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1. Biodiesel Fuel Information
Biodiesel is an oxygenated fuel made from renewable (agricultural) resources such as soybeans or rapeseeds. Biodiesel is a fuel comprised of long chain fatty acids (methyl or ethyl ester-based oxygenates) derived from the transesterification of vegetable oils, animal fats and cooking oils. Biodiesel does not contain petroleum-based diesel fuel, but it can be blended at any level with petroleum-based diesel fuel. In the case where biodiesel is not blended with petroleum-based diesel fuel, it is referred to as “B 100,” which consists of 100% pure biodiesel. However, most 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 5” (consisting of 5% biodiesel and 95% conventional diesel fuel) and “B 20” (consisting of 20% biodiesel and 80% conventional diesel fuel).

2. Advantages of Biodiesel: 
Due to increased interests in reducing emissions and petroleum distillate-based fuel usage, many governments encourage the use of biodiesel. 
a) Biodiesel produces less visible smoke and a lower amount of particulate matter (PM). 
b) Biodiesel is biodegradable and typically nontoxic. 
c) Biodiesel is considered safer than conventional diesel because of its higher flash point.

3. Disadvantages of Biodiesel: 
Concentrations greater than 5% biodiesel (>B5) may adversely affect engine performance and longevity. The risk of engine concerns increase as the blend of biodiesel increases. The following negative affects are typical with higher concentrations of biodiesel blends: 
a) Biodiesel can accelerate the oxidation of Aluminum, Brass, Bronze, Copper and Zinc. 
b) Biodiesel damages and finally seeps through certain seals, gaskets, hoses, glues and plastics. 
c) Certain natural rubbers, nitride and butyl rubbers will become inflexible, brittle and degrade when used with biodiesel. 
d) Biodiesel typically creates deposits in the engine. 
e) Biodiesel’s natural characteristics will decrease engine output by approximately 2% (in the case of B20) compared to conventional diesel fuel. 
f) Fuel consumption will increase by approximately 3% (in the case of B20) compared to conventional diesel fuel.

4. Approved Engines: 
When using biodiesel fuel blends up to B5 in Yanmar engines, no special preparations are required and the original operating conditions and service intervals (per the operation manual) apply. Only the Yanmar engine series listed below may operate with biodiesel fuel concentrations up to B20. However, when using any of the engines noted below with biodiesel fuel blends from B6 to B20, Yanmar recommends referring to theenhanced operating conditions listed under #6 (Operating Conditions with Biodiesel: B6 through B20) and the updated warranty information listed under #7 (Effects on Engine Warranty). 
Only the listed Yanmar engine series below may operate with biodiesel fuel concentrations up to B20: 

3TNM68, 3TNM72, 2TNV70, 3TNV70 and 3TNV76 in Tier 2 and Tier 4 configurations. 

3TNV82A, 3TNV84, 3TNV84T, 3TNV88, 4TNV84, 4TNV84T, 4TNV88, 4TNV94L, 4TNV98, and 4TNV98T in Tier 2, Tier 3 and Interim Tier 4 configurations.

4TNV106 and 4TNV106T in Tier 2 configurations.

4TNE92, 4TNE94L, and 4TNE98 for Forklift Applications in Tier 2 and Interim Tier 4 configurations.

5. Approved Fuel: 
When using biodiesel blends up to B20, said fuel must comply with the following standards. However, raw pressed vegetable oils are not considered biodiesel, and are unacceptable for use as fuel in any concentration in Yanmar engines. EN14214 (European standard) and/or ASTM D-6751 (American standard). All applicable engines may operate with biodiesel fuel up to a maximum B20 (20% biodiesel blend) concentration.

6. Operating Conditions with Biodiesel: B6 through B20: 
When operating the applicable Yanmar engine with biodiesel blends above B5, Yanmar strongly recommends observing the operation, service and maintenance conditions: 
a) The original service interval (per the operation manual) for the following should be halved: 

  • Replacement interval of the engine oil filter, engine oil and fuel filter. 
  • Cleaning interval of the water separator. 
  • Drain interval of the fuel tank.

b) It is required to inspect, clean and adjust the fuel injector after every 1000 operation hours. Page - 4 - of 8 
c) Replace the following components BEFORE using biodiesel fuel: (Please refer to Appendix B.) 

  • Fuel hose 
  • Fuel feed pump (diaphragm type) 
  • If not already installed, a water separator must be installed
  • O-ring of the fuel filter 
  • O-ring of the water separator

d) Yanmar does not recommend using biodiesel fuel in ambient temperatures below 0 degrees centigrade (32 degrees Fahrenheit). 
e) Biodiesel fuel usage requires the following DAILY maintenance: 

  1. Check the engine oil level. If the oil level rises above the oil level of the previous day, the engine oil must be replaced immediately. 
  2. Check the water level in the water separator. If the water level rises above the “max” indicator, immediately drain the water separator.

f) Biodiesel fuel blends up to B20 can only be used for a limited time of up to 3 months from the date of biodiesel fuel manufacture. Therefore, biodiesel must be used at least within 2 months from the time of filling the fuel tank or within 3 months from the time of production by the fuel supplier, whichever comes first. 
g) Before any long-term engine storage occurs, the biodiesel fuel must be completely drained from the engine and operated at least 5 hours with conventional diesel fuel as indicated in the operation manual.

7. Effects on Engine Warranty: 
Yanmar’s engine warranty protects against failures related to defects in material or factory workmanship. 
Damages, performance or service concerns determined by Yanmar to be caused by the use of biodiesel fuel not meeting the specifications outlined above are not considered to be defects in material or factory workmanship and are not covered under Yanmar’s engine warranty. The same applies to damages or other concerns induced by not complying with the recommended operating conditions of Yanmar engines with biodiesel fuel. 
The above is based on the latest technical expertise in terms of biodiesel fuel. Yanmar fully supports the use of environmentally beneficial alternative fuels. Our approved industrial engines are compatible with B5 to help encourage the greater use of renewable, domestically grown fuel. Yanmar continues its research in biodiesel fuel concentrations higher than 5% for more of our products. Yanmar is aware of the growing interest in higher concentrations of biodiesel fuel blends and supports this interest in renewable fuels.