Bio-diesel / Is it a good or bad thing for the engine ?

[T18skyguy]

I went to fill with diesel at my favorite Chevron station, and I noticed the diesel pump said something like S15. I had no choice at the time, so I only put in 10 gallons, cause I knew I could get better stuff later. A guy at the station remarked that it was ****, and bad for the engine and injectors. I get the environmental part, anybody know the facts about it's effects on the engine?

[naturist]

You are going to get a LOT of contradictory information and advice here asking that question. I can only tell you that most of what is/will be said is tainted by unsubstantiated opinion.

But I will tell you facts. I have had three diesels, two that were supposed to only use no more than 5% biodiesel, and the third no more than 7%. All three have been run at higher concentrations without incident. One of the 5%ers has 180,000 miles, of which around 100,000 miles was more or less continuously at B20 to B50, with occasional brief periods on B100. At around 125,000 miles the injection pump started leaking and had to be replaced. It should be noted that this seems to have happened to others of its type that have never run biodiesel, so I'm not sure it had anything to do with biodiesel.

The second, another 5%er, ran for around 50,000 miles on B20-B50 without incident. At 150,000 miles, an overheating incident while towing caused a blown head gasket and cracked head, which was replaced. At 200,000 miles, the last being with no biodiesel, the rebuilt head with new valves, dropped an exhaust valve killing the engine. Clearly the biodiesel had nothing to do with the dropped valve.

The third, and newest of them now has 110,000 miles, and though officially limited to B7, has seen an occasional tank of up to B20, without skipping a beat. This vehicle is the only one of the three with a DPF.

There are strongly opinionated people who will insist that a single tank of 5% biodiesel is the reason their radio no longer works. I know this, because I've met them.

Frankly, my own personal experimentation has resulted in my own opinion that use of biodiesel has no untoward consequences for engines, enough so that I don't worry about it at all.

[wq93]

Bio helps provide some of the lubricity lost with the switch to ULSD years ago. I have been using it in my diesel pickups for years without trouble and my circa 1995 Deere utility tractor uses it also with no problem. My soon to be delivered 40KW standby generator will also be running a bio blend.

Your biggest issue will be it has higher cloud and gel points than non-bio and vehicles designed for higher concentrations will generally have a larger capacity fuel heater at the filter. Bio diesel is a little better solvent than straight diesel and an older fuel system first introduced to bio will likely need a filter change fairly soon for the first cycle.

You have probably run bio before without knowing it because it has been prevalent in most of the market for over a decade.

I hate "farmer gas" ethanol fuel but I am fine with bio diesel (which also makes far more sense economically and environmentally than the ethanol laced garbage fuel).

[thomas201]

Bio has fewer BTU's per gallon, so you will take a small MPG hit. I worked for a rendering plant as the plant manager for about 5 years. We could not make the math work for producing our own biodiesel. It was worth too much as chicken feed. However, we were happy to sell it to others.

[4x4ord]

We buy our fuel by the super b load (63000 litres at a time) and purchase based on price.... I think we experienced one failed injector in the last 20 years.

[Lynnmor]

Be sure to check your owners manual for motor oil requirements if you are using bio-diesel. For example, Ford requires 5-40 or 15-40 instead of the normal 10-30 when using bio.

[lenr]

My engine is rated for B20 so B15 or less doesn't scare me. In the infamous diesel fuel lubricity study a few years ago, B2 created better lubricity than any additive on the market. Supposedly bio burns with less soot, but at low levels it's probably not noticeable. I'm WAY more concerned about getting fresh diesel than avoiding bio-diesel.

[twodownzero]

I buy it every chance I get. It's better for the injectors. Change your fuel filter regularly and it will be fine.

[Groover]

I know that some engines are rated for it some are not. I tend to stick with what the manufacturer recommends for the engine I have.

My guess is that some bio fuels are processed better and kept dryer than others. The good ones are probably fine in any engine and the engines rated for biofuel are more tolerant due to extra equipment and/or tuning. It may also depend on how long you leave it in the tank and the climate in your area if it is hydroscopic.

I have a friend that went in big on biodiesel for about a year then decided that he could buy a lot of diesel fuel for what the new Cummins cost him. Your results may vary.

[Ductape]

Labman7 wrote:
Ask on a diesel forum. It's all they sell in many Midwest states. Works great , keeps system clean, adds lubrication. Have over 115,000 on my 2015 Duramax using it, no issues.

+1 most of what you'll get here is opinion and hyperbole.

People who drive diesels for a living don't go out of their way to chase a particular blend. Save those worries for adult beverage choices. 😉

[Labman7]

Ask on a diesel forum. It's all they sell in many Midwest states. Works great , keeps system clean, adds lubrication. Have over 115,000 on my 2015 Duramax using it, no issues.

[Ski_Pro_3]

I'm pretty sure my 2006 Dodge RAM diesel owner manual says not to use it. Even 5% stuff.

[Turtle_n_Peeps]

Bio D can and does retain water. It is hydroscopic. It will hide in the fuel itself.

Todays new fuel systems do not put up with ANY water. The pressures they run now days will kill the pump or injectors in a heart beat.

I do not like the stuff nor do I use it when there is straight #2 for sale.

Todays modern fuel systems cost 15 grand+ to replace. "Do you feel lucky? Well do ya?"