Maintaining your Diesel Fleet for Biodiesel

National Biodiesel OEM Technician Training Program

Today’s Topics

Biodiesel Definition Key Properties of Biodiesel Fuel System, Air Intake, &

Lubrication Starting, Charging, Cooling, &

Vacuum systems Exhaust & Emissions Controls Resources

Biodiesel Defined Biodiesel, n. -- a fuel comprised of

mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, meeting ASTM D 6751, designated B100.

Biodiesel Blend, n. -- a blend of biodiesel fuel with petroleum-based diesel fuel designated BXX, where XX is the volume percent of biodiesel.• This tight definition was needed in order to secure

vehicle, engine and fuel injection equipment company support for biodiesel, as well as to secure ASTM specs

Biodiesel (B100) Attributes

High Cetane (avg. over 50) Ultra Low Sulfur (avg. ~ 2 ppm) High Lubricity, even in blends as low as 1-2% High Energy Balance (3.5 to 1) Renewable, Sustainable, Domestically Produced Increases overall fuel production capacity in

USA Reduces HC, PM, CO in existing diesel engines

Enhanced Lubricity

Ultra-low Sulfur Diesel

0

100

200

300

400

500

600

700

800

0.0 1.0 2.0 3.0 4.0 5.0

Biodiesel Blend (%)

HFRR WSD (micron)

Equipment benefits Superior lubricity B2 has up to 66%

more lubricity than #2 Diesel

EPA required sulfur reduction in 2006

No overdosing concerns vs. other lubricity additives

Cold Weather Performance Pure biodiesel does freeze faster than most

petrodiesel Your B20 supplier should provide blends of B20

that will not cause any cold flow issues in the winter Exactly the same way they do with #2 diesel fuel

There are a variety of tools at the disposal of distributors to improve the cold flow operability of #2 petrodiesel and biodiesel blends Blending with #1, cold flow additives, etc.

B20 has been used successfully in climates below -20ºF

Biodiesel Fuel Stability

The biodiesel specification contains parameters for insuring adequate fuel stability for normal applications

The shelf life of biodiesel blends is recommended by NBB as 6 months

Stability additives available on the open market

Solvency Effect

B20 & Under Monitor filters, less than 2% need to be

changed Mild cleaning effect Storage tanks may need to be cleaned, or

keep extra filters on hand at start up Housekeeping protocols for generic diesel

equally important prior to blending

Fuel System Material compatibility is key for higher blends Repair Fuel leaks to prevent impact to other systems! From the fuel sending unit in tank to injectors-primary & secondary fuel filters-Fuel lines (sending & return)-High pressure or low pressure injectors- o-rings-transfer & injection pumps

Lubrication System Change oil as recommended by

Engine manufacturer Use OEM recommended engine oil API, CI rating Regular oil analysis maintenance

program Inspect dipstick for biodiesel smell

Lube Oil Contamination Current ongoing research, SAE CI Engine

Performance with Alternative Fuels, 2008 A concern of engine manufacturers. Same mechanism for the oil dilution for

heavier fractions of diesel fuel as for biodiesel. Due to high boiling point of biodiesel, the fuel

is slower to vaporize after injection into the cylinder.

Remaining compounds will be deposited on the cylinder wall where they can be pulled into the crankcase by the normal scraping action of the piston's oil control rings.

Air Filtration In a diesel engine, the amount of air

remains constant while fuel amount is varied for speed and power control

Lean mixture at idle ( 80:1 ) Rich mixture under load (20:1) Mass Air Flow (MAF) sensor VW TDI EGR/ Intake design Diesels thrive on air, lots of it, any air

restriction will cause performance problems

Starting & Charging System Properly charged battery Operating Starter or Alternator Fouled glow plugs can cause hard

starting Glow plugs factory recalls Dual Battery system

Vacuum System Older diesel maintenance issue Leaky & Inoperative vacuum system

can affect:Brakes, Fuel shutoff, & transmissions

Cooling System Cooling system helps your engine warm up

& cool down Operating at optimum temperature helpsfuel economy & engine life

Cooling system hoses are not always biodiesel compatible, repair fuel leaks immediately to prevent damage to other systems

Exhaust & Emissions Controls

EGR: exhaust gas recirculation Catalytic converters Diesel Particulate filters Diesel Oxidation Catalyst SCR: selective catalyst reduction (Urea) Emissions regulations dictating changing

engine and fuel injection design

Are you Smoking? Black smoke: injectors, air inlet restriction, engine

timing, internal engine timing, injection pump failure

Blue Smoke: insufficient fuel, contaminated fuel,High or low oil consumption, air in the fuel

White smoke: bad glow plugs, plugged return fuel line, insufficient fuel supply, low compression, air in fuel, injector or pump problem, engine timing

White smoke can be normal in cold weather before engine warms

Miscellaneous NOx Emissions see:NREL’s “NOx solutions for Biodiesel” Cold weather Operation Timing belts & chains- replace at

recommended intervals Educate your fellow technicians Bosch & Stanadyne & FIE/OEM

statement

OEM Warranty Statements and Biodiesel All major U.S. OEMs support B5 and lower blends,

provided they are made with biodiesel meeting ASTM D 6751, the existing ASTM International standard for pure biodiesel (B100)

Many are progressing toward support for B20due to recent approval of a new ASTM standard for B20 blends

Use of blends higher than B5 will not necessarily void existing warranties

For a complete listing of OEM position statements on biodiesel, visit: http://www.biodiesel.org/resources/fuelfactsheets/

standards_and_warranties.shtm

NBB Resources

•www.biodiesel.org• Technical Library

• Biodiesel Bulletin

• Educational Videos Available

• Informational Resources

• Technical Resources

• On-line Database & Spec Sheets

•www.BQ-9000.org • Biodiesel Quality Certification Program for Accredited Producers and Certified Marketers