E85, Injector Gunk & Seafoam.
May 27, 2009, 05:46 PM
#31
Here are most of the useful posts from that thread for people who don't want to read the whole thing. Most of these posts are from 'thiazole', who is a chemist that actually tested the injector gunk, along with a couple from others in the thread:
Alright, I finished my analysis of this stuff, and my finding is very unexpected. I think it will probably surprise everyone else as well. This doesn't appear to be forming because ethanol is "such a good solvent" but because ethanol is a poor solvent. I suppose it should have been obvious when others said that it "washes right off with gasoline". Why would something that ethanol is selectively dissolving wash off with gasoline? If this were something in rubber or from our fuel tanks, wouldn't that imply that gasoline would dissolve it even more readily than E85?
Alright, so what is this stuff? It is a appears to be a very large petroleum based hydrocarbon, similar to Vaseline. There isn't a single hetero-atom in the molecule (ie, the entire molecule is comprised of hydrogens and carbons), but the molecule is very large. It is also completely aliphatic (ie, only single bonds in the structure - no double or triple bonds). Where did it come from? I can only think of two different sources it could be coming from. It is either something that is mixed in with the rubber hoses that is meant to dissolve away in the gasoline, or it is a trace impurity in the 15% gasoline that is in E85 that wasn't separated during the fractional distillation process. Because it is such a large molecule, it wouldn't be very soluble in ethanol and could easily crash out of solution at the injector.
Alright, so what is this stuff? It is a appears to be a very large petroleum based hydrocarbon, similar to Vaseline. There isn't a single hetero-atom in the molecule (ie, the entire molecule is comprised of hydrogens and carbons), but the molecule is very large. It is also completely aliphatic (ie, only single bonds in the structure - no double or triple bonds). Where did it come from? I can only think of two different sources it could be coming from. It is either something that is mixed in with the rubber hoses that is meant to dissolve away in the gasoline, or it is a trace impurity in the 15% gasoline that is in E85 that wasn't separated during the fractional distillation process. Because it is such a large molecule, it wouldn't be very soluble in ethanol and could easily crash out of solution at the injector.
Well, here is what I did just so everyone is clear. I filled a 40mL vial with E85 and blew it dry with nitrogen gas and mild heating (about 150*F). After there was no fuel left, I placed it under high vacuum to remove any remaining volatiles for about an hour. I was left with a clear sticky residue that smelled bad - like nasty frying oil. I dissolved this sample in the NMR solvent and analyzed it and it IS the same goo that was on the injector. There was smaller amounts of some other stuff in it as well, but the same peaks I saw in the black goo were in this residue. The black goo IS coming from the E85. It isn't naturally black, though. I suspect it just has soot mixed in with it that is giving it the color.
So the next challenge is figuring out why is this crap in our fuel, and if it is in everyone's fuel (particularly people who aren't having this problem).
So the next challenge is figuring out why is this crap in our fuel, and if it is in everyone's fuel (particularly people who aren't having this problem).
Gum in E85!
--------------------------------------------------------------------------------
Ok, it isn't chewing gum, of course. I think gum is a generic term for high MW sticky solids. Anyway, if you look at table 1 in this article, it mentions that there is up to 5mg of "solvent-washed gum content"/100mL and up to 20mg "unwashed gum content"/100mL. It think this might be what is sticking to our injectors.
Later in the article it also mentions that mixing E85 and pump gas WILL cause additives to crash out and stick to the injectors and intake runners. I don't think this is what we are seeing since I saw the molecule in a clean sample of E85, but it does open that possibility for others who are mixing.
(link to doc that didn't work)
--------------------------------------------------------------------------------
Ok, it isn't chewing gum, of course. I think gum is a generic term for high MW sticky solids. Anyway, if you look at table 1 in this article, it mentions that there is up to 5mg of "solvent-washed gum content"/100mL and up to 20mg "unwashed gum content"/100mL. It think this might be what is sticking to our injectors.
Later in the article it also mentions that mixing E85 and pump gas WILL cause additives to crash out and stick to the injectors and intake runners. I don't think this is what we are seeing since I saw the molecule in a clean sample of E85, but it does open that possibility for others who are mixing.
(link to doc that didn't work)
So I'm in a brief meeting intermission, but I really am convinced that this stuff is the "gum" mentioned in that article. I found another paper that defined the gum as the residue left after evaporation of the fuel. I'm going to see if I can get ahold of the author of that paper and see if I can figure out exactly what the "gum" is to verify that this is what we are seeing.
