainte-nance directors, supervisors and bus and coach techni-cians who diagnose the problems and get them fixed. Equally important are the previews of the OEMs and ven-dors that provide the equipment and services that make vehicle maintenance safer and more efficient.
We will continue to invite editorial contributions from qualified professionals in every area that touches on maintenance — mechanical, technological, administra-tive, management and training. BUSRide and BUSRide Maintenance continually seek commentary, instruction and advice on best practices to keep all the equipment — motorcoaches, transit buses, paratransit vehicles, small bus shuttles and trolleys — on the road and run-ning safely.
With coverage on the install and repair of every sys-tem and component stem to stern on buses of every ilk, the goal for BUSRide Maintenance is to leave no stone unturned as we plow through the many aspects the main-tenance crew faces on a daily basis.
David Hubbard
A look to 2013
Editorial Advisory Board Commentary
November 2012 @ BUSRide Maintenance 5
Make it their shop not yoursThe most productive management philosophy is the one that
allows capable employees to do their work and accomplish their goals. The best managers know how to stay out of their way. Easier said than done, but it works at The T. Most of the technicians started on the low rung and worked up to their present positions, which has allowed me time to get to know each of my employees and how they work.I have put these four practices in place to ensure each employee works to his strengths and functions as a team member. I continually see positive results from these four simple steps.
1. Establish a solid team of trustworthy employees capable of taking instruction. 2. Give all shop employees job descriptions so they know what is required and what is expected. 3. Implement policies and procedures for the daily operations. 4. Hire a shop foreman who understands how to get the most productivity and efficiency from the technicians.
tipoftheMonth
Ron Anderson Director of Maintenance Fort Worth Transit Authority“The T” Fort Worth, TX
6 BUSRide Maintenance @ November 2012
When Caterpillar left the highway engine business
a few years ago, a number of operators looked at replacing their CAT diesel engines with other brands. As luck would have it for Bill Torres and DC Trails, Lorton, VA, about the same time the CAT in his pre-EPA 2007 C2045 Van Hool failed, ABC Companies was launching its engine re-power program in early 2012 at its facilities in Faribault, MN, Orlando, FL and Nappanee, IN. Torres saw his misfortune as an opportunity to test the waters.
“I had actually wanted to try out the Detroit Diesel (DD) engine and Allison
Transmission,” says Torres. “This was the perfect scenario to trade out the CAT and ZF transmission. I have absolutely no complaints, and am very impressed by how ABC Companies was able to fit a DD and Allison system into the compartment originally intended for a CAT.”
Torres says the repower process on the C2045 took about a month and a half, with the work done at the ABC Companies service center in Orlando, FL.
When he got the 2007 coach back, he sent a 2006 C2045 to Orlando for the same treatment.
Empire Coach Lines, Orlando, FL, recently re-powered three 2006 Van Hool C2045’s with Detroit Diesel/Allison power
trains. Empire Coach Lines Vice President Eddie Serrano says the change out allows his company access to aftermarket support from suppliers with long-term commitments to the motorcoach industry.
With the situation with Caterpillar creating issues for coach operators, ABC Companies says it stepped up to the plate to provide an affordable alternative.
“A large number of CAT operators have looked to ABC Companies for repower solutions,” says Lee Loper, ABC Senior Vice President, Refurbishment. “We’re pleased to be able to offer them repower services for Van Hool coaches as well as select MCI models.”
Detroit Diesel ships the fully warranted
A re-powerful solution to engine woesABC Companies Repower Program adds value and miles to older equipment By David Hubbard
6 BUSRide Maintenance @ November 2012
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remanufactured engines used in the repower program directly to ABC Companies from the factory.
According to Ed Harmon, ABC Director of Operations, the program is flexible enough to handle a variety of engine and transmission combinations.
“We have assembled several kits to accommodate all customer preferences,” says Harmon. “Some want to go with the Detroit Diesel engine but stay with the ZF transmission. Others want to change out to the Allison.”
