B5 from B20

esteeze

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Hopefully, this question hasn't been asked/answered elsewhere...

Is it generally a good idea to take B20 from a retail pump, and "blend" it with dino diesel to arrive at the VW recommended B5 concentration limit?

B20 is available locally for me now, and I'd like to give it a shot; but, I don't want to cause more trouble that its worth.

I'm just wondering if it's a good idea to maybe blend it in the gas tank (add about 1/2 gallon of B20 before filling up with about 10 gallons of dino diesel should do it... in theory anyway).

Edit: I realize my calculation mistake as I click "save"... actually, I think the proportions would be about 2.5 gallons of B20 with 7.5 gallons of dino diesel - for total of 10 gallons of B5.
 
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copperz

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eveyone is going to say fill up with the b20 and not worry about it. But yes, you can add it to the half thank of gas and have about 5% bio .
 

esteeze

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yeah, from what I've read, I've gathered that B20 would probably be fine as long as it's from a reputable source (ASTM certified, etc). This would be from a heavily frequented BP station, so it's probably fine.

I figured that "cutting" the B20 with enough dino diesel to approach a B5 concentration would at least give me a level of initial comfort.
 

06JettaTDIdsg

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esteeze said:
yeah, from what I've read, I've gathered that B20 would probably be fine as long as it's from a reputable source (ASTM certified, etc). This would be from a heavily frequented BP station, so it's probably fine.

I figured that "cutting" the B20 with enough dino diesel to approach a B5 concentration would at least give me a level of initial comfort.
Honestly, I went from straight dino to B20 and could tell no difference at all, except there was less smoke on hard acceleration. I did this with about 37k miles on my '06. I don't think you will have any issues at all.
 

Drivbiwire

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By the book, B5 is the official limit.

B20 in a 2006 more than likely won't cause any issues since you do not have a DPF or LNT catalyst and only have an oxidizing catalyst.

If you cut the B20, shoot for at least B3 ratios for maximum lubricity improvement to ULSD regardless of how poor the lubricity was from the pump.

More than B5 does not provide much further improvement in terms of lubricity and system protection.

Depending on your fuel feedstock the oxidation stability comes into question anytime you go above B5, most retail suppliers (I would assume) get the fuel from reputable suppliers which take measures to insure consistent end quality to the consumer.

DB
 

Diesel Addict

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Don't blend in your tank. You may get water separation. Use B20 and don't worry about it. If you're one of the paranoid people who worry to death about warranty, use pre-blended B5 or just plain diesel.
 

soberups

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You can blend in your tank with no issues, but it probably wont be worth the hassle....you can just run the b20 and not worry about it. I have the same car you do and I have run nothing but B99 in the summer and b20-b50 in the winter with ZERO problems for over a year now. I have 14,000 miles on the car, I pulled my fuel filter for inspection at 10K and it was clean as a whistle. I have never put anything BUT biodiesel in my car since the day I bought it new.
 

soberups

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Diesel Addict said:
Don't blend in your tank. You may get water separation. Use B20 and don't worry about it. If you're one of the paranoid people who worry to death about warranty, use pre-blended B5 or just plain diesel.
If we follow this logic...then once you have fueled up with b20 you can never use D2 again? That makes no sense at all. Think about it...if you filled your tank with b20 and were down to 1/4 of a tank and then filled up again with D2, you would have....b5! What is wrong with that? D2 and biodiesel are completely interchangeable and can be blended to any percentage desired with no ill effects.
 

esteeze

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06JettaTDIdsg said:
Honestly, I went from straight dino to B20 and could tell no difference at all, except there was less smoke on hard acceleration. I did this with about 37k miles on my '06. I don't think you will have any issues at all.
How many B20 miles have you racked up so far?
 

esteeze

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Diesel Addict said:
No magic involved. It's called draining. At least that's what the supplier or manufacturer should be doing.
I don't think I understand why H20 would necessarily separate from the BioD component of the B20 fuel if it is further diluted with petroD. Can you further explain?

Wouldn't it even be negligible in the volumes we're talking about (10 gal of combined volume B5 has about 1/2 gal of BioD... doesn't seem like much H20 could be liberated from that).

Never thought I'd have a practical use for my organic chemistry classes...
:)
 

naturist

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in talking with a guy whose business is rebuilding diesel injection systems (yes, he's the local Bosch guy) water in your diesel is an epidemic these days, and has been for a couple years.

Water is not very soluble in either petro or bio diesel. But it is marginally more so in bio than in petro. But in either case, it is not the water in solution that causes problems, it is the entrained/emulsified water that causes trouble.

