E-85 gasoline

C

cannon

Member
thoughts on using E-85 with the weber carb. i am trying just for the fun of it, seems i need to"hog" out the jets a little. any idea how much?
 
I would try some first, before making any jet size adjustments. I ran a tank in my 28 with standard zenith carb. Ran okay. If I planned on running it all the time, I might do alot more testing. Plugs, water temp, and such, before expermenting.
 
The chemically correct air-fuel ratio for gasoline is ~14.6:1; straight (neat) ethanol is 9.0:1. Technically you need to increase the area of the jet by roughly 40% to run 100% EtOH. I'd start at about 25% for E85 and work up from there. You might be able to use a small drill to find the exact diameter, then figure out what size will get you the right size bigger hole. Sounds like a good experiment - please report back.:)
 
Oh, what a dummy! Don't know if you're still out there or not, but if you are, forget drilling jets: just turn the enrichment screw (GAV) until you get the mixture adjusted for the E85! I'll bet a doughnut that's why Henry was able to run ethanol in the 1920s without any carburetor tricks. Ain't Model As grand? :p
 
Old182 said:
Oh, what a dummy! Don't know if you're still out there or not, but if you are, forget drilling jets: just turn the enrichment screw (GAV) until you get the mixture adjusted for the E85! I'll bet a doughnut that's why Henry was able to run ethanol in the 1920s without any carburetor tricks. Ain't Model As grand? :p
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I was wondering why you didn't recommend just opening the GAV :)

what is the benefit to running E-85? I thought I had heard it costs more and gives you less MPG?
 
Old182 said:
Oh, what a dummy! Don't know if you're still out there or not, but if you are, forget drilling jets: just turn the enrichment screw (GAV) until you get the mixture adjusted for the E85! ...
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Is the GAV effective throughout the entire range of throttle opening? I thought it was only effective at low engine speeds?
 
I run e85 in one of my A's and I get about 30% less mileage with it (as I do in my Flex Fuel modern rig as well)

Rule of thumb I have found with E85, if it's 30% less $ per gallon than regular fuel, then it is worth it as you tend to get 30% worse mileage from it... You adjust your GAV for best performance and do keep in mind it does not give you quite as much power as regular fuel, so don;t plan on as much giddy-up-go from your 40 horses :)
 
Thanks, MrTube: Things come to me in dribs and drabs - must be the age factor - I dunno. Well, here's the nerdy stuff: Ethanol (EtOH) contains just under 35wt% oxygen and there are no Btus in oxygen. Btus = range or fuel economy and that's why you get poorer fuel economy (about 35%) with neat EtOH. However, the latent heat of vaporization of ethanol is much greater than an all-hydrocarbon gasoline (0.93 MJ/kg vs. 0.18 MJ/kg for the exceptionally nerdy) and so it cools the incoming air charge considerably (note the cooling sensation when you put alcohol on your skin). This provides a denser charge to the cylinder and allows the engine to make more power at any given throttle setting, or for any given throttle setting it makes more power; i.e. you go 50 mph with less throttle because of the denser air. This does not cancel out the lack of heat energy, but it helps some (Cessna recently did work using an ether and produced some nice data to support this). Racers use EtOH but prefer methanol (MeOH) because its latent heat of vaporization is the highest of the alcohols (1.17 MJ/kg), even though it contains 50% oxygen (really bad fuel economy) and is quite corrosive. Regarding the GAV, my car will know if I turn the knob at any speed, so I believe it works throughout the entire throttle range. If Model Ts were able to run ethanol or gasoline in the 1920s, then our 80+ year old machines have the unique ability to be easily adjusted for a lean-burning fuel without mechanical modification, fuel economy issues notwithstanding. The other reason to run it has to do with a deep distrust of the oil-producing countries, but that's for another forum. ;)
 
should have mentioned i am running a prair of 81's -lion head-headers and other goodies. just for the fun of it, jets in the 81;s are easy to remove etc. etc. just wondering, nothing else to do in this 100 degree 85% humitity at 72 years old...:)
 
In a pinch (quite a few years ago) when I was bone-dry out of gas in my driveway, I started my A and warmed it up for a few minutes by squirting model airplane fuel into the carb (castor oil + nitromethane + ?), then poured in a gallon of kerosene into the tank. Ran OK (not great) for the mile or two it took to get to the gas station and fill it up.
 
I'm surprised it even started on nitro - it's hard to light with a match in a petri dish! I've heard stories that here in the Hudson Valley Model A trucks were started on gasoline then run on straight kerosene all day hauling fruits & veggies to NY City in the old days (60 miles). Guess it's true!
 
I had heard the once the engine is running on gas, that you could switch to kerosene...but had never wanted to try that out.

