Can a diesel vehicle be converted to run on CNG?

Replies to This Discussion

Permalink Reply by Jeff on September 3, 2008 at 8:53pm

Daniel
Check out the most current copy of Diesel Power Mag. They have a Duramax that is a duel fuel in a competition and it has all the power and gets decent mileage.

Permalink Reply by Gerald G Flood on September 4, 2008 at 11:04am

Yes and no, how much is it worth to you? All the diesel engine manufacturers make CNG versions of their engines. Basically it is done by changing ignition from compression to spark. Diesel's already have the necessary high compression.
It all amounts to your return on investment; how much will it cost and when will I get a payback? Of course you also need to locate available fueling locations.
Good Luck!

Permalink Reply by DubleDeuce on September 8, 2008 at 2:50am

Hel;lo Daniel,

We love our power. I don't just need it for a hot rod. I have a couple of trailers that I pull for my construction business that weigh 10,000 and nearly 20,000 pounds. >>

This is why there will "ALWAYS be an England" and their will always be a need for diesel fuel.

Yes, you CAN convert your diesel to CNG. But like many technical problems, the wiz bangers have it all fouled up. The general idea it to utilize the naturally high octane rating of NG (130) and the high compression ratios found in the diesel to put the two together. BUT! If you are looking for GGE (gasoline gallon Equivalent) you will be sorely disappointed. It is TRUE that you can get comparable performance from a NG powered diesel, but you WON'T get comparable fuel efficiency from its use. Discounting for the lower price on NG this may not be an issue, but add in the conversion ticket and as Dirksen was once quoted as saying, "A billion here and a billion there and pretty soon your talking about some real money."

The BEST excuse for using NG in a diesel is the cleanliness factor. Thoe ONLY reason that the diesel has EVER been afforded the opportunity to run CNG was the factof serious research and sdevelopment work done in the oil patch in the 70's and 80's. The oil patch had an abundance of NG. So much so that they routinely flared it off. A company I was with then (Deutz Corporation) produced protype kits (difusers) to permit the ingestion of the gas into the cylinders and used the existing injection system to "set it off". It was called pilot ignition and it required a source of diesel fuel to make it work. The idea works. But now many diesel engine manufactures (remember, they sell IRON, not diesel fuel) have engineered their product with high energy ignition systems and electronic fuel control. Rudolph would float from his watery grave if he knew.

The Deuceman

Permalink Reply by rich rabe on September 8, 2008 at 9:07am

They can be but at a great expense , the compression is too high ( 18-21) to one in most cases.CNG has an octain rating of 110 - to 130 depending on what part of the country it comes from , it runs well on engines with 8 to 1 to as high as 12 to 1 compression ratio, NA , This means changing the pistons, for large industrial engines such as Cat they make the pistons , where the injectors screw into they make adaptore that allow fine wire spark plugs to be used, where the injection pump would bolt to the assesory drive case they bolt up a magneto to fire the plugs, you would have to contend with all the computer stuff, glow plugs, high pressure fuel rail , that I think a duramax has, and having the heads machined for spark plugs, and a complete ignitton system built independet of the computer and well as having the pistons manfactured and changed,,,lots of $$$$$, I sure would start with and older gasoline engine....... Rich Rabe

Permalink Reply by Douiglas Coleman on September 22, 2008 at 11:16pm

Check this site.
http://www.greencarcongress.com/2006/08/us_energy_provi.html

Several companies are producing systems that should be available fairly soon that produce duel fuel diesels that maintain their power while reducing cost and pollution and may increase the working life of the engine. They don't require any internal modifications because you still use a blend of diesel. And actually CNG runs best on motors with higher compression ratios (12-1). The dual fuel gasoline engines aren't as efficient or powerful because of their lower ratios (9-1).

Permalink Reply by Tom Sewell on September 15, 2008 at 9:09pm

Works great call me and I can explain
www.tulsagastech.com

Permalink Reply by Douiglas Coleman on September 22, 2008 at 11:07pm

Daniel,
Check this site. Several companies are producing systems that should be available fairly soon that produce duel fuel diesels that maintain their power while reducing cost and pollution and may increase the working life of the engine.

http://www.greencarcongress.com/2006/08/us_energy_provi.html

Permalink Reply by William Engwer on October 13, 2008 at 11:46am

Atlanta has been running a fleet of CNG powered MARTA buses since the '96 Olympics. They routinely drag a lot more weight than you do. One often overlooked upside to CNG power is that engines last MUCH longer, because gaseous fuel doesn't wash lubrication off of cylinder walls or dilute the lubricating oil in the crankcase. CNG engines running synthetic oils have been disassembled after 100,000 miles and have shown NO MEASURABLE WEAR. When vehicles stay in service longer before replacement, the total-life-cycle energy cost of the vehicle is also lessened, because it takes a lot of ergs to melt one down and start over. W.Engwer

Permalink Reply by John Reed on November 29, 2008 at 9:48am

www.omnitekcorp.com has what you need, but don't tell them it is for a vehicle in the USA or they won't sell it to you!

Permalink Reply by Mark Johnson on December 19, 2008 at 2:40pm

Yes, our http://www.JiffyGas.com does convert diesel to natural gas but you cannot switch back to diesel.

Permalink Reply by Randy Filkins on June 30, 2009 at 10:30pm

Daniel,
There is a conversion system now available in the US for a Bi-Fuel diesel/cng system. With this system, power loss is not an issue and at the press of a button you can switch from one fuel source to the other. This system offers many technology improvements not typically available on conversion systems that have been available in the USA. I can provide you with more information on request if you have not found your solution yet.
Randy
filkinsr@ajsresearch.com

Permalink Reply by Frank on November 30, 2009 at 9:08am

A diesel engine can be converted to run on CNG (much like LPG) and diesel dual fuel conversions are quite straightforward. Technocarb's EcoDiesel System can be installed on any turbocharged diesel engine and the work takes about 8-10 hours to complete by a skilled CNG system installer.