Ethanol Fuels

[Grumpy Bear]

Ethanol E-** 

 

6/30/2022

 

Recently the price of Regular Grade Gasoline has risen high enough that E-85, at least for the time being, has become a viable alternative on a cost per mile basis; so...I started running it in my 2015 Flex Fuel 4.3 V6. There is allot to learn and allot to get use to. 

 

Usually this fuel gets discussed on the basis of it's stellar octane value and it's ability to enhance performance. But I think the discussion can go further such as the effect it has on the motors oiling system. The 90+ octane crowd can make an even stronger case for cost effective use. Is there more? 

 

I asked a trusted friend for advice on the naming of this topic and while I loved the name, "CLEAN BURN FUELS" I've been here long enough to know what rabbit holes not to go down and this looked like one of those. Only from the standpoint that many clean fuels such as hydrogen and propane are logistical nightmares. That considered, I wanted to keep it in the arena of a fuel we have access to with many vehicles 'turn key' ready and more minimally so to make ready. I also wanted to keep it practical and shy away from the abstract/theoretical rabbit hole afore mentioned.  

 

In a separate post to follow I'd like to tackle the elephant in the room. Fuel consumption. 

 

In the mean time, put on those thinking caps. 

 

 

Edited July 3, 2022 by Grumpy Bear

[Grumpy Bear]

Fuel Economy

 

This graph is based on each fuels BTU value per pound using the EPA fuel references for each. Yep, there is tons of anecdotal testimonials that may say something other. This is what the chemistry has to say. 

 

The read isn't exactly straight forward since most of us use an E-10 fuel anyway which is 9% maximum by rule of the ATF. That said you would find  your new value and subtract the old. Example; I'm currently running 75% ethanol so I would subtract 3.4% from 25.7% to know how much hit my economy is going to take. 22.3% is that value in my case.  

 

 

 

Ethanal is a single carbon chain fuel, (C2H5OH)  unlike gasoline which is a mixture of may hydrocarbons. The EXACT mix in gasoline is BOUNDED by Federally mandated 'fences' and it's vapor pressure to meet the markets and the laws requirements. Point to that is the EXACT BTU value of gasoline isn't laid in concrete. However it is VERY close to the EPA bench mark with a variation of a few percent from crude source field to field and season to season. About 3% maximum. Ethanol on the other hand is a singular value.  So this chart will be for all intent and purpose the basis for any comments I may have on the topic. 

Edited June 30, 2022 by Grumpy Bear

[Grumpy Bear]

Required Reading

 

https://www.eesi.org/papers/view/fact-sheet-a-brief-history-of-octane

 

 

Edited July 2, 2022 by Grumpy Bear

[Grumpy Bear]

AKI Index of E-10/15 E85 Blends

 

Actual ethanol content on this chart is 1% lower than the listed value. ATF demands that alcohol be denatured.

 

 

These AKI values are ONLY for fuels as delivered at a pump or by the operator blending ONLY 87 E-10 or 88 UNL-88 and E-85. These ARE not the values for blending E85 and any other pump gasoline with an octane greater than 88. Those fuels, such as 91/93 octane E-10 blends are NOT MADE with 84 octane straight run gasoline but contain ever larger dosing of BTEX. I can make a chart for that if you need something stronger on request. 

 

Naturally the numbers above 84% ethanol are based on the data for 84 AKI based gasoline. 

 

Locally my station is running 75% ethanol so Pepper is a happy camper running 105+ AKI fuel. No wonder there is zero KR timing pull back. 

 

 

[Black02Silverado]

Not to side track but it would be interesting to see a UOA of Pepper using E85 100% from one oil change to the next.

[Grumpy Bear]

3 hours ago, Black02Silverado said:

Not to side track but it would be interesting to see a UOA of Pepper using E85 100% from one oil change to the next.

 

Explain please what this would look like. I want understand the request completely. Does this mean two samples with one being gasoline and the second E-85...or something else?

[swathdiver]

In making my chart, I chose to use Sunoco's octane rating, E15 is 88 octane, E85 is 99 octane which makes it .15714 between each alcohol percent to the next.

 

I could never find the feds standards, they didn't seem to have much consistency and have not looked in about 2 years since I went with my own chart using Sunoco's data.