Thiazole, I think have a lead on an exact chemical name to follow up on in solving this mystery. Read the following:
"Overuse of additives with E85 may result in poor vehicle operation. RFA has also made certain recommendations about appropriate detergent treatment of E85. Some detergents, such as polyisobutylene amine, have performed poorly in FFV operation. At some blend levels, these additives may precipitate out of the blend resulting in excessive fuel system deposition."
This info was taken from a pdf I found while researching for a graduate project on E85 I am currently doing, http://www.afdc.energy.gov/afdc/pdfs/41853.pdf
So polyisobutylene amine might be the gum that is precipitating and this is a straight up fuel quality issue and not a fuel environment based one...
"Overuse of additives with E85 may result in poor vehicle operation. RFA has also made certain recommendations about appropriate detergent treatment of E85. Some detergents, such as polyisobutylene amine, have performed poorly in FFV operation. At some blend levels, these additives may precipitate out of the blend resulting in excessive fuel system deposition."
This info was taken from a pdf I found while researching for a graduate project on E85 I am currently doing, http://www.afdc.energy.gov/afdc/pdfs/41853.pdf
So polyisobutylene amine might be the gum that is precipitating and this is a straight up fuel quality issue and not a fuel environment based one...
It wouldn't surprise me if gasoline evaporates faster than ethanol in which case you could see this stuff crash out (since it isn't soluble in ethanol). I doubt it happens in the gas tank, though, or the entire fuel system would be covered in this gunk, which I haven't seen. What probably happens is after turning the engine off, whatever E85 is left on the tips of the injectors and in the intake manifold evaporates off leaving behind this gum. After doing this several times, you get a significant amount of gum formation.
It is dissolved in the E85, but just barely so that it readily crashes out at the injector tip. You can't filter it. It would be like filtering out hard water to remove hard water stains. It can't be done until after it crashes out, but by then it is too late.
You wouldn't want to filter this out even if you could, anyway. The E85 I'm buying has about 10mg of this gum/100mL which means it has about 6000mg per tank. The amount of gum required to clog up an injector is probably only 20mg. The amount to clog a fuel filter would probably be about 1000mg or less. If you could filter it, you'd be clogging several filters per tank. When we scale up the synthesis of a drug, if there is an intermediate that forms a gum and requires filtration, it can actually kill that synthesis and send us back to the drawing board. Gums SUCK and there really aren't many good ways to deal with them other than just dissolving them away.
You wouldn't want to filter this out even if you could, anyway. The E85 I'm buying has about 10mg of this gum/100mL which means it has about 6000mg per tank. The amount of gum required to clog up an injector is probably only 20mg. The amount to clog a fuel filter would probably be about 1000mg or less. If you could filter it, you'd be clogging several filters per tank. When we scale up the synthesis of a drug, if there is an intermediate that forms a gum and requires filtration, it can actually kill that synthesis and send us back to the drawing board. Gums SUCK and there really aren't many good ways to deal with them other than just dissolving them away.
Q from someone: I was just thinking that if the gum is a component of the gas that's added to the ethanol to make the E85 (the other 15% that's not ethanol) then adding a little more gas that is more highly refined might push the cross over point far enough that we'd never see it... ?
Yes - I suspect that when they add the gasoline to the ethanol that the gum is at or very near the saturation point. If you consider that 10 gallons of E85 only has 1.5 gallons of gasoline in it, adding another 1.5 gallons of non-gum containing gasoline like racing gas would decrease the relative concentration of the gum to gasoline by 50% away from saturation. I think this alone would make a big difference and be pretty affordable if it works.
May 27, 2009, 05:53 PM
#32
Rather than being scary, I think the thread was very informative and you can deduce possible solutions to the issue.
It appears that only some people have this issue and it may be possibly from the station's blend of fuel and additives. So, some of us just may be lucky with the stations we use and never have the issue.
For those that do have the issue, it appears that the 'gunk' is soluble in gasoline, meaning it easily dissolves and goes into solution in gasoline (as well as other chemicals such as sea foam, mineral spirits, toluene, xylene, etc).
It hasn't been tested yet in that thread, but a solution may simply be to run a tank of pasoline once in a while, to dissolve any of the precipitated gunk from the injector tips and the back of the valves and/or run an E-85 injector cleaner (such as the gumout linked in that thread) or sea foam.
If the solution is easy as that, then this mystery has a happy ending.