In response to customer requests, Harmon says ABC Companies is also
repowering the engines from select pre-owned coaches the company takes in on trade and refurbishes for resale.
Steps in the process Coaches arriving in the shop undergo
a complete health check of the existing engine and transmission for potential resale.
The engine and transmission are removed, along with all connections to include harnesses and controls, and work begins on preparing the coach to receive the new powertrain. The process requires relocating the motor mounts to
accommodate the DD engine. Repowering also means new engine
and transmission control systems that recognize the new componentry. The update includes the J1939 communications multiplex system, along with the required software to run the electronics.
“All the electronics need a reset,” Harmon says. “For example, the cruise control function must meld with the correct transmission. The new transmission electronics must be able to detect the gear shift selection and the position of the throttle pedal.”
With the work complete, the coach and new power train undergo a rigorous and thorough road test of up to 200 miles. Back in the shop the vehicle is put on the lift for a re-check of all the connections and fluid levels. The new engine gets one final inspection before delivery to the operator.
Harmon points out that a repowered coach comes back outfitted with all OEM or OEM-equivalent parts and components, listed with the same parts number as in the OEM parts book for that year and model.
“The repower offering is a great service to be able to offer to our customers,” adds Loper. “It’s one of a number of specialized refurbishment services available. The breadth of these services, as well as the speed in which projects can be completed, is what truly sets ABC apart in coach refurbishment.” BRM
7November 2012 @ BUSRide Maintenance
Opposite page, top: Completed repower with newly installed Detroit Diesel Series 60 engine
Left: Coach is reprogrammed via laptops for correct KIBES versions as well as Allison and Detroit software.
Bottom photo: After a through degreasing, the original engine is pressure washed prior to removal.
8 BUSRide Maintenance @ November 2012
With the busy holiday season just around the corner, transit authorities
and motorcoach operators are dusting off their checklists and winterizing their fleets from the tires up.
For HVAC system performance and reliability, there is no substitute for a proactive year-round maintenance strategy to prevent rather than fix problems. Fall is a good time to examine the approach to HVAC maintenance. Keeping pas-sengers safe and comfortable is always a top priority. Noth-ing spoils a good ride like a bus that is too cold, too hot, too drafty or too stuffy because the HVAC system breaks down or does not work properly.
Performing maintenance tasks at recommended intervals ensures that fleet operators stay on schedule, avoid break-downs and service disruptions, manage operating costs and achieve higher levels of passenger satisfaction.
Most public transportation authorities and motor coach companies perform HVAC preventive maintenance on the same schedule they use for the bus engine and chassis. They must consider the unique operating characteristics of an HVAC unit as part of an integrated service and mainte-nance strategy.
An inspection and routine service schedule based solely on miles driven may not accurately reflect the wear and tear on the HVAC system because the unit runs whether or not the bus is in motion. In fact, the heating components in the HVAC system work continuously to maintain comfort levels
It’s time to winterize
Thermo King provides HVAC maintenance tips and checklist
By Steve Johnson
Fleet operators should consider a fall-winter quarterly or 18,000-mile service interval that includes, among other steps, checking for proper thermostat function by using the air conditioner to cool the bus interior down and then adjusting the thermostat for the heating mode.
The return air plenum, shown here, houses a clean air filter which allows proper air recirculation, opti-mizing the quality of the air inside the passenger cabin.
November 2012 @ BUSRide Maintenance 9
It’s time to winterize
when the engine is idling in traffic on a cold day or making sched-uled stops to let passengers on and off, with the doors open. Not surprisingly, HVAC components like the blowers and water valves on buses operating in northern climates work particularly hard under these conditions.
Thermo King, a global leader in transport refrigeration and a brand of Ingersoll Rand, recommends a blended approach to preventive maintenance, which establishes service intervals based on both mileage and operating hours. The company has developed a comprehensive schedule of inspections and routine service tasks with recommended actions performed monthly or every 6,000 miles, quarterly or every 18,000 miles and annually or every 48,000 miles.
