JSW seems to be running a lot smoother on B5?

masterflex164

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I've found a station that pumps B5 about an hour from me and I've been taking trips to that area, so I've been running on this B5 for the last 2 or so tanks, the engine seems to be much much smoother. Less rattle, less noise, and more power. MPG seems to never dip under 40 on the highway according to the MFD, but when I use local Mobil or Sunoco "premium" diesel, I'm never acheiving that kind of mileage
Is this a fluke or is B5 just that much better?
 

numl0ck

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The added lubricity of the bio is making your engine run quieter and smoother. I have access to B5 and usually run it, but when I don't the engine is a bit louder and has more "clatter". The B5 also reduces wear on the HPFP.

Run B5 when you can, 'tis very good for your car. :)
 

Fixmy59bug

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I made the same notation when I first ran B5. I thought I was going deaf because I could barely hear my engine. But then I compared it to another 2009 TDI and sure enough, mine was quieter.
 

scirocco*joe

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Has anyone tried mixing fuels? I only have B20 in my area and was thinking of mixing 3 gallons of B20 with every full fill up. I figure so long as B20 is less than 25% of the fill, I should be good as far as meeting VW's recommendation maximum of B5. However, i have no idea if it is safe to mix in the tank.

?
 

Fixmy59bug

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Yeah, It's safe. That's essentially how a lot of people add bio diesel to their tank.

I dump two 60oz bottles full of B100 into the tank, then top off with D2 since I now choose to run B7.
 
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adrienne

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Same here, but two 60z bottles seems like more than 5% - how big is that Jetta tank?! Just curious. For my '10 JSW, I dump in two 43oz (roughly 84oz total) bottles of B100 and then fill ~13.5 gal of D2. When I'm using B99 instead, I just make sure I refill sooner, like at around 13 gallons. Engine is happier, more efficient and quieter.
 

Fixmy59bug

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Nope, I carefully did the math when I started usng Bio to make sure I didn't go over what Vw allowed so as to avoid warranty issues.

The Jetta tank is 14.5 gallons. 1 gallon is 128 ozs, that equals 1856 ozs.

So B1 would be 18.56 ozs of B100
B2 = 37.12 ozs
B5 = 92.8 ozs (Your 84 ozs is equal to approx B4.5)
B7 = 129.92 ozs (B6.5 = 120.64)
 
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sgoldste01

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I've read many people on this forum say that they add 1 quart of B100 per tankful. One quart = 32 ounces.

So according to the above calculations, 1 qt of B100 would provide slightly less than B2.

Of course, we generally don't fill our tanks when they're completely empty. I generally fill up when I hit 500 miles on the odometer, which means I probably have approximately 2 - 3 gallons remaining in the tank. Over time, adding 1 qt of B100 to the tank would yield a higher value than B2, since the 2 - 3 gallons still in the tank already has some biodiesel in it. Refueling with even more fuel remaining in the tank would accelerate this effect.
 

WVU TDI

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Nope, I carefully did the math when I started usng Bio to make sure I didn't go over what Vw allowed so as to avoid warranty issues.

The Jetta tank is 14.5 gallons. 1 gallon is 128 ozs, that equals 1856 ozs.

So B1 would be 18.56 ozs of B100
B2 = 37.12 ozs
B5 = 92.8 ozs (Your 84 ozs is equal to approx B4.5)
B7 = 129.92 ozs (B6.5 = 120.64)

Soooooooo, your 2 60oz'ers are in excess of B5.
 

Plus 3 Golfer

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But Fixmy59bug, who fills up with 14.5 gallons each time?

If your average fill is 14 gallons not 14.5 each time (1792 ounces including the B100), then the mixture in your tank will approach 120/1792 = B6.7 after many fillups - clearly exceeding B5.

Since I'm only concerned about lubricity and my target concentration is B2, I use one quart (32 ounces per fillup) of Bio per fillup. Thus the minimum concentration of Bio in my tank could approach 32/1856 = 1.7% if my fillups were around 14.5 gallons each time. But since my average fillups are around 12.5 gallons, the concentration in my tank will be around 32/1600 = B2. If my average fills drop to 10 gallons the concentration would approach 32/1280 = B2.5.