This is the very water your fuel filter/water separator is supposed to catch.

So I don 't buy the notion that mixing b20 to b5 in your fuel tank is going to have any significant effect on water separation. At the same time, although the two are quite miscible, mixing in this fashion does not provide a good mechanical mix. Because there is a small density difference, there is also a tendency for the two to not mix thoroughly on their own. You tend to get a stratification in the tank similar to what would happen if you poured warm water onto the top of a tank of cold water. To minimize the consequences, you will want to pour the b20 in first, then add the petro.

Then be sure to mix thoroughly by turning the car upside down and back at least a dozen times while shaking vigorously.
 
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06JettaTDIdsg

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esteeze said:
How many B20 miles have you racked up so far?
we just started running it so probably 4-5 tanks (2500 miles or so). The car is just about due for it's 40k service so I am waiting till then to change the fuel filter. Before running B20 we ran regular old dino diesel.
 

esteeze

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naturist said:
Then be sure to mix thoroughly by turning the car upside down and back at least a dozen times while shaking vigorously.

LOL

I'm thinking I might just alternate fillups of B20/petroD, filling up alternately with one or the other once my tank is half-full (or half-empty, depending upon the kind of day I'm having at the time).
 

Ron 33

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LOL.......I've been running B20 off & on for a couple of years. Switching between dino & bio is not a problem. The reason I go back and forth is the availability of bio at home is zero, but I can get it near where I work (40 miles from home). Bio is not always available on road trips either.
I have had zero water problems, always changed my own filters. They always checked good, no water. I have 198,442 miles on this puppy and expect to hit 200,000 shortly with some mix of bio and dino shaken not stirred in the tank.
Water can be a problem with a bad supplier, but I have not had that problem.
 

Diesel Addict

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The water separation issue has to do with different water solubilities as naturist hinted at. Biodiesel tends to be saturated with water after it's washed of methanol and ready to use. Petro-diesel can't absorb as much water so when you mix the two, the water solubility of the mix will be lower than that of pure bio, resulting in some of the water dropping out. This is mainly an issue when blending B100 with petro-diesel in your tank. Mixing B20 with petro-diesel won't be as big of a problem, but it might still result in small quantities of water dropping out. IMO, even a drop of water in the fuel system is bad, so the more you can avoid it the better. Intentionally diluting B20 to B5 just to meet some arbitrary number set out by VW makes absolutely no sense in my view. Of course your view may differ.
 

esteeze

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Diesel Addict said:
The water separation issue has to do with different water solubilities as naturist hinted at. Biodiesel tends to be saturated with water after it's washed of methanol and ready to use. Petro-diesel can't absorb as much water so when you mix the two, the water solubility of the mix will be lower than that of pure bio, resulting in some of the water dropping out. This is mainly an issue when blending B100 with petro-diesel in your tank. Mixing B20 with petro-diesel won't be as big of a problem, but it might still result in small quantities of water dropping out. IMO, even a drop of water in the fuel system is bad, so the more you can avoid it the better. Intentionally diluting B20 to B5 just to meet some arbitrary number set out by VW makes absolutely no sense in my view. Of course your view may differ.
That makes sense.

I particularly agree with: "Intentionally diluting B20 to B5 just to meet some arbitrary number set out by VW makes absolutely no sense in my view."

From a practical standpoint of the risks involved with being non-compliant with VW's guidelines, I don't see where there can be a whole lot of difference between B20 and B5. I'll probably just alternate fillups of B20 / petroD; that's a lot more practical anyway than mixing the same tankful with fuel from two different fueling stops (i.e., fillup half-way with petroD, then drive across town and fill up the rest of the way with BioD... that's kind of silly).
 

ALAND

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esteeze said:
LOL

I'm thinking I might just alternate fillups of B20/petroD, filling up alternately with one or the other once my tank is half-full (or half-empty, depending upon the kind of day I'm having at the time).
That got me thinking about alternating fillups in general. This strategy never gets you to B5: after a couple of tanks, depending on your starting concentration, you end up alternating between B6 and B13. Alternating B100 and petro means your concentration swings wildly between B66 and B33. That can't be good. Seems like if you're gonna blend, you can do it most consistently if you fill your tank up with your desired combination. Then the concentration is only out of whack as you drive between the Bx pump and the dino pump.
By the way, my car has been on a straight diet of B20 or B100 since I got it with 24k on the clock. Over 52k now and the only problem is that my key fob stopped working...
 
