But before you read this,just think a diesel engine with no emissions control on it...

As natural gas has become increasingly available, Cummins has been developing a full line of natural gas engines, both through its engine business and through Cummins Westport Inc. The joint venture partnership was established with Westport Innovations Inc. of Vancouver, British Columbia, in 2001.

Cummins Westport’s natural gas engines are available as factory-installed options from more than 50 truck and bus manufacturers, establishing the joint partnership as the leading North American provider of natural gas engines for on-highway commercial vehicles.

The joint venture announced in early 2013 that it had received certification for its ISX12 G engine from the EPA, meeting both the agency’s 2013 regulations and new greenhouse gas and fuel efficiency rules taking effect in 2014. Limited production of the natural gas engine began in April, with full production to start in August 2013.

About five months earlier, Cummins Westport announced it had started development on another engine, the ISB6.7 G. The 6.7-liter natural gas engine is based on Cummins ISB6.7 diesel engine. The natural gas version is expected to be in production by 2015.

The engines offered by Cummins Westport range in size from 5.9-liters to the 12-liter ISX12 G now entering production.

Independent of the joint venture, the Cummins Engine Business Unit has been building natural gas engines for many years, especially in the Company’s High Horsepower business, primarily for power generation and gas compression customers.

Last year, Cummins announced plans to produce dual fuel engines from 800 hp to 3500 hp (597-2610 kW) for high-horsepower markets. The first in the product portfolio, QSK50 Tier 2 for oil and gas well servicing applications, will begin production in mid-2013, with other QSK Series engines to follow, including engines capable of meeting upcoming EPA Tier 4 Final emissions regulations.

Cummins projects that by 2020, nearly 30 percent of its high horsepower engine production will be natural gas due to the increasing abundance of the fuel and its relatively low cost.

Cummins is currently working on a natural gas version of the QSK95, a 95-liter engine unveiled in 2011 that will be the largest high-speed diesel engine the Company has ever built.

 

the cleanliness will probably make the motor-oil change interval pretty long, but, how to get enough fuel into the cylinder for a good flame? Same way as propane enrichment, with a little pulse of Diesel spray for ignition?

 

Ya know drove a isx cng for awhile and my company has had nothing but problems with them we have 2 in our fleet they have very little power constantly braking down 1 has had 2 motors in less than 150k and to many other things to name and yes the fuel is cheaper but you don't get the distance out of cng and the service intervals are shorter than standard diesel so at this point I would not recommend one but they are a good concept and hope they can get a handle on them.

 

Range would suck, unless the methane (CH4) can be compressed, liquified, and you can actually drive away with as many POUNDS of fuel as what your normal tankful of Diesel would have weighed. The trick, then, would be to reliably deliver as many milligrams of methane, by weight, as the milligrams of Diesel. If you try to do it by volume, you'll get an underfuel/underpower result. You need approximately the same number of carbon atoms into the combustion chamber as what would have been delivered by a pulse of normal #2 fuel. Seems like the metering would probably be a high-pressure nightmare, and the pulse duration would have to be considerably longer than that of a normal injection. Timing would probably be a cast-iron bastard to work out. OR, fog the methane into the intake air, as if you were carburating the situation (very, very inexact and imprecise, there) , and use a smaller-volume Diesel pulse to get an ignition. OR... to shorten the pulse duration to something similar to that of a "normal" Diesel, perhaps multiple injectors per cylinder, an even more complex delivery system, and still maybe need #2 to start the flame.

Or, just go around under fueled all the time and be mad at the lack of power.

What parts of the system were failing? Fuel delivery? Fuel metering? Ugly burn patterns resulting in spiky EGT's and shattered pistons, even though you might not have gotten burn temps that would melt the crowns? Seems like a at least for a while, assuming there's ever going to be a way to get it right. Might be better off polymerizing the methane into gasoline and Diesel, and calling it a day, rather than trying to force an engine to accept it. With gassers, you can get away with it. Carburation was never an exact science, to begin with. Hard to imagine getting it right with a Diesel.

 

There are more and more CNG trucks on the road, and more truck stops putting in CNG pumps. I say great the less diesel they use the lower the price/demand should be. Will all trucks go this way, doubtful at least in our lifetime, But just like bio diesel, its not the complete answer but it does lessen the amount of diesel fuel used across the country. And I suppose clean up the air a bit.

 

Go CNG

 

It never occurred to me that a NG engine could have a lot less emissions junk on it. Does that mean we could get better performance eventually?

If CNG was a path to better performance it could be a game changer.
automotive improvements begin on the track and make their way to the driveway.

We have so much of the stuff, if we just created an incentive for the end user the problems of tanks and availability would solve themselves pretty quick.