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Topic: Propane Or Natural Gas Injection System On Diesel Engines (Read 1143 times) previous topic - next topic

Propane Or Natural Gas Injection System On Diesel Engines

I have been researching the new injection system by injecting LP, Propane gas into the modern Cumins or Cat engines. Appears that it is really getting attention with buses,  city garbage trucks and many other. The results are really impressive. The system is very simple and not very costly. The power & mileage increase is impressive along with longer oil changes. Anyone looked into this. Thanks C.Lacy - Houston

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #1 –
My cousin's husband in Montana is in the business. He can get your motorhome converted.
George Stoltz.  Retired from full-time living in a great Foretravel and now are back to living in a traditional sticks and bricks in Florida.

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #2 –
Let's clarify-- some ADD propane injection to their diesel which continues to burn mostly diesel to add power.

Some diesel engines are designed to run on other fuels such as propane or natural gas.

Which are you interested in?

Brett
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #3 –
Clarence

You probably mean to supplement the diesel fuel with the addition of a small amount of propane. Propane has approx. 91K btu/gal vs. diesel at 135K btu/gal. Your home propane supplier can fill your tank for around $1.95/gal vs. $4.25/gal for diesel so a percentage of propane injected may drop your total cost a little per mile. The problem here is the cheap propane pays no road tax much like using dyed diesel in your RV. When you purchase propane on the road, the per gallon cost goes way up, At $3/gal for propane, the cost per BTU is going to be close to the same. And that is what we are talking about, the number of BTUs it takes to push your RV a mile whether a diesel fuel BTU or a propane BTU. If you inject a larger percent of propane, you engine may produce more HP but also more heat. Propane will auto explode before the diesel fuel is injected so engine damage could easily occur if too much is introduced. I don't know how the modern computer controlled diesels will handle supplemental propane but a poor installation, misuse or an unexpected glitch could cost you a bundle or at least shorten the life of your engine. The bus and trucking companies using alternate fuels operate in a very controlled environment with extensive testing and record keeping.

When a higher mpg claim is made, does it include the total of both fuels consumed? Easy to miss this one.

No magic bullet for getting your rig from A to B cheaper. I wish there were.

Pierce & Gaylie
'93 U300/36
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #4 –
On our big 'ol diesels, propane injection might work fine.  We previously had a coach with a 4 liter Isuzu, and propane injection was popular on the anemic engines.  That is until people saw what it did to the engines - normally good for 300k to 500k, they were breaking down well under 100K.  One guy kept replacing harmonic balancers that "inexplicably" blew apart every 10k or so.

Research carefully before you proceed!  Again, it may be fine on bigger diesels.

oldMattB
Matt B
1998 u-320

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #5 –
Quote
If you inject a larger percent of propane, you engine may produce more HP but also more heat.
When we were looking for a Foretravel we checked out a 280 at PPL in Houston. It looked good and we were considering it. In looking more closely, we discovered that this coach had had a propane injection system installed. Then we found the paperwork which the previous owner had left in the coach. It showed a history of overheating issues with some kind of misting system installed to overcome the heating issues. Anyhow, we passed on that one.
jor
93 225
95 300
97 270
99 320

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #6 –
The main idea is increased mileage by 3-5 mph & more power. I know this is fairly new to most but I am in the process of contacting companys which are running large fleets of trucks on the road and in town. The heating issure is not correct - the injection process has to be installed by a professional and properly set - the propane injection actually drops the temp. We presently have a glut of natural gas and is going to be the fuel for trucks and autos of the future. CL

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #7 –
Should the itch ever strike me, for my Cummins 5.9 BTA a bigger turbocharger and bigger injectors could produce gobs of power without adding a second fuel system. The marine folks love souping up 5.9s and Cat 3208s, among others. I've casually poked around the marine engine builder sites. As always - speed costs money. How fast do you want to go?  ;)

Many years ago I drove a propane powered cab on weekends while going through school. It did run clean - oil looked like new after 5000 miles. However, it did use more volume of fuel than it would with gasoline. At the time propane was a lot cheaper than gas, so it was practical. Once outside the city, though, fuel could be hard to come by. And it could be a bugger starting in below freezing temperatures.

Would be curious to see how it turns out if you do go the propane injection route.