It appears that only some people have this issue and it may be possibly from the station's blend of fuel and additives. So, some of us just may be lucky with the stations we use and never have the issue.
For those that do have the issue, it appears that the 'gunk' is soluble in gasoline, meaning it easily dissolves and goes into solution in gasoline (as well as other chemicals such as sea foam, mineral spirits, toluene, xylene, etc).
It hasn't been tested yet in that thread, but a solution may simply be to run a tank of pasoline once in a while, to dissolve any of the precipitated gunk from the injector tips and the back of the valves and/or run an E-85 injector cleaner (such as the gumout linked in that thread) or sea foam.
If the solution is easy as that, then this mystery has a happy ending.
May 28, 2009, 03:13 AM
#35
Evolved Member
Thread Starter
iTrader: (6)
Join Date: Jul 2005
Location: Charleston, SC
Posts: 1,228
Likes: 0
Received 0 Likes
on
0 Posts
So I switched back to gasoline last night in preparation for my trip, and man, its sucks! Ha Ha! The car runs soo much different on gasoline, and its been almost 2 years since I have ran gasoline through it, so I couldn't even remember what it was like. I am sure that by the time I get back to Charleston with 2,000 miles + added to the odometer, my black gunk woes will be gone, and I can go back to E85.
Funny, but it looks like a cure to the gunk can be Tephra's map switching...
Funny, but it looks like a cure to the gunk can be Tephra's map switching...
Now that I have read through all of this. I will probably run a tank of 93 through once every other month just to be safe. Thanks Tephra for a map switching/cleansing mod! 
May 28, 2009, 06:36 AM
#37
Evolved Member
iTrader: (18)
Join Date: Jul 2005
Location: Columbia, SC
Posts: 1,063
Likes: 0
Received 0 Likes
on
0 Posts
That seems to be the trick right now. I never would have thought I would be glad that there weren't more E85 stations in this state. It forces me to use 93 from time to time.
May 28, 2009, 09:26 AM
#38
Evolved Member
iTrader: (1)
Join Date: Jul 2004
Location: Los Angeles
Posts: 851
Likes: 0
Received 0 Likes
on
0 Posts
So I switched back to gasoline last night in preparation for my trip, and man, its sucks! Ha Ha! The car runs soo much different on gasoline, and its been almost 2 years since I have ran gasoline through it, so I couldn't even remember what it was like. I am sure that by the time I get back to Charleston with 2,000 miles + added to the odometer, my black gunk woes will be gone, and I can go back to E85.
Funny, but it looks like a cure to the gunk can be Tephra's map switching...
Funny, but it looks like a cure to the gunk can be Tephra's map switching...
Jun 5, 2009, 09:44 PM
#39
I tried to find some of this product with no success.
Gumout Flex-Fuel Vehicle Fuel Injector Cleaner
In fact, all of the local auto parts stores I visited sell the Gumout line, but none had even heard of the Injector Cleaner for Flex-Fuel Vehicles.
Has anyone been able to find this? Has anyone looked? Would any fuel injector cleaner product be just as good?
Rislone fuel injector cleaner states it is good for gas, diesel, and E85. So, can I conclude that all injector cleaners are pretty much the same?
Bars Products Rislone fuel injector cleaner
Gumout Flex-Fuel Vehicle Fuel Injector Cleaner
In fact, all of the local auto parts stores I visited sell the Gumout line, but none had even heard of the Injector Cleaner for Flex-Fuel Vehicles.
Has anyone been able to find this? Has anyone looked? Would any fuel injector cleaner product be just as good?
Rislone fuel injector cleaner states it is good for gas, diesel, and E85. So, can I conclude that all injector cleaners are pretty much the same?
Bars Products Rislone fuel injector cleaner
Jun 6, 2009, 01:05 AM
#40
The problem with a lot of the injector and fuel system cleaners is that they contain pteroleum of some sort. Oil mixed with ethanol that is not 100% will cause any water to seperate and gather causing rust or a poor running engine. Nothing like rusty fuel system parts
I'd say run the gas and add some Redline SI-4 fuel system cleaner it cleans and is supposed to protect against rusting so I imagine it must coat metal parts somehow
Maybe you could contact Redline and see what they say. The bottle says it contains petroleum distillates. I have used this stuff for years and I think it's good.
