Tek-Tips is the largest IT community on the Internet today!
Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!
-
Congratulations JAE on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!
E85 Fuel 2
- Thread starter steve383
- Start date
patprimmer
New member
If you have a normal steel fuel tank and lines they will rust.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
Also, wherever you have an aluminum or magnesium component, the Ethanol will initiate corrosion. All OEM applications have a high percentage of stainless steel and reinforced nylon/plastic componentry. Anodizing parts will delay the onset of corrosion, but its not if, but when.
Franz
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
Franz
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
-
1
- #43
I can give you my experiences with ethanol vehicles, and would solicit further response especially regarding corrosion, fuel pumps, seals, etc. in modern fuel injected vehicles. I know of others that have successfully converted cars to run on E98 (running well for at least the last half year), and I personally have been doing experiments on my own 1990 toyota supra and I'm currently running E98 with no modifications to the stock vehicle(truly zero mods). This is a 7MGE engine, naturally aspirated, inline 6 toyota with EFI and automatic spark advance and closed-loop air/fuel ratio adjustment via an exhaust oxygen sensor (factory stock, bought in virginia). I started by increasing ethanol percentage by 5 or 10% and did this all the way up to 85% ethanol before i noticed slightly rough idling on cold start. This is due to open loop operation during warmup I suspect. Once the loop closes with the oxygen sensor and the air/fuel ration is appropriately adjusted everything smooths out, and I've even got better 0-60 times and good high speed cruising than on 100% gasoline. I'm doing mileage testings now. Let me know how serious you think corrosion would be for this modern a vehicle. I remember when everyone was cautioning using biodiesel in diesel vehicles w/out modification because of fuel line compatibilities, etc... and now almost everyone that has done the testing says it can be used w/out modification in most diesel engines. I wonder if the same will prove true for ethanol? On that note, what do you think of mixing 5% water in with the ethanol? I'm sure that will get your hair raised.
patprimmer
New member
I have personally seen a cars where 10% methanol and 1% acetone was added to the tank to raise the octane so it could run 90 octane at 11:1 compression. The methanol separated out, and after about 3 months, the tank rusted, and the fuel pump and carby got extensively contaminated with brown sludge. The fuel filter was regularly blocked with rust particles.
I cleaned the tank and treated it and the lines with phosphoric acid type rust converter. After a thorough clean out and a very large fuel filter being fitted the car ran fine on straight 100 octane avgas.
If your Toyota is not showing problems, it might have some protective coating on the tank and lines. How long these will protect for is anyones guess.
How are you correcting your A:F ratio at full throttle when the computer is open loop.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
I cleaned the tank and treated it and the lines with phosphoric acid type rust converter. After a thorough clean out and a very large fuel filter being fitted the car ran fine on straight 100 octane avgas.
If your Toyota is not showing problems, it might have some protective coating on the tank and lines. How long these will protect for is anyones guess.
How are you correcting your A:F ratio at full throttle when the computer is open loop.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
Methanol is much more corrosive than ethanol... the two are really not even in the same ballpark in terms of corrosion, so your story does not surprise me. Not being a toyota engine management system specialist, I don't know exactly how/when my toyota is running in closed/open loop, I've just been piecing together information from engineers and technicians I've talked to that have experience with these types of systems, and from the way my engine runs. That being said, I was not aware that at full throttle the car would be in open loop, that seems like that would not be a good idea and air/fuel ration would depend on altitude, fuel quality, etc. Even on gasoline at full throttle you would want to regulate the air/fuel ratio based on the 02 sensor feedback for emissions reasons, no? Is it the norm for full throttle operation to be open loop? That being said, other than when I'm testing 0-60 times I can't say I really ever operate at full throttle. I do wonder if my tank and lines have some sort of anti-corrosion coating. I guess time will tell, although this does beg the question of how hard it really is to reliably retrofit certain vehicles for ethanol operation. Are there any potential longterm problems that warming up my car lean (on ethanol) and running rough for 3 or 4 minutes on startup would cause? Is there any simple way you can think of to richen the ratio (more fuel) in open loop at cold start to prevent this?
patprimmer
New member
Yes
Fit bigger injectors. The computer won't know they are bigger.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
Fit bigger injectors. The computer won't know they are bigger.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
Patprimmer,
So far I'm at a zero cost ethanol conversion, rather than fitting bigger injectors I'm wondering if there is another less costly solution (like manually adjusting the mass flow meter to trick the computer into thinking less fuel is going to the cylinders). Were you answering "yes" to the question about potentially damaging my engine by running lean on startup? If i'm not running a load (i.e. I warm up at idle and don't drive till the engine is operating in closed loop), will lean running on startup hurt my engine over the long run? Thanks for the clarification.
So far I'm at a zero cost ethanol conversion, rather than fitting bigger injectors I'm wondering if there is another less costly solution (like manually adjusting the mass flow meter to trick the computer into thinking less fuel is going to the cylinders). Were you answering "yes" to the question about potentially damaging my engine by running lean on startup? If i'm not running a load (i.e. I warm up at idle and don't drive till the engine is operating in closed loop), will lean running on startup hurt my engine over the long run? Thanks for the clarification.
