Interesting info I found scouring the web and thought I would share it with you all. Its on the black goo found in E85
[BEGINNING OF QUOTE] "E85 fuel is a strange beast, it is 85% ethanol and 15% gasoline. This creates two unique problems; (if you don't want the read all the science, the bottom line is add HEET Water Remover and STP fuel system cleaner for ethanol several times a year and your good to go.)
Ethanol is hygroscopic (loves to absorb water) but when combined with 15% gasoline, the water will drop out of the ethanol at only 0.5% concentration. What that means is, in the morning when it's cool with high humidity the E85 is sucking water out of the air, then letting it drop out of solution and settle in the bottom of your tank. Fortunately there is a very easy solution; once or twice a year add a water remover that has isopropyl alcohol base like HEET Water Remover. The brand isn't important, what you need is isopropyl alcohol based additive. Rubbing alcohol will work, but you will need to add a lot of it, because it contains 30% water to keep it from evaporating too fast when your Honey rubs it on your back .
The second unique problem is, the 15% gas in E85 has detergent added to it, one of which is Poly Iso-Butylene. It is a excellent detergent in gasoline, but it SUCKS when it is in a 50% or greater solution of ethanol. For some complex reasons, it actually becomes insoluble and plates out on injectors and valves. The EPA has know this since 2007, but has not changed the rules that force gas companies to add it to ALL gasoline (except racing fuel). GM and Ford have both tested E85 engines and found that in normal in-town driving the fouling can become significant in as little as 5,000 miles. At highway speeds the fouling slows significantly, to the point that it is a non-issue. Again, there is an easy solution; use an injector cleaner that is formulated for Ethanol.
The specific detergent in E85 that is causing the majority of the fouling is Poly Iso-Butylene. So the problem is the additives the EPA mandates in E85. The additives in the E85 are the same they mandate in gas, but the Ethanol will react with them over time and form an insoluble deposit (sludge) in the tank and on the injector walls. The EPA knows the additives are no good in ethanol, but they won't change the rule. The highest concentration of ethanol in gas tested that did not form deposits is 15% ethanol.
The Petroleum Engineering Professor I have been talking to about the E85 fouling told me that methylal is the most effective, but not the only, solvent for the Poly Iso-Butylene fouling. He also told me that the Poly Iso-Butylene causes fouling only in ethanol blends above 50% and that once the detergent falls out of solution it is not readily dissolved in pump gas or E85. Other injector cleaners may be effective in removing fouling, but note that Methylal is no longer used in any fuel additive, thank you EPA. But STP fuel system clean for ethanol is good at dissolving Poly Iso-Butylene that has dropped out of solution in the gas tank. Once the gas tank is clean, there is no reason to use flex fuel injector cleaners since the ethanol content of pump gas is well below 50%, the Poly Iso-Butylene will not drop out of solution." Otherwise use the STP once a month if you use E85 24/7 or do the gasoline flush. I did find out that the injector fouling occurs mostly when you are doing in-town driving, not at higher RPM.
Gasoline Flush, running the tank near empty (not gauge empty, real fuel tank empty), run 2 tanks of 93 Shell pump gasoline through, then run near empty and go back to E85, your injectors will be clean. I was told that doing this every 6 to 8,000 miles would not only clean the injectors, but the "sludge" that can build up in the fuel tank, without plugging filters. If you do mostly highway driving, don't worry about it. Maybe once every 15 to 20,000 miles, run a couple of tanks of Shell through and you are good to go. Never add gas to a tank that has E85 if you can avoid it, the sludge build up in your tank will be much worst (read get ready to change filters)
Also this was an issue with throttle stutter - rubber end caps on dw injectors melted over, some injectors more than others. don't use rubber tipped injectors with E85.
And E85 produces many more acids when combusted in an internal combustion engine, mostly due to the extra oxygen that comes in with the molecule - which is also the reason for the extra power. Thus change your oil every 3k miles cause it will get extremely high in acid levels if you dont." [END OF QUOTE]
Hope this info help all of you out.