The bottom line (sgoldste01 has it right), one needs to look at ones average gallons per fillup not the tank capacity when determining how much Bio to add especially when one wants to stay under B5.
 

sgoldste01

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If my main reason for mixing B100 into my tank is to improve lubricity, will adding one quart (resulting in B2 or B2.5) give me the lubricity gains I need to satisfy the HPFP wear scar numbers? Or do I need B5 to get those lubricity gains?
 

Plus 3 Golfer

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B2 is fine. If fact B1 will reduce the wear scar numbers almost to the same level as B2. There have been many studies on this. Search internet for Biodiesel lubricity and the Spicer Study. IIRC, going beyond B2 adds little to nothing to improving lubricity.
 

sgoldste01

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B2 is fine. In fact B1 will reduce the wear scar numbers almost to the same level as B2. There have been many studies on this. Search internet for Biodiesel lubricity and the Spicer Study. IIRC, going beyond B2 adds little to nothing to improving lubricity.
Perfect! Then I see no reason to exceed B2, unless you have a political/environmental objective (which, personally, I already meet by driving a 40 mpg diesel).
 

meowguy

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Has anyone tried mixing fuels? I only have B20 in my area and was thinking of mixing 3 gallons of B20 with every full fill up. I figure so long as B20 is less than 25% of the fill, I should be good as far as meeting VW's recommendation maximum of B5. However, i have no idea if it is safe to mix in the tank.
I have never put in more than 13.5 gallons of fuel at a fillup, it is always a different amount.

How exactly does one measure the percentage of bio-material currently in the fuel tank, and how much to add with the incoming fuel to level out at B1, B5, or B-whatever??? Obviously less is better than more. As has been said, B1 or B2 has the same benefit, so err on the side of less, rather than more when mixing your own.
 
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Plus 3 Golfer

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If you want B2 using B20 mixed with ULSD, then you want to mix 9 parts ULSD to one part B20 for a total of 10 parts. So, % bio in tank = 0.2/10 = 2%. If your max fillup is 13.5 gallons and you want at least B2 in the tank, then you'll want to add (1 part B20 / 10 parts Total)*13.5 gallons = 10% B20 * 13.5 gallons = 1.35 gallons of B20 to get B2.

But since we know B1 offers good lubricity and to make it easy, I'd add one gallon of B20 per fillup. Thus, the follow table would apply based on typical fillups including the B20. So for 1 gallon of B20 added per tank, the %Bio in the tank would approach 20%Bio/Fillup Gallons or:

Fillup ......... % Bio
10 gallons ... B2
11 gallons ... B1.8
12 gallons ... B1.67
13 gallons ... B1.5
14 gallons ... B1.4
15 gallons ... B1.3

If you want to reduce the amount of B20 you add each time, you could add as little as 3 quarts per fillup and still be above 1%. (20%*3/4)/15 gallons = 1% exactly.
 

sgoldste01

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I wouldn't be mixing B20, I'd be mixing B100. But from a previous post in this thread, it sounds like one quart of B100 per tank would yield B2.
 

Fixmy59bug

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Yes, I am fully aware that I am now exceeding the B5 that Vw allows. I did those calculations when I started using bio.

For now I am using <B7 since that is the maximum that Vw allows for europe. I know that means very little on what is allowed here. But I am comfortable with that. If I have an fuel related issue that can be attributed to using B7 instead of the allowed B5, then I will suck it up. But as soon as I am off warranty, I would like to use a maximum of B10 or maybe even B20. I am just not going to use it yet and give anyone an easy out of potential warranty claims.
 

Plus 3 Golfer

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Okay your target is 7% not 5%. That was not abundantly clear.:D

So you need to virtually fillup all the time with at least 12.5 gallons of ULSD if you're adding 120 ounces of B100 to keep around 7% or less. That should not be difficult to do.
 

Fixmy59bug

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Oh, Sorry bout that. I thought I had mentioned it here but I guess I was thinking of the "Biodiesel in 2009+ CRD's" thread.

My post has been edited to reflect that I am now mixing for B7.

And Yes, I always fill up as the light comes on. I haven't ever put in a partial tank because then I can't accurately track my mileage for atleast another tank full.

=^)
 

scirocco*joe

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Great posts all around, folks! Glad I could get an easy yet informative answer. I will begin adding some B20 every fill up to add some lubricity. Still debating how much, though.
 
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