Consider local operating conditionsThis structured approach provides a solid platform for an ef-
fective preventive maintenance strategy. However, operators will also want to consider their specific operating profile when devel-oping an ideal schedule for their vehicles. For example, opera-tors in colder climates may choose to inspect and test heating components more often during the winter months because the implications of a system failure are more serious. Those in areas with high levels of airborne particulates may want to change air filters more frequently.
Following are some specific actions that fleet operators should consider during their fall-winter quarterly or 18,000-mile service interval:
Inspect all air filters and wash or change if necessary.• Visually inspect the heating system for evidence of engine •
coolant leaks.Conduct a running inspection and measure interior return • air temperature maintained at 70 degrees or above.In warmer climates, make sure that the air conditioning • system and fresh air ventilation components are working correctly. Visually and audibly check HVAC blower motors and aux-• iliary heater blower motors (if they exist) for proper opera-tion in the heat mode.Check for proper thermostat function by using the air con-• ditioner to cool the bus interior down and then adjust the thermostat for the heating mode. Check for proper operation of the driver’s heater and de-• froster unit.
Finally, the fall-winter season and the beginning of a new year are ideal times for operators to examine their preventive main-tenance approach and make sure that it continues to meet the needs of the organization.
An effective, proactive and well-executed maintenance strat-egy pays for itself many times as compared to a bus’ typically long operating life by reducing operating costs, improving reli-ability and creating a better experience for passengers, drivers and maintenance teams. BRM
A veteran of more than 30 years at Thermo King, Steve Johnson serves as product manager for large bus and rail heating with Thermo King, Minneapolis, MN, a brand of Ingersoll Rand, respon-sible for HVAC marketing and product management for United States coach and transit buses.
10 BUSRide Maintenance @ November 2012
OEM is the right choice When the federal government
announced stringent new reduced stop-ping distance (RSD) regulations for class 8 tractors, brake manufacturers responded. They developed more advanced foundation drum brake systems to help the commercial vehicle industry meet the new standards and improve highway safety.
The first phase of the new RSD stan-dards went into effect August 1, 2011, with the second phase taking effect August 1, 2013. The new high-performance drum brakes not only reduce stopping distances, they also perform better and with signifi-cantly less fade than their predecessors. While an increasing number of fleets are
meeting the new RSD standards with air disc brakes, today’s larger and more pow-erful foundation drum brakes – sometimes in combination with air disc brakes – are the most popular option.
Even as fleets and drivers have added these new drum brakes to their vehicles, however, many remain unaware that a rou-tine maintenance decision can negate the technological advancements and potentially compromise safety. Relining today’s high-performance drum brakes with aftermarket friction, and not the linings specified by the original equipment manufacturer (OEM), can significantly reduce a vehicle’s stop-ping capability, reduce the vehicle braking
Bendix Spicer Foundation Brake addresses aftermarket brake linings
By Gary Ganaway
The new high-performance drum brakes not only reduce stopping distances, they also perform bet-ter than their predecessors.
November 2012 @ BUSRide Maintenance 11
capability and may introduce a safety concern.
In today’s era of RSD-compliant drum brakes, the use of OEM replace-ment friction is vital to maintaining their effectiveness.
The necessity of OEM liningsSelecting the correct replacement
brake lining is important to the overall safety of the vehicle.
The Technology and Maintenance Council (TMC) of the American Trucking Association agrees, stress-ing in its recommended practices that it is essential the replacement brake linings function as well as the material originally supplied on the vehicle.
Engineering teams from Bendix and other OEMs work full-time to design and spec brake packages, taking into account factors such as axle rating load, wheelbase and tire size. They also specify the most effec-tive friction materials for use in those brakes, to create a comprehensive brake package with safety top of mind. The engineering in low-cost aftermar-ket replacement friction is not to the same standard.
OEM replacement linings designed for RSD-compliant braking systems perform significantly better than tradi-tional brake linings. When subjected to the temperature increases that occur during brake usage, OEM lin-ings also maintain their performance levels much more effectively.
