Maintaining your Diesel Fleet for Biodiesel

National Biodiesel OEM Technician Training Program

updated Feb 2010

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 (4.5 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

0100200300400500600700800

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 diesel No overdosing concerns

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

B20 vs. Diesel: In the shop With in-spec B20 and lower, the issues you

can expect to see in your shop are the same as you will see with petrodiesel

Except: Expect to see less lubricity related issues Expect to see less problems with after-

treatment Filter related issues may be related to cleaning

effect upon first use, or are likely normal diesel issues or out of spec or imposter biodiesel

Less black smoke from exhaust!

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

provided they are made with biodiesel meeting ASTM D 6751

More than 55% of U.S. manufacturers support B20 or higher blends in at least some of their equipment

Several more are completing testing and progressing toward support for B20 now that new ASTM standards for B6-B20 blends have been published (ASTM D7467)

Most are also recommending use of a BQ-9000 supplier

For the Latest OEM Updates… Visit:

http://www.biodiesel.org/resources/oemsfor a complete listing of OEM position statements on biodiesel, as well as the current U.S. Diesel Vehicles List

NBB Resourceswww.biodiesel.org

Biodiesel Training Toolkit

News Releases & Information Resources

Technical Library, Spec Sheets & Videos

OEM Warranty Positions on Biodiesel

U.S. Diesel Vehicle List

www.BiodieselAutomotive.org Dedicated to information exchange for biodiesel & diesel technicians

www.BQ-9000.org Listing of BQ-9000 Certified Companies

www.biotrucker.comListing of BioTrucker retail sites