Marc
 
Years ago when going to school, I did not have much money, but I had access to kerosene and lacquer thinner. Car started and ran fine with the GAV more open. The exhaust fumes smelled much better, too. It did not seem to hurt the engine, but I was just a kid and was not worried about engine damage.
 
Old182 said:
... Well, here's the nerdy stuff: Ethanol (EtOH) contains just under 35wt% oxygen and there are no Btus in oxygen. Btus = range or fuel economy and that's why you get poorer fuel economy (about 35%) with neat EtOH. However, the latent heat of vaporization of ethanol is much greater than an all-hydrocarbon gasoline (0.93 MJ/kg vs. 0.18 MJ/kg for the exceptionally nerdy) and so it cools the incoming air charge considerably (note the cooling sensation when you put alcohol on your skin). This provides a denser charge to the cylinder and allows the engine to make more power at any given throttle setting, or for any given throttle setting it makes more power; i.e. you go 50 mph with less throttle because of the denser air. This does not cancel out the lack of heat energy, but it helps some (Cessna recently did work using an ether and produced some nice data to support this). Racers use EtOH but prefer methanol (MeOH) because its latent heat of vaporization is the highest of the alcohols (1.17 MJ/kg), even though it contains 50% oxygen (really bad fuel economy) and is quite corrosive. ... ;)
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Speaking nerd-to-nerd, maybe we should be clear that that latent heat of vaporization effect applies to the purer alcohols, not to the 10% gasohol mixtures we commonly buy. In the purer form, the alcohol molecules are hydrogen bonded to each other, which requires extra energy input to separate them and get them to vaporize. When they are the minor component in a solution of gasoline, they are more likely to exist as individual, non-hydrogen bonded molecules, which are much more willing to make the leap into the gas phase. In fact, such forced integration of dissimilar molecules makes the gasoline molecules themselves much more eager to leave town too, i.e., raises the vapor pressure over that of normal hydrocarbon-only gasoline. Since E85 contains 70-83% actual ethanol, it's in between the extremes I've referred to; I'll have to take the word of engineers how it works out in practice.

Steve
 
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Many of the the old 1920-30's 2 and 4 cylinder tractors had two fuel tanks a small one for gasoline and a larger one for what they called power fuel (kerosene). They would start on gasoline and when they got warmed up switched to the power fuel and run all day on it. Since the Model A is about the same technology don't know why it wouldn't work. We we hunting once when we were kids with some friends that ran dozers and such for a living. Ran out of gasoline in they ole Chevy truck about 1950 model with the old in line 6. They had a fuel tank for the dozers in the back of truck so we pumped a couple gallons of diesel fuel in and it ran until we could get some gasoline not great, really smoked, but ran. :D
 
The Fordson was really a kerosene tractor,and the two cyl.John Deeres were.The JD's had a little tank on the back of the big tank,you would start it on gas,warm it up,and switch it to kero once it was warm.Then you switched it back long enough to purge the carb before you shut it off.If you stalled it or forgot and shut it off with a carb full of kero you were up the creek.I worked for a JD dealer back in the late 70's,the old fellow that had been working on the two cyls.all his life was trying to train me about them.The old guys were dying off and there were still a lot of them in use here.He always told me how lucky I was that nobody was using the kero any more,at least twice a week he would have to run out to a farm and drain the carb,the lines,flush it with gas and get it started again.There was always somebody that would forget to purge or stall them.That did not look like fun,100 degree days,hot tractor in a field,playing with hot fuels,hand flywheel start,twist your guts out trying to get it to fire again.That was when they were new,but right after the war local ag companies made gas available to farmers at a price that made it foolish to keep kero too.
 
Thanks for the clarification, Steve. It would seem, then, that E85 users could take advantage of the cooling effect of the ethanol, whereas those of us with 10% EtOH fuels can't. I'm aware there's a 1 psi RVP EPA waiver for ethanol fuels, but I thought it was because of the ethanol only, not the effect ethanol has on the bulk gasoline. What's your take on that?
 
Old182 said:
Thanks for the clarification, Steve. It would seem, then, that E85 users could take advantage of the cooling effect of the ethanol, whereas those of us with 10% EtOH fuels can't. I'm aware there's a 1 psi RVP EPA waiver for ethanol fuels, but I thought it was because of the ethanol only, not the effect ethanol has on the bulk gasoline. What's your take on that?
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I don't know the answer for sure. I do know that I read a C&E News article years ago about the oil companies having a hard time meeting vapor pressure specs when they were first required to add ethanol--the gasoline molecules would rather be with their own kind and are more eager to leave an ethanol mixture than they are the hydrocarbon-only stuff. Raoult's law violation was hard to fight but made a nice classroom example. Somehow they did it, or maybe they were forced to get a waiver, to accomodate both physical chemistry and the corn lobby--but that's just a speculation.

STeve
 
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