I wanna be like you Jim
Link for info and to even buy online although I've seen it at PepBoys
http://www.redlineoil.com/products_fueladditives.asp
SI-1 Complete Fuel System Cleaner
SI-1's injector and valve detergent is a concentrated package of the most powerful high-temperature detergents available to clean gasoline fuel injectors or carburetors, intake valves and combustion chambers and can clean injectors to nearly 100% efficiency in one treatment. The cleansing effect on injector deposits can raise fuel economy approximately 12% or even greater, depending on the condition of the injectors.
SI-1 also contains detergents and a synthetic upper cylinder lubricant which will help clean pollution control valves and can reduce octane requirements by two numbers. SI-1 also protects the fuel system from rust.
Use one bottle with a full tank or use in smaller doses for continued maintenance, as SI-1 treats up to 100 gallons. Safe for continual use.
I'd say run the gas and add some Redline SI-4 fuel system cleaner it cleans and is supposed to protect against rusting so I imagine it must coat metal parts somehow
Maybe you could contact Redline and see what they say. The bottle says it contains petroleum distillates. I have used this stuff for years and I think it's good.
I wanna be like you Jim
Link for info and to even buy online although I've seen it at PepBoys
http://www.redlineoil.com/products_fueladditives.asp
SI-1 Complete Fuel System Cleaner
SI-1's injector and valve detergent is a concentrated package of the most powerful high-temperature detergents available to clean gasoline fuel injectors or carburetors, intake valves and combustion chambers and can clean injectors to nearly 100% efficiency in one treatment. The cleansing effect on injector deposits can raise fuel economy approximately 12% or even greater, depending on the condition of the injectors.
SI-1 also contains detergents and a synthetic upper cylinder lubricant which will help clean pollution control valves and can reduce octane requirements by two numbers. SI-1 also protects the fuel system from rust.
Use one bottle with a full tank or use in smaller doses for continued maintenance, as SI-1 treats up to 100 gallons. Safe for continual use.
Jun 6, 2009, 01:11 AM
#41
Oh yeah one more thing .. I'm pretty sure Advance auto or one of those retailers listed on Gumout website could order the E85 specific cleaner for you.
Ethanol is a cleaner by nature so I imagine anything to get rid of the gunk would be solvent based. Berrymans fuel cleaner contains toluene,xylene,benzene or some chemical similar and I imagine the Seafoam is similar in that it is a solvent based cleaner. Solvents aretypically stronger and arguably better cleaners but definitely more harsh on your fuel system compnents IMO.
Ugh it's late and I've had a few so......
I'm done rambling for now
Ethanol is a cleaner by nature so I imagine anything to get rid of the gunk would be solvent based. Berrymans fuel cleaner contains toluene,xylene,benzene or some chemical similar and I imagine the Seafoam is similar in that it is a solvent based cleaner. Solvents aretypically stronger and arguably better cleaners but definitely more harsh on your fuel system compnents IMO.
Ugh it's late and I've had a few so......
I'm done rambling for now
Jun 6, 2009, 07:56 AM
#43
Evolving Member
iTrader: (5)
Join Date: Mar 2007
Location: Kansas
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
For those that switches back between 93 and E85, do you empty yor tank (using the return line) or just wait until the low fuel light comes up and fill up the tank full with the other fuel and switch map after the new fuel is in?
Do you notice any driving/idling issue on the first few miles/minutes after the switch?
Maybe I should have opened a new thread for this question.
Do you notice any driving/idling issue on the first few miles/minutes after the switch?
Maybe I should have opened a new thread for this question.
Jun 6, 2009, 08:15 AM
#44
Evolved Member
iTrader: (56)
Join Date: Feb 2005
Location: vegas baby....
Posts: 3,070
Likes: 0
Received 0 Likes
on
0 Posts
here's a quick question.... does e85 corrode our old fuel hoses? specifically the one from firewall to fuel rail.... could it possibly break up the rubber somehow to small particles?
Last edited by nils; Jun 14, 2009 at 03:07 PM. Reason: duh... said brake hose instead of fuel hose....
Jun 10, 2009, 12:57 PM
#45
Evolved Member
iTrader: (18)
Join Date: Jul 2005
Location: Columbia, SC
Posts: 1,063
Likes: 0
Received 0 Likes
on
0 Posts
For those that switches back between 93 and E85, do you empty yor tank (using the return line) or just wait until the low fuel light comes up and fill up the tank full with the other fuel and switch map after the new fuel is in?
Do you notice any driving/idling issue on the first few miles/minutes after the switch?
Maybe I should have opened a new thread for this question.
Do you notice any driving/idling issue on the first few miles/minutes after the switch?
Maybe I should have opened a new thread for this question.