Everyone is looking at ways to stretch their fuel dollar. With (over the road) diesel prices at the time of this writing hovering about $4.90/gal, I spend a lot of time looking at alternatives. I found one that looks particularly interesting that I'd like to share with you my loyal readers...
“The Fuel Stretcher” is a new device, developed my DeLuca Fuel Products that allows
the use of
supplemental propane or compressed natural gas on turbodiesel engines. When propane
or cng is
injected into the air intake of a turbodiesel, it reduces the
amount of diesel fuel necessary to produce the needed power. It
is basically substituting propane or cng for some of the diesel fuel.
This is also called fumigation. The engine must always use
some diesel fuel, because the diesel fuel ignites the gas.
The Fuel Stretcher allows the user to adjust the amount of gas
consumed from very little to approximately two to three gallons
of gas to every gallon of diesel fuel. This can amount to
a substantial reduction of the operating cost per mile.
The gas also increases the power output of the engine. Another
side benefit is much lower emissions and less lubricating oil
contamination.
The Fuel Stretcher comes as a complete kit with easy to follow instructions for installation. The only additional item you need is a propane or cng tank.
Since the price per equivalent gallon (GGE) is significantly less than diesel prices, the economics are very attractive. When the CNG tank runs out and you have plenty of diesel left, the system simply reverts to burning diesel. Many people who have done CNG (not DeLuca specific) conversions find they are able to cut fuel costs by approx 10%, while reporting abundant extra pulling power. With or without a heavy load, the sources I follow report increases in power throughout the whole power curve, and crisp shifts. The best examples I've heard associated with these types of conversions relate to the increase in power when heading up the long grades. Others report, as an additional bonus, driving range increases for every tank of diesel. Seems like a reasonable thing to consider.
A GGE (or Gasoline gallon equivalent) is the amount of alternative fuel it takes to equal the energy content of one liquid gallon of gasoline. We can use compressed natural gas (CNG) as an example here. Since CNG is a gas rather than a liquid, its volume is measured in cubic feet (CF), rather than in gallons. Therefore, GGE is a way of comparing equivalent amounts of fuel based on their energy content (here we will use British Thermal Units (BTU). One GGE of natural gas is 127.77 cubic feet. This volume of natural gas has the same energy content as one US gallon of gasoline (based on lower heating values: 900 BTU/CF of natural gas and 115,000 BTU/gallon of gasoline)
Theory of Operation
With the DeLuca conversion, no gas is used when the engine is idling. A hose is connected from the regulator to the air intake between the air cleaner and the turbo. When the engine load increases, the turbo creates an increasing vacuum in the air pipe. This vacuum activates the propane regulator to begin supplying fuel. As the engine load continues to increase, the vacuum continues to increase, causing the regulator to supply more and more gas. A ball valve in the fuel vapor line controls the overall fuel curve. The in-cab adjuster for this ball valve allows for adjustments while driving. A dash mounted switch turns the unit on and off, and it also turns on and off with the ignition switch. The unit draws liquid propane from the tank to eliminate pressure loss due to evaporation within the tank. Consequently, the unit is water heated and is connected in series with the heater core. The kit includes all necessary hoses and hardware to make this connection.
DeLuca cites operation on a GM Duramax has given as much as 60 miles per gallon of diesel fuel. At this consumption rate, the propane consumption was approximately 20 miles per gallon. Another great benefit is that it will add up to 100 rear wheel horsepower. CNG, (compressed natural gas) is now available to supplement diesel fuel for turbodiesels. Comparable results to propane have been achieved.
It’s really a serious concern that the number of diesel mechanics is shrinking in the country day by day. If people consider this job uncomfortable then they should adapt new technology then it would be an easy job.
Posted by: Diesel mechanic | September 09, 2011 at 07:03 PM