To clarify my last post. What I meant to say with the mass flow meter idea was "(like manually adjusting the mass flow meter to trick the computer into thinking more air is going to the cylinders than actually is)." It was suggested I relax the flapper in the mass flow meter a notch or two to do this, and the result would be a richer mixture at startup (open loop) but shouldn't affect closed loop operation. This should smooth out cold start lean condition, no?
DesignOutsourcing
Automotive
It might be easier to put a manual, time or temperature switched resistor in series or parallel with the AF meter. Hook up a multimeter to the AF meter, see which way the resistance goes when you move the flap, then use a variable resistor (in parallel to lower the resistance if the resistance goes down as the flap opens, or in series if the resistance goes up when the flap opens.) once you know what resistance to use, hook up a resistor on a manual or time or temp switch. Other thing would be a switched extra injector in the plenum. hope this helps. cheers, derek
Join us at
Join us at
Typical automotive flurocarbon o-rings will swell +100% in ethanol. We had to change every fuel injector component to 17% chromium alloys to meet VW test requirements for the Brazilian market. You can put whatever you want in your tank but don't come running to me when it falls apart in a few months or years.
Going back to some thoughts on ethanol presented earlier in this thread, I think this person puts it all into an interesting perspective.
Enjoy,
rmw
Enjoy,
rmw
This is a reply to dgallup:
What 'typical' flurocarbon materials are you referring to? I haven't seen data to indicate that the swelling is that much in any materials I know of that are used in fuel systems. Could you expound further? Do you have any references to studies done on this? And what was the reasoning behind the chromium alloys? Was this to prevent possible electrolytic corrosion due to water in the fuel? What era of VW was this?
thanks,
This is a general reply:
Btw, I did a smog test on my ole' 1990 supra on E98, came out with alot of unburnt hydrocarbons on startup when cold (combination of missing and poor vaporization of fuel i suspect). It passed all tests on the so-called 'fast pass' meaning in the 1st 15 seconds at 15mph (50% load) and 25mph (25% load) it passed all the emissions tests (for NOx, CO, and Hydrocarbons, 02 and C02 were also measured). CO was imperceptible (0.00%), and NOx were middle of the passing range (416ppm), HCs were close to allowed max (100ppm). I was told this is typical in the first 15seconds of the test, and that since it was clean enough to pass in the first 15 seconds it must be quite clean overall, because if given more time at each state these numbers would almost certainly decrease. Apparently the way the equipment is set up if it doesn't pass at 15 seconds it checks again at 45 and 75seconds and at each successive time you should see cleaner results.
What 'typical' flurocarbon materials are you referring to? I haven't seen data to indicate that the swelling is that much in any materials I know of that are used in fuel systems. Could you expound further? Do you have any references to studies done on this? And what was the reasoning behind the chromium alloys? Was this to prevent possible electrolytic corrosion due to water in the fuel? What era of VW was this?
thanks,
This is a general reply:
Btw, I did a smog test on my ole' 1990 supra on E98, came out with alot of unburnt hydrocarbons on startup when cold (combination of missing and poor vaporization of fuel i suspect). It passed all tests on the so-called 'fast pass' meaning in the 1st 15 seconds at 15mph (50% load) and 25mph (25% load) it passed all the emissions tests (for NOx, CO, and Hydrocarbons, 02 and C02 were also measured). CO was imperceptible (0.00%), and NOx were middle of the passing range (416ppm), HCs were close to allowed max (100ppm). I was told this is typical in the first 15seconds of the test, and that since it was clean enough to pass in the first 15 seconds it must be quite clean overall, because if given more time at each state these numbers would almost certainly decrease. Apparently the way the equipment is set up if it doesn't pass at 15 seconds it checks again at 45 and 75seconds and at each successive time you should see cleaner results.
Many people are mistaking the Methanol (Wood Alcohol) for Ethanol in this thread, Methanol is fairly corrosive. Ethanol will deteriorate NATURAL rubber, but does not seem to hurt the synthetic rubber that's usually used in fuel systems. also, if you are in the places where 10% ethanol is used, you will find out if you have none compatable material. (e85 does not erode/harden 8.5 times as much as E10, seems to be only slightly more reactive with materials)
Another simple way to recalibrate a EFI car on e85 is boost the fuel pressure. 10% seems to do it. (45psi to 50psi on a 95 saturn). This does make the fuel pump work harder, but has not seemed to cause any problems so far for us. Also, I have had no problems on a 89 camaro (TBI 5.0l) and 93 Honda Civic running at 50%-60% ethanol other than running rough for a few seconds in the winter (in Minnesota). Using 100% E85 has given a check engine light when running full throttle, and then it runs rough (running open loop) until the ignition is turned off and on, and the Camaro has had at least 30% ethanol for around 6 years now (I originally mixed e85 with regular unleaded for octane boosting, at that time it cost the same. No problems, in fact the injectors work better now than when I bought the car. (they used to get stuck when the car sat for over 3-4 days. 180,000 miles so far, original fuel pump, lines, fuel tank, and injectors.)
