With an increased interest in emissions and reducing the use of petroleum distillate-based fuels, some governments and regulating bodies are encouraging the use of bio fuels. Governmental incentives and/or environmental legislation requiring the use of bio fuels may have an impact on the sales and use of engines. As a result, Komatsu last week released its criteria and parameters for using biodiesel fuel in its engines.
The company’s recommendation is intended for those wishing to use biodiesel blends from B5 to B20. In the broad sense, the quality of available biodiesel blends remains inconsistent it is Komatsu’s recommendation that you follow the parameters as listed in this press release. Additionally, Komatsu suggests that you contact your local Komatsu representative to periodically report engine conditions and machine performance, when using biodiesel blends from B5 to B20.
· Biofuels – Fuels produced from renewable resources
· Biodiesel – A fuel comprised of methyl or ethyl ester-based oxygenates of long chain fatty acids derived from the transesterification of vegetable oils, animal fats and cooking oils. These fuels are commonly known as Fatty Acid Methyl Esters (FAME) or Fatty Acid Ethyl Esters (FAEE). Biodiesel properties are similar to those of diesel fuel, as opposed to gasoline or gaseous fuels, and thus are capable of being used in compression ignition engines.
· B100 – A fuel containing 100 percent biodiesel
· Biodiesel blend – A fuel comprised of a mixture of petrodiesel and B100 biodiesel. A biodiesel blend is typically designated by the percentage of biodiesel in the blend. For example: B5 is a fuel containing 95 percent petrodiesel and 5 percent B100 biodiesel.
· BQ-9000 – The National Biodiesel Accreditation program, which is called BQ-9000, is a cooperative and voluntary program for the accreditation of producers and marketers of biodiesel fuel. The program is a unique combination of the ASTM standard for biodiesel, ASTM D6751, and a quality systems program that includes storage, sampling, testing, blending, shipping, distribution and fuel management practices.
· Petrodiesel – Diesel fuel produced purely from petroleum. Petrodiesel can also be referred to as distillate diesel.
· Rapeseed Methyl Ester (RME) diesel – Biodiesel derived from rapeseed oil. RME diesel is the most common biodiesel used in Europe.
· Soy Methyl Ester (SME or SOME) diesel – Biodiesel derived from soybean oil. SME diesel is the most common biodiesel used in the United States.
Certification and standards
Komatsu certifies its engines based on using the prescribed Environmental Protection Agency and European Certification Fuels. Komatsu does not certify its engines on any other fuels. Therefore, it is the user’s responsibility to use the correct fuel as recommended by Komatsu and allowed by EPA or other local regulatory agencies. In the United States, EPA allows only registered fuels and fuel additives to be used in commerce. EPA has provided a website for additional alternative fuel information at:
The specifications for biodiesel are found under the ASTM D6751 Standard in North America and the EN14214 Standard in Europe. These specifications only define biodiesel (B100) used as the blended component with diesel fuel. These specifications do not cover the fuel blends that may be purchased by the end user. Despite the specifications and standards, the quality of available biodiesel remains inconsistent.
To use biodiesel, in Komatsu engines, it is imperative that the biodiesel fuel be of high quality and meet or exceed the specifications outlined in this report or engine damage will occur.
In order for the customer to successfully use biodiesel it is recommended that the fuel be of high quality and meet or exceed the specifications as outlined by Komatsu. It is also the responsibility of the customer/user to verify/obtain the proper local, regional or national exemptions required for the use of biodiesel in any emissions regulated Komatsu engine. If these items are disregarded engine damage may occur.
Requirements for using biodiesel fuel in Komatsu engines
Applications for diesel fuel and biodiesel fuel blends of up to B5, must meet the requirements of ASTM D975 D1 and D2 fuels. For biodiesel blends above B5 and up to B20, Komatsu is providing a specification found in Table 1. The specification in Table 1 has been developed by the Engine Manufacturers Association and is not an approved national or commercial fuel standard. All biodiesel fuel blends are to be comprised of petrodiesel meeting the ASTM D975 specification and B100 specification either ASTM D6751 or EN14214.
