Btu content of diesel fuel The heating value or energy content is not a product specification for diesel fuel, so it is not measured for each batch. However, the specifications effectively limit the heating value to a relatively narrow range. A typical net heating value for low sulfur No. 2-D fuel is 130,000 Btu per gallon.

Is there going to be a test???

I touught it would change based on air/fuel ratio.

BTU is a heat measurment

BTU British Thermal Unit----- the amount of heat required to raise one pund of water one degreeF

make any sense now

Fuel Quality

A major percentage of all problems with diesel engines are related to fuel quality. Diesel fuel can sometimes vary from one shipment to another or from one area to another. Customers also switch from one fuel vendor to another and suppliers sometimes change the fuel they are offering. The three things that vary the most in diesel fuel are cetane, weight and viscosity.

Cetane is defined as the susceptibility of the fuel to self ignite. Acceptable cetane levels are between 40 and 45, however, very few fuel distributors advertise this since each batch may be different. Cetane can influence both starting and combustion roughness of an engine. High altitudes and low temperatures demand increased cetane number of the fuel.

The weight of the fuel or specific gravity plays a major role in the heat content of the fuel. Number 1 is a "lighter" grade while number 2 is "heavier" or weighs more per gallon. While the lighter fuel (#1) has a lower "cloud point" and may provide better starting in cold temperatures, the heavier fuel(#2) has better lubricating qualities and actually contains more heat units (BTU’s) per volume. Assuming the fuels are the same price, better fuel economy is obtained by using #2.

The third aspect of fuel to consider is viscosity. Since "lighter" (#1) fuel is less dense it becomes thinner when heated than the heavier #2 fuel. When this occurs more fuel begins to leak through the high pressure parts of the injection pump which actually caused the injection pump to pump less fuel. As the fuel temperature continues to increase, more fuel is lost through leakage and this results in a power loss of between 1% and 7%.

Taking all these things into consideration buying #2 diesel fuel is the best all around fuel for the diesel engine. There are fuel treatments available to deal with cold weather, low lubrication, qualities, and unknown cetane content of diesel fuel. Buying fuel from a reputable dealer is a good way to insure high quality fuel. The best ones seem to be places that move a lot of diesel fuel such as truck stops, etc. The only way to insure your fuel quality is to treat it yourself and since every tank may be different every tank will need to be treated.

Thanks-great explanation of fuel quality!

However, what are the best brands of diesel treatment products and what are the pollution effects by using treatments? My mission is to lower the black soot that comes out of the exhaust pipe.

man that was good reading thank you that's pretty cool.

Have you ever heard about "Diesel de luxe"?
It has a sligthly higher BTU than Diesel No.2. It's called Kerosin in Germany and it's used for military airplanes. Do not use kerosene ! It's not the same!

Kerosin gives you that black smoke without the need of bigger injectors- simply add more air and you will get more power. German military trucks get Kerosin , when Diesel No.2 is in short supply in the field.

Of course there is one bad thing : Kerosin contains lead as a grease aid.
Maybe my comment is a little bit off topic, but I thought it's a nice to know thing.

When you buy fuel how will you know what you need to add...do you have to test it? Nice post btw.

In Germany a cetane number of 51 is standard, 49 is minimum. Size 4 years you can buy ultimate diesel which has a cetane number of 60. They advertise a noticeable power gain and a better fuel efficency, but in the real world the only remarkable difference is a smoother engine run due to the higher cetane number. Not really worth the extra 40 cent per gallon.
A fuel treatment will gain the same advantage, and maybe cheaper.When I lived in Texas, I found nothing wrong with the No.2 Diesel. Same stuff like ours

interesting post, Whitmore. Can you advise or even guesstimate how many BTU's are in diesel fuel spiked with WMO or 2 stroke oil? I guess it would depend on the mix ratio of the WMO, so lets say 20% just for simplicity. TIA

STATUS? BTW, why'd you change yer screename from WHITMORE TO WHIT???

Folks get to thinking Cetane is the way to go.Sure cetane will give better results than regular diesel.However a fuel containing more BTUs like ATF or WMO mix at 20% will make it fly.For one reason lubing of IP,and injectors reducing friction,two the higher BTUs.Ever used wmo to start a brush fire?Man it gets hot enough to burn green wood.

Actully Mercedes sells a BTU improver.True Europe has the best diesel fuel considering more than half the cars are diesel.

what is WMO? ATF will give more heat/power?