E85 Cleaning?

Messages
2,787
Location
Indiana
So my 2018 Silverado 3500HD has the 6.0L gas engine under the hood. It's Flex Fuel compatible. The truck currently has 43k miles on it. Usually ever 20k miles or so, I run 3-4 bottles of Gumout Regane High Mileage through the tank to give me a bit of cleaning. Do you think running a tank or two of E85 through it would provide a decent amount of cleaning to the fuel system, including the injectors?
 
Messages
3,359
Location
Chicagoland
Every tear down I've seen while watching YouTube of engines running E85 look really clean. Whether that's conjecture or not I'm not sure, as they're usually high output, high strung engines.
 
Messages
888
Location
Upper midwest
Originally Posted by Phishin
So my 2018 Silverado 3500HD has the 6.0L gas engine under the hood. It's Flex Fuel compatible. The truck currently has 43k miles on it. Usually ever 20k miles or so, I run 3-4 bottles of Gumout Regane High Mileage through the tank to give me a bit of cleaning. Do you think running a tank or two of E85 through it would provide a decent amount of cleaning to the fuel system, including the injectors?
Yep!
 
Messages
4,232
Location
Kansas
Originally Posted by Phishin
So my 2018 Silverado 3500HD has the 6.0L gas engine under the hood. It's Flex Fuel compatible. The truck currently has 43k miles on it. Usually ever 20k miles or so, I run 3-4 bottles of Gumout Regane High Mileage through the tank to give me a bit of cleaning. Do you think running a tank or two of E85 through it would provide a decent amount of cleaning to the fuel system, including the injectors?
Maybe not! Gumout with Regane is gonna lay down a barrier to prevent ethanol corrosion so it cant inhibit anything. Throwing E85 / Gumout will probably nullify each other. I think its using one or the other but both working against each other seems more likely.
 

Phishin

Thread starter
Messages
2,787
Location
Indiana
Originally Posted by Marco620
Maybe not! Gumout with Regane is gonna lay down a barrier to prevent ethanol corrosion so it cant inhibit anything. Throwing E85 / Gumout will probably nullify each other. I think its using one or the other but both working against each other seems more likely.
I wouldn't put Regane in the E85....... My question was: Would running a tank or two (by itself) of E85 provide any cleaning?
 
Messages
172
Location
Brazil
Originally Posted by Phishin
Do you think running a tank or two of E85 through it would provide a decent amount of cleaning to the fuel system, including the injectors?
To the fuel system? Maybe it could clean some fuel lines and old gas deposits, but i think any dedicated fuel system cleaner will work better. The true cleaning effect of ethanol would be on the inside of your engine after the fuel is burned.
 
Messages
209
Location
ChicagoLand USA
don't most engine manufacturers who offer flex fuel E-85 use recommend more frequent oil changes (Ford does with my 2007 F150 Flex Fuel 5.4 3V)...isn't the more frequent oil changes because the oil may be dirtier due to the use of that higher alcohol content in the fuel cleaning something???... Bill
 
Messages
128
Location
pennsylvania
High content ethanol is incompatible with most cleaner additives used in gasoline. That's why flex/e85 has none currently at the pumps, at best you will just be wasting money. E85 is a waste of time anyhow unless your getting it free the mpg drop offsets the now minor price difference. Now if you want to spend money and custom tune you can do some things. As it sits though flex vehicles don't optimize when you use e85. They simply adapt to it you lose mpg and power on a stock vehicle.
 
Messages
293
Location
Arizona
Originally Posted by Phishin
So my 2018 Silverado 3500HD has the 6.0L gas engine under the hood. It's Flex Fuel compatible. The truck currently has 43k miles on it. Usually ever 20k miles or so, I run 3-4 bottles of Gumout Regane High Mileage through the tank to give me a bit of cleaning. Do you think running a tank or two of E85 through it would provide a decent amount of cleaning to the fuel system, including the injectors?
Maybe not! Gumout with Regane is gonna lay down a barrier to prevent ethanol corrosion so it cant inhibit anything. Throwing E85 / Gumout will probably nullify each other. I think its using one or the other but both working against each other seems more likely.
The parts that make the engine an E85 capable engine are upgraded from standard 10% ethanol capable ones. They're built to run on E85 so the"ethanol corrosion" thing is not relevant.

That's 85% corn alcohol. Of course it's going to clean things out.
 
Messages
1,639
Location
South Carolina
Ethanol is an excellent solvent. My 2002 Tahoe is flex fuel, and I run 3-4 tanks of E85 through it every 50k miles followed by changing the fuel filter.
 
