10% Ethanol in Gas
in [Technical]
|
From: Scott Dorsey on 27 Dec 2007 08:47 In article <01c84862$19df0420$cc94c3d8(a)race>, * <nospam(a)this.addy.com> wrote: ><fkgo1g$3js$1(a)panix2.panix.com>... >> >> 10% ethanol won't eat anything. 50% ethanol sure will. > >Actually, 100 percent ethanol would be fine.....It is Methanol - methyl >alcohol - that eats aluminum. I was thinking of eating the rubber, not the aluminum. I believe the aluminum corrosion problems are not specifically due to methanol but due to dissolved water with the methanol, but I am not positive about that. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."
From: Mike Romain on 27 Dec 2007 10:27 Scott Dorsey wrote: > In article <01c84862$19df0420$cc94c3d8(a)race>, * <nospam(a)this.addy.com> wrote: >> <fkgo1g$3js$1(a)panix2.panix.com>... >>> 10% ethanol won't eat anything. 50% ethanol sure will. >> Actually, 100 percent ethanol would be fine.....It is Methanol - methyl >> alcohol - that eats aluminum. > > I was thinking of eating the rubber, not the aluminum. > > I believe the aluminum corrosion problems are not specifically due to > methanol but due to dissolved water with the methanol, but I am not > positive about that. > --scott My owners manual states the water content from the alcohol mix is a large problem and it states 'no matter how many drying agents they 'say' is in them'. The other issue is the old style 'rubber' hoses and things like the 'rubber' tip of the float needle. I almost shudder to think of what the stuff might do to my plastic gas tank, but hopefully the plastic will hold out. I don't know what caused it, but i recently had to replace a carb for a friend because the insides were almost completely dissolved. This is the aluminum frame parts like the float bowl. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 'New' frame in the works for '08. Some Canadian Bush Trip and Build Photos: http://mikeromainjeeptrips.shutterfly.com
From: Kevin Bottorff on 29 Dec 2007 15:09 Mike Romain <romainm(a)sympatico.ca> wrote in news:476e8a79$0$5377$9a6e19ea(a)unlimited.newshosting.com: > Kevin Bottorff wrote: >> Mike Romain <romainm(a)sympatico.ca> wrote in >> news:476d6952$0$5189$9a6e19ea(a)unlimited.newshosting.com: >> >>> Kevin Bottorff wrote: >>>> Mike Romain <romainm(a)sympatico.ca> wrote in news:476c0a93$0$30680 >>>> $9a6e19ea(a)unlimited.newshosting.com: >>>> >>>>> Kevin Bottorff wrote: >>>>>> In spite of my disagreeing with you. At least in the US you can >>>>>> get a exemption if your viechiel is not said by the manufacture >>>>>> to use any ethanol. >>>>>> On the other hand, I know of very few that offically say they >>>>>> can not >>>>>> use it. KB >>>>>> >>>>> You know Kevin, one thing you seem to miss is the nature of what I >>>>> drive. It has the aerodynamics of a brick so needs 'full' power >>>>> to be able to cruise at highway speeds. Any slight loss, means >>>>> the gas pedal has to be mashed to the floor to hold 65 on a hill >>>>> or in a head wind instead of floating along at half throttle. >>>>> This makes a radical difference in gas mileage. >>>>> >>>>> The owners manual for both of my AMC Jeeps also warns of >>>>> drivability >>>> and >>>>> poor performance issues with the mix, let alone forbidding it's >>>>> use in the CJ7 so it is even 'expected'. >>>>> >>>>> Mike >>>>> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 >>>>> 'New' frame in the works for '08. Some Canadian Bush Trip and >>>>> Build Photos: ://mhttpikeromainjeeptrips.shutterfly.com >>>> >>>> just for curiosity sake, what is your gearing, rear end ratio and >>>> tire size? compression ratio of the eng. too. also the dist >>>> advance curve if you know it. KB >>>> >>> I am running tall skinny BFG mud tires in a 33x9.5" size with 3.31 >>> gears. This gives me 2300 rpm at 65 mph in 4th gear of my T5 >>> tranny. I do not use overdrive or 5th gear because of lugging issues >>> which again drops me by 5 mpg when I use it vs 4th. 5th at 65 mph >>> is only 1725 or so RPM which is to low. >>> >>> In other words I am right at the edge of good drivability and gear >>> ratios.... >>> >>> My 258 or 4.2L straight six engine has a 2bbl Weber-Carter BBD >>> feedback carb on it with no computer running any emissions or the >>> feedback circuit so it's totally manually set up. It has an Accel >>> SuperCoil, slightly overgapped plugs, oversized straight pipe >>> leading to a Dynomax SuperTurbo muffler, no cat needed on a CJ7 here >>> in Canada and pretty much stock everything else. >>> >>> Base timing is at 9 deg BTDC with a ported vacuum source and a >>> mechanical plate advance. My mechanical advance comes in full at >>> approximately 1600 rpm. Ported advances with throttle. My light >>> isn't fancy enough for the full advance degree reading. >>> >>> I have had two physical engines and several different distributors >>> in, all giving me the same basic performance curve so figure it's >>> 'right'. >>> >>> I can pass Canadian tailpipe emissions on the ASM 2525 test with 589 >>> NOx , 16 ppm HC and 0.11% CO. >>> >>> I get a stable 23 mpg or 11L/100km highway (checked recently using >>> Esso 91 octane) and it goes like a scalded cat with it's light all >>> fiberglass body. 1st lights up the tires way too easy, 2nd tops out >>> at 52 mph turning 4400 rpm, 3rd pulls hard up to 75 mph, 4th buries >>> the speedo and I have 'no' urge to find out how fast 5th will go. >>> >>> It will purr along on our 400 series