 

This is look a part of the chart:

 

[customboss]

Because of ancient meaningless state laws higher altitude regions get stuck with the baseline gasoline being the lowest possible octane and so our E15 in Alamosa from Maverik might be as low as 86 octane ( 1 avg octane higher than our regular, 85) or as high as 88 if we get a baseline blend gasoline that is made for other markets..... at any rate the L3B on my truck the way I drive it likes E15 even of lower octane, that extra 5% ethanol really burns clean, even with crappy baseline gasoline from Phillips. 

Maverik :Phillips 66 831978 - SDS E15.pdf

Edited July 3, 2022 by customboss
add unbranded Phillips SDS E15

[Black02Silverado]

15 hours ago, Grumpy Bear said:

 

Explain please what this would look like. I want understand the request completely. Does this mean two samples with one being gasoline and the second E-85...or something else?

Basically, when you do the next  oil change, run nothing but E85 until you do the next oil change and take a sample.  Would be interesting to see how using 100% E85 would effect the UOA.

[Z45]

E85 fuels tend to leave behind more acids from combustion byproducts that dilute the oil in the crankcase, causing faster oil degradation.

[customboss]

10 hours ago, elcamino said:

E85 fuels tend to leave behind more acids from combustion byproducts that dilute the oil in the crankcase, causing faster oil degradation.

Just the opposite based on testing of post 2001 engines that can burn it efficiently. I think what you just shared is a fallacy promoted by anti ethanol promoters. 
I’ve been testing fuels and lubricants since 1980. Grumpy Bears 2.4 Dizzy did better burning higher levels of ethanol than E10 and its had troubles not related to fuel composition. His 4.3 “flex fuel” truck is using E85 with exceptional results. 
Testing shows less stress on engine oils using higher that 10% ethanol. 
Most acid formation comes from NOx and carbon deposits. Ethanol fuel in gaseous form or liquid cleans those out via a solvent effect. 
Closed fuel systems and positive crankcase venting limit the ethanol residing in oil and fuel system absorbing atmospheric water thus modern spark engines/trucks  are safe  to tote it around and burn it. 
 

[Black02Silverado]

12 hours ago, elcamino said:

E85 fuels tend to leave behind more acids from combustion byproducts that dilute the oil in the crankcase, causing faster oil degradation.

Might be the case on pre 2001 vehicles but mine using E85 have shown better results in their UOA when I use E85. 

 

This is why I asked Grumpy to do an oil change, run E85 100% until the next oil change and then do a UOA.  Curious to see his results.  Unfortantly we moved and E85 isn't as available as before so I can't do that. 

[Grumpy Bear]

3 hours ago, Black02Silverado said:

This is why I asked Grumpy to do an oil change, run E85 100% until the next oil change and then do a UOA.  Curious to see his results.

 

This current oil change has been on high alcohol content. 47% on first tank and progressing to the peak of 75%. Did the swap 400 miles before this OCI. I refuel at 50% like clockwork so it took a few tanks to get to peak pump percent. This current OCI will reflect whatever it is you wish to see. Note however. This OCI is Cummins Valvoline Restore 10W30 and I intend to leave it a good long while. I expect first sampling at 5K miles. 

[Grumpy Bear]

 

 

[Grumpy Bear]

On 7/3/2022 at 8:33 AM, customboss said:

Because of ancient meaningless state laws higher altitude regions get stuck with the baseline gasoline being the lowest possible octane and so our E15 in Alamosa from Maverik might be as low as 86 octane ( 1 avg octane higher than our regular, 85) or as high as 88 if we get a baseline blend gasoline that is made for other markets..... at any rate the L3B on my truck the way I drive it likes E15 even of lower octane, that extra 5% ethanol really burns clean, even with crappy baseline gasoline from Phillips. 

Maverik :Phillips 66 831978 - SDS E15.pdf 89.37 kB · 3 downloads

 

Octane comes from somewhere and that somewhere is EITHER increased aromatics OR oxygenation compounds such as ethers or alcohols. MTBE, ETBE, and TAME

 

https://www.eia.gov/outlooks/steo/special/pdf/mtbe.pdf

 

There is naturally occurring aromatics and ADDED aromatics used to boost octane levels. The difference is significant. As you have pointed out to me on many occasions these aromatics are the source of particulate carbon and varnishes. Ergo 87 octane regular with ADDED aromatic levels is dirtier than 87 octane E-10 made from lower level straight run and ethanol additions. Same is true of E-85 when NOT blended with doses of 91/93 non-alcohol pump gas. It's just a cleaner fuel.

Edited July 7, 2022 by Grumpy Bear