Biodiesel and the LB7

[dually2002]

The place that I buy diesel from specifies 5% to 20% biodiesel. Will having higher than 5% bio have negative effects on an LB7? Engine seems to run better with a bio/diesel mix.

[convert2diesel]

All good things seem to have a bad side to them. Bio-diesel is extremely susceptible to water absorption. The chemical name for bio-diesel is FAME or fatty acid methyl ester or FAEE or fatty acid ethyl ester. A major component in the processing of bio-diesel is either methanol or ethanol, both alcohols and as such will suck up any water that comes in contact with it, including air borne moisture.

In concentrations above 5%, the entrained water has some serious ill effects on any high pressure common rail fuel systems. Having said that, there are many advantages to bio-diesel, the primary one being at 5%, no more lubricity additives are required, even when mixed with ULSD. In concentrations above 5%, the cetane rating is better than straight ULSD as is the power output (more BTUs per gallon).

While commercial bio-diesel is getting more consistent and is being made better, in concentrations above 5%, the viscosity is higher. This may or may not have some effect on the fuel system.

If you have the intent of using this fuel, would suggest a very comprehensive filter/water separator be installed. At least it should be able to filter down to 2 microns and preferably have a dual stage water separator. There are a number of options available including Racor or John Kennedy has a complete system including a standalone fuel transfer pump. May seem pricey, but well below the cost of a set of injectors or high pressure pump.

Hope this helps.

Bill

[dually2002]

All good things seem to have a bad side to them. Bio-diesel is extremely susceptible to water absorption. The chemical name for bio-diesel is FAME or fatty acid methyl ester or FAEE or fatty acid ethyl ester. A major component in the processing of bio-diesel is either methanol or ethanol, both alcohols and as such will suck up any water that comes in contact with it, including air borne moisture.

In concentrations above 5%, the entrained water has some serious ill effects on any high pressure common rail fuel systems. Having said that, there are many advantages to bio-diesel, the primary one being at 5%, no more lubricity additives are required, even when mixed with ULSD. In concentrations above 5%, the cetane rating is better than straight ULSD as is the power output (more BTUs per gallon).

While commercial bio-diesel is getting more consistent and is being made better, in concentrations above 5%, the viscosity is higher. This may or may not have some effect on the fuel system.

If you have the intent of using this fuel, would suggest a very comprehensive filter/water separator be installed. At least it should be able to filter down to 2 microns and preferably have a dual stage water separator. There are a number of options available including Racor or John Kennedy has a complete system including a standalone fuel transfer pump. May seem pricey, but well below the cost of a set of injectors or high pressure pump.

Hope this helps.

Bill

Good information Thank you

[Hillbilly Jim]

I have been using 20% commercial soy Bio-diesel since 2001 in my Duramax . To date never had a problem and no injector problems. Dont drive much any more so maybe 3000 miles per year.
Took delivery on my truck on 12-08-2000.