[BEGINNING OF QUOTE] "E85 fuel is a strange beast, it is 85% ethanol and 15% gasoline. This creates two unique problems; (if you don't want the read all the science, the bottom line is add HEET Water Remover and STP fuel system cleaner for ethanol several times a year and your good to go.)
Ethanol is hygroscopic (loves to absorb water) but when combined with 15% gasoline, the water will drop out of the ethanol at only 0.5% concentration. What that means is, in the morning when it's cool with high humidity the E85 is sucking water out of the air, then letting it drop out of solution and settle in the bottom of your tank. Fortunately there is a very easy solution; once or twice a year add a water remover that has isopropyl alcohol base like HEET Water Remover. The brand isn't important, what you need is isopropyl alcohol based additive. Rubbing alcohol will work, but you will need to add a lot of it, because it contains 30% water to keep it from evaporating too fast when your Honey rubs it on your back .
The second unique problem is, the 15% gas in E85 has detergent added to it, one of which is Poly Iso-Butylene. It is a excellent detergent in gasoline, but it SUCKS when it is in a 50% or greater solution of ethanol. For some complex reasons, it actually becomes insoluble and plates out on injectors and valves. The EPA has know this since 2007, but has not changed the rules that force gas companies to add it to ALL gasoline (except racing fuel). GM and Ford have both tested E85 engines and found that in normal in-town driving the fouling can become significant in as little as 5,000 miles. At highway speeds the fouling slows significantly, to the point that it is a non-issue. Again, there is an easy solution; use an injector cleaner that is formulated for Ethanol.
The specific detergent in E85 that is causing the majority of the fouling is Poly Iso-Butylene. So the problem is the additives the EPA mandates in E85. The additives in the E85 are the same they mandate in gas, but the Ethanol will react with them over time and form an insoluble deposit (sludge) in the tank and on the injector walls. The EPA knows the additives are no good in ethanol, but they won't change the rule. The highest concentration of ethanol in gas tested that did not form deposits is 15% ethanol.
The Petroleum Engineering Professor I have been talking to about the E85 fouling told me that methylal is the most effective, but not the only, solvent for the Poly Iso-Butylene fouling. He also told me that the Poly Iso-Butylene causes fouling only in ethanol blends above 50% and that once the detergent falls out of solution it is not readily dissolved in pump gas or E85. Other injector cleaners may be effective in removing fouling, but note that Methylal is no longer used in any fuel additive, thank you EPA. But STP fuel system clean for ethanol is good at dissolving Poly Iso-Butylene that has dropped out of solution in the gas tank. Once the gas tank is clean, there is no reason to use flex fuel injector cleaners since the ethanol content of pump gas is well below 50%, the Poly Iso-Butylene will not drop out of solution." Otherwise use the STP once a month if you use E85 24/7 or do the gasoline flush. I did find out that the injector fouling occurs mostly when you are doing in-town driving, not at higher RPM.
Gasoline Flush, running the tank near empty (not gauge empty, real fuel tank empty), run 2 tanks of 93 Shell pump gasoline through, then run near empty and go back to E85, your injectors will be clean. I was told that doing this every 6 to 8,000 miles would not only clean the injectors, but the "sludge" that can build up in the fuel tank, without plugging filters. If you do mostly highway driving, don't worry about it. Maybe once every 15 to 20,000 miles, run a couple of tanks of Shell through and you are good to go. Never add gas to a tank that has E85 if you can avoid it, the sludge build up in your tank will be much worst (read get ready to change filters)
Also this was an issue with throttle stutter - rubber end caps on dw injectors melted over, some injectors more than others. don't use rubber tipped injectors with E85.
And E85 produces many more acids when combusted in an internal combustion engine, mostly due to the extra oxygen that comes in with the molecule - which is also the reason for the extra power. Thus change your oil every 3k miles cause it will get extremely high in acid levels if you dont." [END OF QUOTE]
Hope this info help all of you out.
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