Jet A and A-1 are for all intensive purposes high quality kerosene. Very similar to #1 Diesel fuel
but do not have any additives to improve lubricity. Also cetane is uncontrolled so it very well may not meet minimum specifications.
What does that mean...It will run, you will burn more of it, create more heat, probably void any warranty you have on your engine, and increase wear on injectors and your injection pump
Jet A & Diesel No. 1 1.33
Diesel No. 2 3.20
Jet A and Diesel No. 1 tend towards lower viscosities. Lower lubricity is likely as the viscosity decreases. While this may not cause catastrophic instant damage, it could cause long-term wear of pumps
have additional specifications that aren't required of diesel fuels
. A couple examples of these are the requirement of testing for certain components and a volatility requirement. Some of the methods for testing also vary from one fuel
to the other. Basically, however, we have pointed out the biggest differences. If you need more detailed comparisons, please contact the ASTM society at their headquarters at 100 Barr Harbor Drive, West Conshohocken, Pennsylvania 19428. They could provide you with copies of the specifications. Their phone number is 610-832-9500.
Once again, we stress that you should contact the equipment manufacturers and ask what fuels are proper for use in the engines you are curious about. Also, you must make certain you are not breaking any legal regulations."
So the bottom line
is that although Jet-A may not cause immediate damage to a diesel engine and may allow the engine to run OK, its use may cause premature wear or fouling of the fuel system, and you may be breaking EPA regulations as well as not paying appropriate taxes. Outside the US, differences in viscosity still mean that the use of Jet-A for Diesel No. 1
may cause early wear of the fuel system. Kind of like running 10 weight oil in a car designed for 30 weight. So how much risk are you willing to take, because no engine manufacturer or fuel supplier will take part of the risk?
Diesel vs Jet Fuel
A New Diesel Fuel Additive Requirement
ASTM D-975, the ASTM standard for diesel fuel, is being modified to include a specification on diesel fuel lubricity. Lubricity is the fuel quality that prevents or minimizes wear in diesel fuel injection equipment. Diesel lubricity is largely provided by trace levels of naturally occurring polar compounds which form a protective layer on metal surfaces. Refinery hydrotreating processes which reduce the sulfur content of diesel blend components also remove these polar compounds. As a result, most of the diesels produced by refineries to meet January 1, 2006 ultra-low sulfur diesel (ULSD) sulfur specifications will not have adequate lubricating properties to meet the new ASTM lubricity specification.
Baker Petrolite is a leading provider of diesel lubricity improvers, fuel additives that restore the lubricating properties of severely hydrotreated diesel fuels. These additives have traditionally been added at the refineries producing the fuels.
In 2004 some major U.S. finished fuel common carrier pipeline companies announced that they would not allow the transport of diesel fuels already treated with lubricity improvers. This is due to their concerns about “trail back” of the lubricity additive into jet fuel tenders following the additized diesel, which are not allowed to contain these additives. As a result, most lubricity additive usage in the U.S. will take place at fuel terminals.