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HotRod

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Get several 5 gallon containers of B100 and blend as needed. B5 as a maximum number is ridiculous. These cars run perfectly on B20, just a little smoother and less smoke. Some of you guys act like B5.5 is going to make the car stop running. I have 37,000 miles of B100 and two fuel filter changes. One filter changed after 14,000 miles of use and another clogged by bad quality fuel.
 

esteeze

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HotRod said:
Get several 5 gallon containers of B100 and blend as needed. B5 as a maximum number is ridiculous. These cars run perfectly on B20, just a little smoother and less smoke. Some of you guys act like B5.5 is going to make the car stop running. I have 37,000 miles of B100 and two fuel filter changes. One filter changed after 14,000 miles of use and another clogged by bad quality fuel.
Yeah, that probably would be a consistent way to blend; however, I'm not crazy about the idea of storing a bunch of containers of fuel at my home.

I'm hearing from enough people that B20 is probably gonna be fine. I'll give it a shot.


PS: Thanks for everyone's input... it has been helpful.
 
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soberups

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esteeze said:
Yeah, that probably would be a consistent way to blend; however, I'm not crazy about the idea of storing a bunch of containers of fuel at my home.

I'm hearing from enough people that B20 is probably gonna be fine. I'll give it a shot.


PS: Thanks for everyone's input... it has been helpful.
FYI, B100 biodiesel is quite safe to store in your garage, shed or basement. It has a far higher flash point than gasoline, is not considered explosive, and is non toxic. There is no real difference in volatilty betwween biodiesel and, say, cooking oil or motor oil.
 

fruitcakesa

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I went through the same wanna, don't wanna use BD worries. So I worked up slowly from B20 to about B66 through last summer then cut back down to < B20 for the cold Vermont winter. This spring once temps were consistently above 60* F I started with B100 and as of today have had no issues whatever. The car had 34K dino diesel miles when I bought it and have now cracked 80k with about 20k miles run on BD. BTW, I am a BD homebrewer.
 

Dooglas

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B20 is a completely satisfactory year round fuel. If it is available locally from a reputable supplier, I suggest you just use it and forget about mixing. That is what I do and 24,000 later my TDI is running great.
 

OkiTdi

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Blending in the tank isn't a great idea. Biodiesel does not mix well when splash blended. If you really want B5, you need to blend in a separate vessel with some sort of agitation to promote the mixing.

OkiTDI
 

esteeze

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I went ahead and filled up with B20 from the one retailer in my area (about 10 miles away). It's actually less expensive than the D2 I filled up with last week (2.67 vs 2.79); the B20 is in a different, less urban county, and lower taxes/overhead there may be part of the difference.

So far, so good; I've driven about 50 miles on the B20. The retailer had a lot of documentation on BioD, and they had a biodiesel.org sticker on the pump; so it gave me a certain level of comfort buying it from them.
 

esteeze

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soberups said:
FYI, B100 biodiesel is quite safe to store in your garage, shed or basement. It has a far higher flash point than gasoline, is not considered explosive, and is non toxic. There is no real difference in volatilty betwween biodiesel and, say, cooking oil or motor oil.
Yeah, I appreciate that BioD would be safer than some other fuels; I just don't want to get into the business of storing any kind of fuels at home. I would probably be more open to it if I lived in more of a rural area.
 

Diesel Addict

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esteeze said:
I went ahead and filled up with B20 from the one retailer in my area (about 10 miles away). It's actually less expensive than the D2 I filled up with last week (2.67 vs 2.79); the B20 is in a different, less urban county, and lower taxes/overhead there may be part of the difference.

So far, so good; I've driven about 50 miles on the B20. The retailer had a lot of documentation on BioD, and they had a biodiesel.org sticker on the pump; so it gave me a certain level of comfort buying it from them.
I'm jelous. Here in my city we only have B5 that's 20c more expensive per gallon than D2 and you have to use their cardlock and pay by check every month, and there's another place about 50 miles away that sells B100 for about 50c more per gallon than D2. If I had a local source of B20 that's good quality and about the same price as D2 or cheaper, I'd be all over it.:(
 

soberups

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OkiTdi said:
Blending in the tank isn't a great idea. Biodiesel does not mix well when splash blended. If you really want B5, you need to blend in a separate vessel with some sort of agitation to promote the mixing.

OkiTDI
He is talking about turning b20 into b5. What would be the harm in having 1/4 tank of b20 in your car and then filling it up with D2? You would wind up with an approx b5 blend. How would quality b20, which is already a blend to begin with, fail to mix properly with D2 in a fuel tank?
 

Ron 33

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Dino & Bio which both meet their respective ASTM Standard, are allowed to have a maximum of .05% water and sediment. Mixing the two should be no problem.
 
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