Messages
2,015
Location
Middle of Iowa
High content ethanol is incompatible with most cleaner additives used in gasoline. That's why flex/e85 has none currently at the pumps, at best you will just be wasting money. E85 is a waste of time anyhow unless your getting it free the mpg drop offsets the now minor price difference. Now if you want to spend money and custom tune you can do some things. As it sits though flex vehicles don't optimize when you use e85. They simply adapt to it you lose mpg and power on a stock vehicle.

While the first statement about additive incompatibility with E85 is true, the rest of it is not.

If there is more than a ~25% price difference between the fuel you normally use and E85, it is cost effective to use E85...this is especially true in vehicles that require premium fuel. Will you get slightly lower MPG - yes. Will you get lower MP$ - only if the difference is less than 25%.

MANY of today's engines that can run E85 will, in fact, push the timing limits, and offer more power on E85. Just using E85 in comparison with gas can offer more maximum power due to the cooling effects of E85. Several OEM's even publish higher power ratings for their engines when running E85. I have NEVER heard, nor does the science support, losing power when running E85.

I run premium in my 6.2L Silverado as required...under full throttle on a warm day, I will record timing retard due to knock on full throttle. When running E85, I never record timing retard, even when towing on a hot day with AC running.
 
Messages
128
Location
pennsylvania
Ok guess my car happened over 4 tanks of the exact same driving to drop 25% mpg. Then oddly enough gain it back ever since. You talk about science yet mention nothing to back that up. Besides likely being someone on the selling corn end of ethanol. A stock flex fuel car does not gain mpg or power running e-85. Put it on a Dyno and spend $$$ get a custom e85 tune on a built motor sure. On a street car the injectors have to throw more fuel when your running the corn swill, plugs 1 step cooler(burns hotter). End result on a factory stock car warranty intact, you not only do not gain but lose power and mpg. Which companies on stock flex fuel card advertise more power and mpg with e-85? What does recording timing retard do to prove more power and equal or increased mpg. Only that the timing is too aggressive for the fuel and cooling of that motor in those conditions. Simply not knocking does not equal more power.

The impact to fuel economy varies depending on the energy difference in the blend used. For example, E85 that contains 83% ethanol content has about 27% less energy per gallon than gasoline (the impact to fuel economy lessens as ethanol content decreases).
1596561226390.png

Energy.gov › afdc › ... › Ethanol
Ethanol Benefits and Considerations - Alternative Fuels Data Center
 
Messages
2,015
Location
Middle of Iowa
Ok guess my car happened over 4 tanks of the exact same driving to drop 25% mpg. Then oddly enough gain it back ever since. You talk about science yet mention nothing to back that up. Besides likely being someone on the selling corn end of ethanol. A stock flex fuel car does not gain mpg or power running e-85. Put it on a Dyno and spend $$$ get a custom e85 tune on a built motor sure. On a street car the injectors have to throw more fuel when your running the corn swill, plugs 1 step cooler(burns hotter). End result on a factory stock car warranty intact, you not only do not gain but lose power and mpg. Which companies on stock flex fuel card advertise more power and mpg with e-85? What does recording timing retard do to prove more power and equal or increased mpg. Only that the timing is too aggressive for the fuel and cooling of that motor in those conditions. Simply not knocking does not equal more power.

The impact to fuel economy varies depending on the energy difference in the blend used. For example, E85 that contains 83% ethanol content has about 27% less energy per gallon than gasoline (the impact to fuel economy lessens as ethanol content decreases).
View attachment 26277
Energy.gov › afdc › ... › Ethanol
Ethanol Benefits and Considerations - Alternative Fuels Data Center


Yes, like I said, there is ~ 25% difference in fuel economy (you even re-stated it)...which if you understand that there is roughly a 33% difference in energy content in the fuel should show you right off the bat that the engine and ECM is doing something to use the energy available more efficiently. (hint, advancing timing)

Because ethanol contains close to 34% less energy per unit volume than gasoline, E85 FFVs have a lower mileage per gallon than gasoline.[23][24] However, this lower energy content does not translate directly into a 34% reduction in miles per U.S. gallon, because there are many other variables that affect the performance of a particular fuel in a particular engine, though for E85 the effect becomes significant. E85 will produce lower mileage than gasoline, and actual performance may vary depending on the vehicle. Based on EPA EPA-rated mileage for all 2006 E85 models, the average fuel economy for E85 vehicles was 25.56% lower than unleaded gasoline.[3] When making price comparisons it has to be considered that E85 has octane rating of about 104 and could be used as a substitute for premium gasoline.

Here is just one example of an engine manufacturer quoting higher power levels with E85 in their flex fuel vehicles...

1596736939686.png


I apologize, but I can't seem to find the SAE paper I was thinking of on E85 producing more power in IDENTICAL engines due to the cooling effect. I know I have it printed on my desk at work, and the next time I am in the office, I will find the number and post a link if it is still available. Otherwise, I will post the document number, and you can buy yourself a copy.