Beyond FMVSS 121There is significant confusion over
friction replacement because of the test procedure known as federal motor vehicle safety standard (FMVSS) 121. There are two components of FMVSS 121 criteria: dynamometer and vehicle stopping distance performance. The dynamometer test is outdated in the new RSD environment.
Unfortunately, the transit industry still considers passing this test a seal of approval for replacement linings with the results often viewed as an indicator that a brake lining will supply the torque output needed to stop a
vehicle within the new standards. This is not necessarily the case.
In two key instances, the FMVSS 121 testing simply does not line up with new RSD standards. First, while the calibrations of the dynamometer test simulate conditions of a stop from 50 miles per hour, RSD regulations are based on measuring stops from 60 miles per hour.
Second, the new RSD rules require
brakes to achieve a deceleration force of .55 Gs — an increase from the pre-vious force of.37 Gs. The FMVSS 121 dyno test does not reflect this higher requirement. The laboratory environ-ment of the FMVSS 121 test is also unable to take into account the weight transfer experienced in a braking vehi-cle, particularly the addition of weight to the steer axle.
As the technology and mainte-
12 BUSRide Maintenance @ November 2012
nance council’s aftermarket brake lining classification report observed: Brakes relined with certain after-market materials can have reduced braking output, cause a shift of work to brakes on other axles, and reduce the overall stopping capability of the vehicle.
That same report bluntly states that the FMVSS 121 testing of small lining samples “is not considered accurate in determining performance on a full size brake,” making it abun-dantly clear that this particular pro-cedure is no longer a reliable barom-eter of how a brake should perform in today’s RSD environment.
A 96-foot differenceBendix engineers compared the
performance of an RSD-compliant vehicle with OEM brakes and linings
to a popular aftermarket material that passed the FMVSS 121 dyno test but was not suitable for RSD compliance. Using computer simulation software and with nothing else changed, the vehicle’s stopping distance showed an increase from 215 feet using the OEM friction to 311 feet with the aftermarket replacement friction – a stunning 45 percent decrease in per-formance.
While the new RSD regulation does not alter the stopping distance requirement for motorcoaches, which remains 280 feet at 60 mph, it is clear that the use of inadequate fric-tion can still pose a potential safety risk with existing regulations.
That 96-foot difference in stopping distance is a stark illustration of the roadway safety at stake, particularly for motorcoach operators and the
people who depend upon them for transportation.
Because there is no regulatory on the road testing of braking in action, drivers of vehicles using aftermarket replacement friction will not know whether their new linings have com-promised their stopping power until a real-world situation calls for it. An emergency stop is no time to find out.
When it’s time to replace brake linings, motorcoach operators should look to their brake supplier and reline with OEM friction. By doing so, oper-ators can maintain RSD-level brake performance and safety levels. BRM
Gary Ganaway serves as director of marketing and global customer solutions for Bendix Spicer Foundation Brake LLC, Elyria, OH and Kalamazoo, MI, with a manufacturing facility in Bowling Green, KY.
OEM continued
November 2012 @ BUSRide Maintenance 13
While the history of SEFAC dates back to the late 1880s, its heavy-duty mobile lifts do not appear on the com-pany timeline until 1968. Moving from Europe, SEFAC entered the American market in 1976, becoming a privately owned U.S. corporation in 2005. Man-ufacturing lifts for heavy-duty buses and motorcoaches, SEFAC was known for its signature electromechanical self-locking design based on an Acme threaded screw and a bronze load nut. The company says it was the first mo-bile lift company to obtain third party certification by the Automotive Lift In-stitute (ALI) standard.
Portable SEFAC lifts accommodate motorcoaches, school buses, regular length and articulated transit using a set of four or six columns for each type of vehicle within a gross vehicle weight range of 18,000 to 50,000l pounds per column.
“Since we manufactured our first lift nearly 40 years ago, we have remained committed to the principals of a guar-anteed self-locking threaded screw,” says SEFAC President Allister Collings.