highways at a nice 120-140 kph >>> so I can keep up to the big trucks easy. (120 kph in the slow lane >>> usually around here holds up traffic, 100 kph or 65 mph is almost >>> suicidal) >>> >>> We have taken it on three 3000 to 4500 'mile' vacation trips to the >>> east coast even. >>> >>> All in all I/we love the old thing and have a new frame sitting in >>> the back yard getting beefed up before installing in the spring. It >>> needs it's TLC still. It is not forgiving about when needing a tune >>> up either, LOL!... >>> >>> Mike >>> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 >>> 'New' frame in the works for '08. Some Canadian Bush Trip and Build >>> Photos: http://mikeromainjeeptrips.shutterfly.com >> >> I will ponder this awhile and see what I think. >> If I were you I would really want to slap some stock wheels on for a >> full tank trip and use 5th and see what the milage and power >> differences are. It could prove a over geared or not situtation. If >> its as light as I think it should be. probly 2600 lbs or so, it >> should pull those tall gears ok sans a strong headwind if the dist. >> mech advance is truly all in by 1700 rpm. >> If you want to play, when you try a tank of ethanol bump your timeing >> about 3 degrees. KB >> > > I ran stock 31's and used fifth fine when I first bought it. The > mileage was the same if not slightly higher(better) when the odometer > differences are taken into account. > > Which 'way' should I bump the timing? I might be forced to do this > because no more 'real' gas is being sold here in Canada. you need to bump the timeing up 2 to 4 degrees, If it doesn`t ping it is just free efficiency regardless of fuel. But ethanol can take more advance for sure. It may just be that it needs more on the vacuume advance end too. Advance curves are tricky things to play with because there are so many paramaters that affect them. I have spent alot of years experementing with them. > > Now if I could just keep my float needle tips from dissolving.... I > get two years 'max' out of them because I can't always find real gas, > I need a solid needle. I find this confusing because most float needles are epm rubber that will take most any chemicals in stride. It would be nice to find out before your next change out. also off roading is senceitive to fuel pressure being even a bit to high as the float wants to bounce anyway, If your over maby 4 lbs it may be too much for your enviroment. the only reason to need more is if its running lean at WOT. KB PS my 85 F350 460 carb motor is going on 20 years of using 10% ethanol mix with out a carb problem yet. Haven`t even had to overhall the carb yet. > > My engine will pull fine in 5th at 65-70 mph, I just get better > mileage running 4th. In 4th a twitch of the gas pedal compensates for > wind, in 5th, I have to use the whole pedal range. > > Mike > -- Thunder Snake #9 "Protect" your rights or "lose" them.
From: Scott Dorsey on 30 Dec 2007 09:28 Mike Romain <romainm(a)sympatico.ca> wrote: >I am almost out of gas so I will get a good test bed with the fuel mix >in a couple days and play with the timing. You may want to consider adding MTBE, in the form of an "octane enhancer." Not as a permanent measure, but as a diagnostic. It should make no difference... if it does, you know it's either a vapor pressure or a predetonation issue. (And you should have ruled the latter out already.) --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis."
From: jim on 30 Dec 2007 10:08
Kevin Bottorff wrote: > > you need to bump the timeing up 2 to 4 degrees, If it doesn`t ping it > is just free efficiency regardless of fuel. Probably not good advice. From what I can tell he is comparing low-grade regular (87 octane?) with high grade premium (93 octane?). Both probably contain ethanol. The real issue is how to tune it for whatever else what is in the fuel. That probably is going to mean retarding the timing. He may already be set pretty advanced which would explain why he gets much better mileage on high octane. >But ethanol can take more > advance for sure. Yes, that would be true if that was the one thing that makes the 2 fuels different - but it is not. -jim >It may just be that it needs more on the vacuume > advance end too. Advance curves are tricky things to play with because > there are so many paramaters that affect them. I have spent alot of years > experementing with them. > > > > > Now if I could just keep my float needle tips from dissolving.... I > > get two years 'max' out of them because I can't always find real gas, > > I need a solid needle. > > I find this confusing because most float needles are epm rubber that > will take most any chemicals in stride. It would be nice to find out > before your next change out. also off roading is senceitive to fuel > pressure being even a bit to high as the float wants to bounce anyway, If > your over maby 4 lbs it may be too much for your enviroment. the only > reason to need more is if its running lean at WOT. KB > PS my 85 F350 460 carb motor is going on 20 years of using 10% ethanol > mix with out a carb problem yet. Haven`t even had to overhall the carb > yet. > > > > > My engine will pull fine in 5th at 65-70 mph, I just get better > > mileage running 4th. In 4th a twitch of the gas pedal compensates for > > wind, in 5th, I have to use the whole pedal range. > > > > Mike > > > > -- > Thunder Snake #9 > "Protect" your rights or "lose" them. |