Steve
1991 U225 Grand Villa

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #8 –
Quote from: Clarence Lacy –
The main idea is increased mileage by 3-5 mph & more power. I know this is fairly new to most but I am in the process of contacting companys which are running large fleets of trucks on the road and in town. The heating issure is not correct - the injection process has to be installed by a professional and properly set - the propane injection actually drops the temp. We presently have a glut of natural gas and is going to be the fuel for trucks and autos of the future. CL

I had looked at Propane about 18 months ago. Mostly what I found was conflicting reports. I came to a conclusion much like that of Clarence but I am not certain enough to move forward with Propane. Clarence, please keep us informed of the outcome of your investigation. I have a feeling finding a way to reduce fuel costs will become much more important in the next few years.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #9 –
jor,

I saw the same Foretravel you did at PPL.  It had a LOT more work than just the injection of propane.  It appeared that the head had been "flowed", there was a larger intercooler and they added "ram" air intakes, I also suspect it had a hotter cam.  I was told by PPL that the power had been increased by 60 HP as it was needed for mountain driving.  My guess was the coach was pulling a fairly heavy load and it was getting a real workout.  In essence, it had been hot rodded with out the necessary increase in cooling capacity.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #10 –
Quote
saw the same Foretravel you did at PPL.
Oh, yea, thanks, John. I had forgotten about the intercooler and the ram deals. I have a bunch of photos of that rig around here somewhere. I recall reading that the guy had gained a lot of power. Interesting that the propane actually lowers operating temps. I didn't know that. I recall back in the 80s it seemed like half the pickups coming across the Mexican border had big propane tanks in the bed. It was dirt cheap in Mexico.
jor
93 225
95 300
97 270
99 320

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #11 –
For anyone interested in more info on the propane injection system you can go to : dieselperfproducts@earthlink.net
Keith Long - powershot 2000 system. Thanks Clarence

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #12 –
The pickup trucks you see coming across the border with big propane tanks are 95% gasoline conversions. Propane is only about a buck a gallon down there so you can't go wrong. It is MUCH easier to control the ignition of the gas with a timed ignition rather than just injecting it into the intake and letting air temperature, engine temperature, altitude, engine condition dictate when the propane is going to explode. This leads to detonation and resulting engine damage and is why a lot of propane conversions don't work out in the long run. Also, propane or Natural gas contain much lower energy per gallon plus you need a really thick walled (read heavy) tank to contain natural gas in a liquid form.

The older diesels injected the diesel at 3000 to 4000 psi. The new computer controlled common rail injection systems spray diesel into the combustion chamber at 35,000 psi. They can spread the timing and volume of the spray very accurately over a period of several degrees. This is why a new 5.9 Cummins is whisper quiet compared to an older 5.9 with a mechanical pump and has much lower emissions.

We are the middle-east of natural gas in the world. It could easily be used to replace gasoline in all of our spark ignition engines with much lower emissions, etc. While it has a place augmenting diesel fuel in a compression-ignition engine, it will be difficult to implement direct high pressure injection of propane, CNG or any other combustible gas into the combustion chamber with the degree of accuracy needed. A more likely solution is bio-diesel that can be made from algae, turkey and chicken parts, plant material. This will keep the product in liquid form and can be substituted for the petroleum product we use now with major emission advantages. Spark ignition engines will never be able to get much over 30% efficiency while compression ignition 2 cycle engines like Fiat and Mann are achieving 55% efficiency in ships now (on 155,000 BTU/gal. bunker fuel).

Pierce & Gaylie
'93 U300/36
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Propane Or Natural Gas Injection System On Diesel Engines

Reply #13 –
Quote from: Pierce & Gaylie Stewart –


We are the middle-east of natural gas in the world. It could easily be used to replace gasoline in all of our spark ignition engines with much lower emissions, etc.

Yep, ain't it the truth.  All the half baked efforts to produce efficient cars here in the US, hybrids with their complexity, all electrics like the Volt which, in truth, really runs on coal as thats what produces the majority of the electricity it runs on, when all that's really needed are home size natural gas compressors and small pickup trucks with the fuel tank in the bed.  Way too simple.
"Not so  long ago we were a nation of risk takers, riding five million pounds of  thrust straight into space."  Joe Gresh
Chuck Pearson
1996 U295
2018 Can Am X3 TurboRS