“Without the application of power it cannot move, and unlike a hydraulic lift it does not rely on a locking mechanism to grab the load in the event of a failure. Additionally, a screw lift is proven to last longer than a hydraulic lift and is more environmentally friendly as they will not leak hydraulic oil.”
Lifting a motorcoach on four columns typically requires a lift rated at 18,000 pounds due to the weight at the rear and, considering a large proportion of the weight can overhang the point of lift on the forward tag axle by as much as eight feet.
The design of the lift is important as it determines the suitability of the lift to handle this overhang, according to Collings. He says on a SEFAC lift the carriage rollers are captive within the column, meaning they can handle this overhang.
“A SEFAC lift takes up no more room than the vehicle being lifted and pro-vides unobstructed access to vehicle underbody,” he says. “If the lifts are not required for vehicle maintenance duties they can be stored in a compact area.
Drive on and lift off SEFAC adds OMER Pantograph lift to product line
OMER designs and builds platform style heavy-duty lifts for
transit vehicles, buses, trucks and industrial equipment.
SEFAC promotes OMER lifts According to Gary Mason, SEFAC vice
president, Sales, while the industry will al-ways know SEFAC for its mobile lifts, the company opted to promote OMER lifts in its product line for those customers who need a fast, easy-to-use drive-on lift for quick turnaround jobs. He says the lifts are available in capacities up to 99,000 pounds and runway lengths up to 48 feet.
OMER designs and builds platform style heavy-duty lifts for transit vehicles, buses, trucks and industrial equipment, drawing on proven engineering principals it says date back to the 1600s as evidenced in the “K Series” pantograph lift. Mason says the OMER lifts fall under the SLEC brand.
“The pantograph lift raises the vehicle vertically,” says Collings. “This function saves as much as five feet of floor space compared to a parallelogram lift which ris-es at an arc. It has no mechanical cross-beams linking the runways, which makes it very easy for operators to wheel tools, an oil drainer or transmission jacks under the vehicle.” BRM
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14 BUSRide Maintenance @ November 2012
Three action items to prepare for winter
We made it through the AC season, but this is no time to rest on accomplish-ment. Winter is coming, which brings an increase in write-ups related to the heat-ing system and a seasonal shift in thinking from keeping passengers safe and cool to safe and warm.
When the first rounds of “no heat” com-plaints begin coming in, the first step is to verify the problem.
Today most drivers operate a variety of buses and coaches in anyone fleet, mak-ing it necessary to ensure they are trained and comfortable in operating and control-ling the different heating systems. When heating problems arise, it is possible the driver has never been trained in the proper operation or is unfamiliar with a new con-trol system.
The maintenance side has its own set of responsibilities in clarifying the problems. A few questions will usually get us started. Is the driver heater core putting out heat but leaving the passengers cold or vice versa? Does it heat initially but gradu-ally fade? Is there no heat at slow speeds but kicks in at highway speeds? Is there more heat at the rear of the bus than at the front?
By spending a few minutes interrogat-ing the heating system, we can focus our troubleshooting and reduce the diagnostic time.
We need to understand the configura-tion of the system in that coach. Are there any valves that can create the problem? Are the valves open? Are they ball valves or gate valves? Which way is open, which way is closed? Most buses have manual cutoff valves designed to stop the flow of coolant into the heater cores.
During the summer months, these valves must be shut. This is not a problem in warm weather, but becomes evident as we move into fall. Simple items, to be sure, but these are checks we need to make. The first action item this month should be to clearly identify the location and opera-
tion of these cutoff valves and ensure ev-eryone in the shop has this information.
Also, once a valve that had closed is opened, the technician should determine why it was closed. It is not enough to just open the valve and send the bus on its way. Did the driver close this valve be-cause of a coolant leak out on the road? Once a manual valve is opened and the coolant flow re-established, we might then discover a leak up near the heater cores. We need to look a little deeper into these situations. Also closely related to the valve condition are the proper hose routing and bypass valves.
Prevost coaches have a fairly conven-tional heater circuit, but some OEMS with roof and floor radiant heating are more complex.