An acceptable biodiesel fuel blend of up to 20 percent volume concentrate (B20) biodiesel with 80 percent petrodiesel can be used for all Komatsu engines.
Customers must adhere to the following requirements of Komatsu when using biodiesel blends above B5 and up to B20. Komatsu requires the biodiesel fuel blend be purchased from a BQ-9000 certified marketer. The B100 biodiesel fuel used in the blend must be sourced from a BQ-9000 accredited producer. Certified marketers and producers can be found at the following website: http://www.bq-9000.org.
Under certain biodiesel operating conditions, fuel dilution of lubricating oil has been observed. Monitoring of fuel dilution can be accomplished by performing oil sampling. Fuel levels in lubricating oil must not exceed 5 percent.
In order to determine if the oil change interval needs to be modified, the end users are required to use oil sampling during the first six months of operation to monitor engine oil condition and fuel dilution of lubricating oil.
Fuel water separation
Biodiesel has a natural affinity to water and water leads to accelerated microbial growth. Storage tanks must be equipped with a fuel water separator to make sure that water is eliminated before entering the vehicle tank. In addition, equipment should be equipped with a water separator as well. It is recommended that the vehicle and storage tanks are kept full to reduce potential condensation in the tanks.
Due to the solvent nature of biodiesel, and the potential for “cleaning” of the vehicle fuel tank and lines when using biodiesel, new fuel filters must be installed when switching to biodiesel. Fuel filters will need to be replaced more often. Specifically, the first two fuel filter changes, after biodiesel introduction, will need to be changed at one half the standard intervals, i.e. if the standard interval is 500 hours then the filter will need to be changed at 250 hours.
Komatsu genuine fuel filters must be used for fuel filter changes.
Biodiesel fuel storage
Biodiesel fuel must be used within six months of its manufacture date. Long-term storage problems have occurred with biodiesel due to its poor oxidation stability. This poor oxidation stability is accelerated with increased ambient temperature. For this reason, Komatsu does not recommend using biodiesel for low use applications, such as standby power or seasonal applications. Your fuel supplier can recommend oxidation stability additives.
When using biodiesel for seasonal applications, the engine system must be purged before storage by running the engine on pure diesel fuel for o minimum of 30 minutes.
When storing biodiesel in bulk storage tanks the systems must be properly cleaned and maintained. Steps must be taken to minimize moisture and microbial growth in storage tanks. Users should consult thier fuel supplier for assistance in storing and handling biodiesel.
Avoid storing equipment with biodiesel blends in the fuel system for more than three months or fuel system damage can occur.
B100 biodiesel provides approximately 7 to 10-percent less energy per gallon of fuel when compared to conventional diesel fuels. Depending on the application, operating with B20 biodiesel blends can result in a slight decrease in fuel economy and power.
Engine material compatibility
Biodiesel may affect engine elastomers, therefore periodic checks of seals and hoses are required.
As previously mentioned, biodiesel has excellent cleaning properties. As mentioned earlier, fuel filters will need to be replaced and inspected more often. Specifically, the first two fuel filter changes after biodiesel introduction will need to be changed at one-half the standard intervals, i.e. if the standard interval is 500 hours, then the filter will need to be changed at 250 hours. When replacing fuel filters at any time, it is strongly recommended that the fuel filters be inspected for metal particles.
As previously mentioned, biodiesel properties change with ambient temperature change. In low ambient temperature, biodiesel will start turning waxy or gelling. Precautions must be taken when storing in low ambient temperatures by using a heated building or a heated storage tank. Additives can be used for low ambient operation.
The fuel system may require heated fuel lines, filters and tanks to avoid being plugged by biodiesel fuel solidifying in low ambient temperatures. A fuel heater is recommended for ambient temperatures below -5C (23F). Users should consult their fuel and additive supplier for assistance in attaining proper cloud point fuel.
Biodiesel fuel is an excellent medium for microbial growth. Microbes cause fuel system corrosion and premature filter plugging. The effectiveness of all commercially available conventional anti-microbial additives, when used in biodiesel, is not known. Users should consult their fuel and additive supplier for assistance.
Komatsu America is based in Rolling Meadows, Ill.