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Tell Me the Facts About Biodiesel Fuel

We want to help you better understand biodiesel fuel.


What is Biodiesel Fuel?


Biodiesel is a renewable, oxygenated fuel.

It is made from agricultural and renewable resources, including soybeans or rapeseeds.


Biodiesel is 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. It does not contain petroleum-based diesel fuel --- but can be blended at any level with petroleum­ based diesel fuel.


If it is not blended with petroleum-based diesel fuel, such biodiesel is referred to as "B 100", which means it consists of 100% (pure) biodiesel.


Most common biodiesel is blended with conventional (petroleum-based) diesel fuel. The percentage of the blend can be identified by its name. The most common blends are "B 7" (consisting of 7% biodiesel and 93% conventional petroleum-based diesel fuel) and "B 20" (a blend of 20% biodiesel and 80% conventional diesel). Raw pressed vegetable oils are not considered to be biodiesel.


Advantages of Biodiesel Fuel


Let’s go through the advantages and disadvantages of biodiesel fuel.


Advantages include:

· Biodegradable and non-toxic.

· Safer than conventional diesel fuel due to its higher flashpoint.

· Less visible smoke.

· Lower amount of particulate matter.


Following the increased interest in the reduction of emissions and the reduction of the use of petroleum distillate based fuels; many governments and regulating bodies encourage the use of biodiesel.


Disadvantages of Biodiesel Fuel


Concentrations that are higher than 7% of biodiesel (higher than B 7) can have an adverse effect on the engine's performance, its integrity, and/ or durability. The risk of problems occurring in the engine increases, as the level of biodiesel blend increases. The following negative effects are exemplary and typical for the usage of high concentrated biodiesel blends.


Disadvantages include:

· Biodiesel typically creates deposits in the engines.

· Certain natural rubbers, nitride, and butyl rubbers will become harder and more brittle as degradation proceeds when used with biodiesel.

· Due to its natural characteristic, biodiesel will decrease the engine output by approximately 2% (in the case of B 20) comparing to conventional (petroleum-based) diesel fuel.

· Biodiesel can accelerate the oxidation of aluminum, brass, bronze, copper, and zinc.

· Biodiesel damages, and finally seeps through certain seals, gaskets, hoses, glues, and plastics.

· The fuel consumption ratio will increase by approximately 3% (in the case of B 20) compared to conventional diesel fuel.


Approved Yanmar Engines


All the following Yanmar engine series can be operated with biodiesel with concentrations up to B 20.


In case of using biodiesel fuel up to B 7 concentrations, no special preparations, etc. must be made, and the original operating conditions and service intervals, as stated in the operating manuals apply.


In case of running below indicated engines with biodiesel concentrations above B 8 up to B 20 --- the required operating conditions (see below Conditions for the operation with bio-diesel (B 8 through B 20)) must be observed.


Other than the following listed engines cannot be run with biodiesel:

· 3TNM74F

· 3TNV74F

· 3TNV80F


Approved Fuel

In the case of using biodiesel (only concentrations up to B 20), such fuel should comply with the recommended standards listed below.


However, raw pressed vegetable oils, are not considered to be biodiesel. They are not acceptable for use as fuel in any concentration in YANMAR engines.


1. EN14214 (European standard) and/or ASTM D- 6751 (American standard).


2. All applicable engines can be operated with biodiesel fuel up to B 20 (20% bio-fuel blend) as a maximum concentration.


(For your information: In Japan, the legally allowed maximum concentration for on-road applications is B 5.)


Conditions for the Operation with Biodiesel (B 8 through B 20)


When operating your applicable YANMAR engine with biodiesel blends concentrated above B 7, we seriously recommend observing the following operation, service, and maintenance conditions:


1. The original service interval of the services stated below, as indicated in the respective YANMAR engine standard operation manual, the application manual, and the service manual should be halved (please refer to your own manuals for each service interval):


· Drain interval of the fuel tank.

· Cleaning interval of the water separator.

· Replacement interval of engine oil filter, engine oil, and the fuel filter.


2. It is required to inspect, clean, and adjust the fuel injector every 1,000 operating hours.


3. Replacement of the following parts before using the recommended biodiesel:


· Fuel hose

· Fuel feed pump (diaphragm type)

· If not already installed, a water separator needs to be built-in

· O-ring of fuel filter

· O-ring of the water separator


Please refer to the list of exchange parts for details.


4. Please use only biodiesel fuel that is appropriate to the intended operating environment of the engines. This especially applies if the operating ambient temperature falls below 0 degrees centigrade.


5. Operation with biodiesel requires daily maintenance as follows:


· Please check the engine oil level daily. If the oil level rises above the oil level of the previous day, the engine oil needs to be immediately replaced.

· Please check the water level daily of the water separator. If the water level rises above the "max" indicator, an immediate drain of the water separator is required.


6. Biodiesel blends up to B 20 can only be used for a limited time of up to 3 months from the date of biodiesel manufacture. Therefore, biodiesel needs to be used at the latest within 2 months from the time of filling the tank or within 3 months from the time of production by the fuel supplier, whichever comes first.


7. Before long-term storage without operating the engine, the biodiesel needs to be drained out completely and the engine must be run for 5 hours with conventional diesel fuel as indicated in your operation manual.


If you need any further help or have any questions about biodiesel fuel, tractors, or anything else, please contact your dealer, local mechanic, or call us at 602-734-9944. Please ask about our current new and used tractor supply.



Team Tractor and Equipment - #1 Tractor Dealer in Arizona. We sell and service most major brands of tractors including Yanmar, Kubota, John Deere, TYM, Mahindra, Kioti, Case, New Holland, Massey Ferguson, Ford, Deutz, Case IH, Farmall, International Harvester, Branson Tractors, LS, Shibura, Claas Tractor, McCormick Tractors, Valtra, Solis, YTO, Montana, and Nortrac

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