Diesel to Biodiesel and back again?

[indigo_k]

One piece of information I've been trying to suss out and not having any luck with other online resources so I thought I'd check here and see if anyone knows for sure.

Everything I've read about Biodiesel (not waste veg-oil) is that it's 'essentially' interchangeable with regular diesel fuel, there's no conversion necessary, which is great.

BUT, what I want to know is, can you fill up with either Diesel or Bio depending on availability? Say I'm down to my last few gallons of Bio, and there isn't another Bio station nearby - can I just fill it with regular Diesel and keep driving? Like, is there a problem mixing them in the same tank, or do you need to somehow run the tank dry before switching from one to the other?

It seems like you should be able to if they're truly interchangeable, but I can't find any confirmation on it.

[Brad_SwiftFur]

I've driven interchangeably on both. Biodiesel is readily available in the midwestern states but not so much in, say, south Florida. Truckers mix and match whatever is available at whatever truck stops they use.

[Native]

It is my understanding that the base oil and method used for brewing the biodiesel can have an effect on the energy available in the biodeisel,. However, the effect is not enough to be concerned about for most applications. Besides, one can not tell what was used to make the biodiesel sold at the pump. Note: I have no personal experience with biodiesel unless it is already at the pump.

[indigo_k]

Originally Posted by Brad_SwiftFur

I've driven interchangeably on both. Biodiesel is readily available in the midwestern states but not so much in, say, south Florida. Truckers mix and match whatever is available at whatever truck stops they use.

Thanks, that's what I was hoping! No reason not to at least aim for Biodiesel stations then!

[TheatricalKate]

That's my understanding too. Mix as needed.

I am finding www.biodiesel.org to be a great resource finding biodiesel filling stations. I'll be driving my newly purchased bus up from NM shortly on biodiesel!
Kate.

[ben_marko]

Biodiesel is completely soluble with petroleum diesel. I first started using BD by just dumping it into my fuel tank. Ratios were...inconsistent. Never had a problem.

[ben_marko]

Originally Posted by Native

It is my understanding that the base oil and method used for brewing the biodiesel can have an effect on the energy available in the biodeisel,. However, the effect is not enough to be concerned about for most applications. Besides, one can not tell what was used to make the biodiesel sold at the pump. Note: I have no personal experience with biodiesel unless it is already at the pump.

Bio has a lower cetane value than petro diesel. But it's not much.

[CHEESE_WAGON]

Originally Posted by Brad_SwiftFur

I've driven interchangeably on both. Biodiesel is readily available in the midwestern states but not so much in, say, south Florida. Truckers mix and match whatever is available at whatever truck stops they use.

Interesting. Not second-guessing you, of course -- But most, if not all, carriers I drove for instructed me to never fuel with bio. I drove for this one crazy old coot that forbid fueling in MN in winter, not sure what the h-e-double-hockey-sticks THAT was about.

My understanding through commercials for bio is that it is largely made from algae, something I understand to have been a big problem with marine diesels, and I have heard some trucks running it full-time have experienced fuel system problems. Of course, in regard to the biodiesel, last time I drove commercially was late 2017, so perhaps things have changed?

I'm thinking per your statement that perhaps it hinges on the percentage of bio. I've seen B20 on some pumps, which I understand some setups are not equipped to deal with. I got yelled at once for trying to fuel B20 in Michigan. Maybe that's the rub... *shrugs*

[ben_marko]

The amount doesn't matter. Bio is completely soluble with dino diesel. The MN guy was probably worried about viscosity in the cold. It makes sense if you're running anything above B60-ish (my best guess).

[ajcantarella]

You can mix biofuel and petroleum based. all new diesels are required to run on bio 20
20% bio 80% petroleum. So as you can see it is quite common to mix. Also as ambient temps drop, you may want to increase petroleum %.

[CHEESE_WAGON]

I don't recommend biodiesel. It tends to clog filters in cold weather. I was instructed at every trucking carrier I drove for not to use it in their trucks.

[s2mikon]

Beware of bio diesel if you have an older vehicle. Bio diesel has a higher solvent action than dino diesel and can be detrimental to seals and hoses with natural rubber or nitrile compounds. Some of these injection pumps can be quite expensive to repair. Also if the front seal fails in the injection or transfer pump, diesel will leak into the engine oil and cause extensive engine damage if not caught soon enough. Some of the low emission diesel tends to do the same. This solvent action also causes the thin wax film that coats the fuel tanks to drop and plug the fuel filters. Be sure to carry extra filters. Newer engines are designed to run on bio but older engines are not. If you have the original manuals for most older engine fuel systems most of what is sold as dino diesel today fails in one or more category. This has led to the rise in additives for diesel fuel. Some work some don't. It's just like gasoline, today's gasoline is is incompatible with older engines. It will run but not like it should. Gasohol and small engines is a disaster. So be careful you don't want to deplete your bank account to reduce exhaust emissions a few percent.

[Night Roller]

Been driving truck for 20 years (petroleum tankers), in MN. When MN dictated 10% bio we had many problems with clogged fuel filters. Luckily I had been running my VW diesels for a few years on straight WVO for a few years already, so I knew what to expect.
WVO or Bio will clean out your oil & fuel lines in one way or another, this all ends up in your filters (Fuel & Oil). You need to change your filters, especially Fuel filter in probably the first 2000 miles, again around 6-7000, & probably again around 15-20k miles.
If you keep running bio in your engine, even a 10-20% you shouldn't have to worry about your filter plugging up. There's a reason they call it "Dirty Piesel".

[ben_marko]

Read through this thread and I know it's old but hopefully someone reads this.


s2mikon is right, you need to make sure that seals and hoses are upgraded for older diesels. Most of the time it's just the fuel lines that need upgrading. Don't listen to truckers who claim it clogs up your fuel system, it actually does just the opposite.



You will also (no one's mentioned this) run as little as 2% bio in your tank. If it's your first time putting it in the tank, then keep spare fuel filters and the tools on hand to change them out if possible. Biodiesel will clean out a virgin fuel system in about 30 days on average.



I was able to change out both the fuel filters on my Ford 6.0L in about 15 minutes once I noticed the truck was starting to chug-a-chug-chug due to clogged filters. Both filters were only 4 months old, but the one in the engine compartment was dark, dark gray and smelled nasty. After I changed them out it was fine.

[TheatricalKate]

Read & appreciated!