It is necessary to obtain the proper doc-umentation to be sure all the hoses are not mixed up and going to the proper ports. The more complex the heater circuit, the more valves. Are there bypass valves that allow hot coolant to return to the en-gine without travelling to the heater core? Which valves on the heater circuit are N.C. and which are N.O.?
How about the boost pump? It is one thing for a pump to be turning and another for the impeller to be turning. Though the shaft may be turning, the impeller can sometimes loosen, with the result being no flow of coolant into the core. A visual and physical inspection will verify the pump’s operation. If the pump is not operating, we need to look at its electrical control and supply.
If the pump is turning, is there anything that might restrict the flow of coolant? Does the coach have filters or strainers on the heater circuit? For many years, Prevost coaches had a small strainer just upstream of the heater control valve in ad-dition to the engine coolant filter. If this is not maintained and becomes blocked, the engine cooling system will operate proper-ly but there will be no hot coolant delivered
to the heater core. Make sure there is full circulation of coolant to the heater cores.
Of course, check the heat source itself. Does the engine achieve proper tempera-ture? If the engine runs cooler than nor-mal, is there a problem with the thermostat or do we have an incorrect thermostat? Today’s engines are designed to run hot-ter than in years past, which require veri-fication as to the type of thermostat to be installed.
Therefore, the next action item should be to locate in the manuals the correct thermostat specification for all the buses and coaches in the fleet. The proper ther-mostat not only affects the heating system but links to the emission controls as well.
The operation of the engine cooling fan is closely related to the thermostat. The ECU controls the fans in today’s engines because fan operation and temperature control is also closely related to the emis-sions controls. A road test while monitoring the engine ECU with a laptop will confirm the operation of the fan. Earlier vehicles controlled the fan through a separate tem-perature sensor system, which could be bypassed to lock the fan in to a running condition. A fan running when it shouldn’t can prevent the engine from reaching proper temperature.
Finally, the coolant must be the proper coolant for each engine. There are differ-ent brands and types of coolant for differ-ent engine families. Make this the third action item for this month: determine the proper coolants for each engine and en-sure everyone who works on or drives the vehicles knows which coolant goes into which engine. And make absolutely sure that everyone in the shop along with all the drivers understands the difference in these coolants and the danger in mixing them. BRM
Robert Buchwalter serves as one of two Prevost technical field instructors conducting seminars at the Prevost factory in Quebec, customers’ shops, and transit agencies. He is a member of the BUSRide Editorial Advisory Board.
Troubleshooting HVAC requires an interrogation of the systemBy Robert Buchwalter
November 2012 @ BUSRide Maintenance 15
Troubleshooting HVAC requires an interrogation of the system
Cummins Westport developing ISB6.7 G Natural Gas Engine To target school bus, medium-duty truck and vocational vehicles
In an effort to expand its product range to supply growing demand for natural gas engines, Cummins Westport Inc., Van-couver, BC, Canada, has begun development on the ISB6.7 G, a mid-range 6.7 liter natural gas engine designed to meet the increasing demand for on-highway vehicles powered by lower
cost, cleaner and increasingly abundant natural gas. The company says its ISB6.7 G will be based on the Cummins
ISB6.7 diesel engine and will use Cummins Westport’s proven spark-ignited, stoichiometric cooled exhaust gas recirculation (SEGR) technology. Exhaust aftertreatment will be provided by a simple, maintenance-free three-way catalyst. The engine will run on compressed natural gas (CNG), however, the natural gas may be stored on the vehicle in liquefied natural gas (LNG) state or as CNG. The ISB6.7 G is expected to be in production by 2015 and will be designed to meet Environmental Protec-tion Agency (EPA) and California Air Resources Board (CARB) regulations in force at the time of launch.
“The addition of the ISB6.7 G will round out our family of high performance natural gas engines,” says Cummins Westport President Jim Arthurs. “It joins the 8.9-liter ISL G, with over 16,000 engines in service, and the 11.9-litre ISX12 G, which will start production in 2013, to give our customers a broad range of natural gas engines for on-highway applications.”BRM