As far as I have been able to tell, you can put in 20% ethanol without rejetting a carb, 20-30% tends to run a bit lean, above that you should rejet it. One of these days I'm going to test exact amounts of extra fuel flow needed, since I have not been able to find out how much is needed for ethanol. (Methanol is around 100% more fuel, back 25 years ago when I used that for racing)
Our fuel milage is no worse than 5% worse if I'm not driving. (car is faster, and I tend to rev it up more w/ we run e85 in it; I should go back to regular gas for a few tankfuls on the wife's Saturn and see how much worse my milage is than hers to get more data points for comparison)
and I do not work for (or have investments that I know of) in anything related to Ethanol production or related industries, I just hate being dependant on OPEC. SMR
Another simple way to recalibrate a EFI car on e85 is boost the fuel pressure. 10% seems to do it. (45psi to 50psi on a 95 saturn). This does make the fuel pump work harder, but has not seemed to cause any problems so far for us. Also, I have had no problems on a 89 camaro (TBI 5.0l) and 93 Honda Civic running at 50%-60% ethanol other than running rough for a few seconds in the winter (in Minnesota). Using 100% E85 has given a check engine light when running full throttle, and then it runs rough (running open loop) until the ignition is turned off and on, and the Camaro has had at least 30% ethanol for around 6 years now (I originally mixed e85 with regular unleaded for octane boosting, at that time it cost the same. No problems, in fact the injectors work better now than when I bought the car. (they used to get stuck when the car sat for over 3-4 days. 180,000 miles so far, original fuel pump, lines, fuel tank, and injectors.)
As far as I have been able to tell, you can put in 20% ethanol without rejetting a carb, 20-30% tends to run a bit lean, above that you should rejet it. One of these days I'm going to test exact amounts of extra fuel flow needed, since I have not been able to find out how much is needed for ethanol. (Methanol is around 100% more fuel, back 25 years ago when I used that for racing)
Our fuel milage is no worse than 5% worse if I'm not driving. (car is faster, and I tend to rev it up more w/ we run e85 in it; I should go back to regular gas for a few tankfuls on the wife's Saturn and see how much worse my milage is than hers to get more data points for comparison)
and I do not work for (or have investments that I know of) in anything related to Ethanol production or related industries, I just hate being dependant on OPEC. SMR
Just a note on this issue.
I've been running E85 in a 2002 Subaru WRX for almost 2 years now with no problems of any kind. I started out at moderate levels and discovered the stock ECU would run out of fuel trim authority at about 33% E85 in the tank and throw a CEL for "too lean". In spite of the CEL the car ran great (actually better performance than with 100 octane unleaded race gas )
I swapped in over sized injectors ( went from 420 cc/min to 550 cc/min ) and could run 100% E85 with no CEL's or problems of any kind due to the E85. For cold start improvement in very cold weather (< 20 deg F) I simply added 2 gallons of extra gasoline to the tank.
I just did a tally and so far I have run in excess of 500 gallons of E85 through the car, I am at 52,000 miles (about 9,000+ on the E85 blends, and have seen no fuel system compatibility issues at all.
Stock fuel lines are mild steel ( magnetic test ) injectors are OEM 550 cc/min STi injectors for the Japanese 2.0 L Sti's, fuel pump is a Walbro 255 L/hr after market high flow pump, and I recently bumped the static fuel pressure from 43psi to 50 psi to give me a bit more headroom, using the old DSM hotrodder trick of crushing the OEM fuel pressure regulator top to increase the static pressure.
Turbocharged engines LOVE this fuel and I get about 92% of my gasoline fuel milage on the E85.
Full write up on the experiment is at:
Larry
I've been running E85 in a 2002 Subaru WRX for almost 2 years now with no problems of any kind. I started out at moderate levels and discovered the stock ECU would run out of fuel trim authority at about 33% E85 in the tank and throw a CEL for "too lean". In spite of the CEL the car ran great (actually better performance than with 100 octane unleaded race gas )
I swapped in over sized injectors ( went from 420 cc/min to 550 cc/min ) and could run 100% E85 with no CEL's or problems of any kind due to the E85. For cold start improvement in very cold weather (< 20 deg F) I simply added 2 gallons of extra gasoline to the tank.
I just did a tally and so far I have run in excess of 500 gallons of E85 through the car, I am at 52,000 miles (about 9,000+ on the E85 blends, and have seen no fuel system compatibility issues at all.
Stock fuel lines are mild steel ( magnetic test ) injectors are OEM 550 cc/min STi injectors for the Japanese 2.0 L Sti's, fuel pump is a Walbro 255 L/hr after market high flow pump, and I recently bumped the static fuel pressure from 43psi to 50 psi to give me a bit more headroom, using the old DSM hotrodder trick of crushing the OEM fuel pressure regulator top to increase the static pressure.
Turbocharged engines LOVE this fuel and I get about 92% of my gasoline fuel milage on the E85.
Full write up on the experiment is at:
Larry
- Status
Similar threads