Summary:
Do I lose power on E85 - NOPE, usually you gain power, and at the very least, break even
Do I lose MPG on E85 - YUP, usually ~25%
Do I lose money on E85 - depends on the cost ratio between the "normal" fuel you use and the price of E85

While I do live in the middle of Iowa, I can assure you I have no interest in "corn lobbies, corn prices, etc.", I am a mechanical systems engineer focusing on machine control and design.
 
Messages
2,015
Location
Middle of Iowa
Ok, I found the paper...



Some quotes to help you out...but seriously, it is a great paper and well worth the read if you actually care about how E85 effects engine operation for SI engines.

Don't confuse "thermal efficiency increase" with MPG increase...that is not the case. The engine is using the thermal engine available more efficiently, while using a larger VOLUME of fuel.

1596738597384.png


1596738626371.png


1596738670866.png
 
Messages
209
Location
ChicagoLand USA
my experience and the experience of my brother mirror what DriveHard shows above...his Chevrolet had more horsepower (as mentioned in the manual) but gas mileage dropped to basically make it a moot point in using E-85 in Illinois...

I mentioned elsewhere in this thread already but again my F150 with the Flex-Fuel motor seems to have more gettin up and go with E-85 but gas mileage drops a couple MPGs...there is also a caution to change the oil more often and not to use E-85 exclusively with my F150...for me, the price savings or added pep is rarely worth using it so I don't...

YMMV...literally... ;)

Bill
 
Messages
172
Location
Brazil
Ok guess my car happened over 4 tanks of the exact same driving to drop 25% mpg. Then oddly enough gain it back ever since. You talk about science yet mention nothing to back that up. Besides likely being someone on the selling corn end of ethanol. A stock flex fuel car does not gain mpg or power running e-85. Put it on a Dyno and spend $$$ get a custom e85 tune on a built motor sure. On a street car the injectors have to throw more fuel when your running the corn swill, plugs 1 step cooler(burns hotter). End result on a factory stock car warranty intact, you not only do not gain but lose power and mpg. Which companies on stock flex fuel card advertise more power and mpg with e-85? What does recording timing retard do to prove more power and equal or increased mpg. Only that the timing is too aggressive for the fuel and cooling of that motor in those conditions. Simply not knocking does not equal more power.

The impact to fuel economy varies depending on the energy difference in the blend used. For example, E85 that contains 83% ethanol content has about 27% less energy per gallon than gasoline (the impact to fuel economy lessens as ethanol content decreases).
View attachment 26277
Energy.gov › afdc › ... › Ethanol
Ethanol Benefits and Considerations - Alternative Fuels Data Center

Here in Brazil, more than 90% of the cars on the road are flex, and every single manufacturer advertise 2 power figures, one with ethanol ( E100 not E85) and the other one with gas. Ethanol always is the highest number.

Everyone knows around here, like @DriveHard mentioned, that you lose mpg but gain in power. The math is, if ethanol cost less than 30% of gasoline, it's worth it.

Here are some of the many comparissons videos betwen gas vs E100 on the same stock engine.



GAS

E100 (look ate the comparisson at @6:32)
 
Messages
3,442
Location
Austin, TX MSA
The price difference between gasoline and ethanol was more pronounced in Brazil when we visited about a year and a half ago than it is here in the USA. Gas was over 4 reais a liter whereas etanol was in the 2.60-2.70 range. We had a rental car and drove quite a bit, found the ethanol to be more cost effective. Suffice it to say though that the Renault Duster we rented had very little power with either fuel type, compared to what we are used to in the USA. Especially on the climb up to Campos do Jordao (5300 feet), foot to the floorboard, about 80-90 KMH was all it would do.

Meanwhile, my new-to-me Navigator is flex-fuel capable, and states in the owners' manual to make 10HP more on e85. I've ran a couple of tanks and the mileage penalty is not as bad as I thought it would be, about 1.5mpg so far. I can obtain the fuel for less than $1.50, and gas is edging closer to $1.90. I'm going to keep running it.
 
Last edited:
Messages
209
Location
ChicagoLand USA
...just be aware with your Navigator unless Ford has changed their recommendation...using E85 will require more frequent oil changes...it is easy to run the math on whether or not E85 will work for anyone...with my F-150 rarely is E85 cheap enough for me to use it in the ChicagoLand area...I have several tankfuls and as reported earlier in this thread found there to be a slight increase in felt power (which I freely admit might be the placebo effect) with a couple to few MPGs loss...

good luck with your choice

Bill
 
Messages
328
Location
Brittany, France
Talking about pronounced price difference between ethanol and gas, RON95 gasoline is 1.40€ a liter usually (slightly less since covid) and E85 is 0.60 a liter or less in my area.
 
Top