classes of gas

[G.M.]

Gas is produced for differant months and each month has it's own class. I happened to pick the worst gas of the year for my boiling temp tests. The lowest class is E with the lowest boiling point. But this is good for testing because I'm in the hottest area useing the lowest boiling point fuel which should provide the worst conditions. That is if class E is delivered in Florida. Go to www.eps-hane.com/techtips5.html this shows the boiling points and months produced for the various classes. I need a few more hot days over 85 degrees to complete my tests in the 85 range would like to do more at 95 when it gets that hot. I have all the temperatures pined down on the various fuel components and the cures to reduce the heat in the critical areas. Will post the results after a few more tests. G.M.

[mrtexas]

I don't understand why you would be doing gasoline boiling temperature tests? There are probably a dozen specifications on gasoline to insure it evaporates properly in your carburetor. The idea is to insure it works OK in your car for the particular ambient temperature and altitude where your car is located.

Gasoline does not have a single boiling point. Specs for gasoline are typically at 10%, 50%, 90% and end point of a boiling range. These are % distilled of a sample in a laboratory automated D86 single pot distillation machine.

Gasoline also differs besides time of year like summer and winter by geography. The gasoline at any time of the year is different in Florida and Pennsylvania. It also differs by altitude. Besides distillation points there are specs for vapor pressure. Vapor pressure is the pressure reading on a closed bottle of gasoline in a 100F water bath. Vapor pressure is high in the winter and low in the summer. You need a high vapor pressure to evaporate gasoline in a cold place. Typically vapor pressure of gasoline is around 15psi in the winter an 6 psi in the summer. The object of the differing grades is to make gasoline evaporate properly in your engine's carburetor and fuel injection system.

There are also intermediate grades between summer and winter.

I was a chemical engineer in an ExxonMobil refinery for 31 years before retiring two years ago.

[ford38v8]

Mr Texas, please explain to us morons why your so called gasoline needs so much damned engineering by you highly paid chemical engineers and still mucks up our valves and boils in our carburetors? Isn't it true that gasoline used to be simply a worthless byproduct from the production of kerosene? Now with all your fancy chemical engineering, it costs over $4.00 a gallon and is all but functionally worthless to us morons who keep buying this crappola you call gasoline? Please also explain why YOU don't understand why a concerned consumer is trying his best to offer a fix for us morons who are forced to buy the stuff you experts are calling gasoline?

Don't take it personal, I just have a problem with all gasoline company chemical engineers these days. And before you snap back at me for my rage, yes, I do realize that you were "just following orders", but at the same time, I'm offended by phoney innocence to the damage done by the collaboration of Corporate Corn and Oil Company PACs.

GM, I and all us morons thank you for your effort. We understand why you are doing your fuel tests, even if Chemical Engineers do not.

[barryfromvictoria]

ford v-8--- i am sure the the engineers had nothing to do with banning lead or zinc or to mandate corn gas i think it is them epa guys that are dictating what is going into gasoline the engineers work with what they are allowed and don`t have anything to do with the price. blame the moron politicions and the moron oil executives---barry

[Vic Piano]

Contrary to popular beliefs, politicians, the President and/or supply and demand have nothing to do with the price of gas at the pump, the price fluxions are caused by the Wall Street speculators...

[46ford]

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I don't think the engineers are blending fuel to work in our old cars. Newer vehicles have much different fuel systems than my '46. That's probably why my full sized sedan gets 29 mpg and my '46... well let's just say a lot less than that. We might have to use additives but I doubt they're gonna tailor the fuel to my old carburetor. I just live with hard starting when hot.

As for the price... demand is the reason it stays high. I don't even want to think of the price point where I would have to decide to stay home from work. Why would gas be $2.00 when we continue to buy it at $4.00?

[Sid the Maineiac]

The unrest and turmoil in the Mid-east along with higher demand in China,India and other developing nations is causing Wall Street speculators to drive the price up by $.50 per gallon. It seems the harder we work to find alternative energy,the higher the price of gas goes!! Go figure!

[Mart]

I don't think it is good form to launch a personal attack on a contributor when that contributor gives good information freely and in a helpful manner. That's first hand knowledge from an expert who was very recently directly involved in the area being discussed.

We all dislike the price of fuel. Try buying it here in the UK.

The discussion was about fuel being blended to different grades to optimise it for different altitude and ambient temperatures.

Interesting stuff, I didn't realise it was that specific.

Take the info in the spirit it was given, not as a springboard for a tirade of abuse.

Mart.

[Juergen]

Gas is expensive? compared to what? What do we pay for a bottle of drinking water, or a loaf of bread? Do the math. If the producers get around $100/ barrel, and with 42 petroleum gallons per barrel, that comes to about $2.50 a gallon for the oozy substance. Add in the state and federal taxes, it comes to about $3.00 per gallon. I doubt there would be much demand for this stuff sold in the store for us "morons" to convert to something we can use. I'll let the chemists do this for me. Do you know of any other commodity that has a 1/3 markup from raw material to finished product?

[Old Henry]

I'm not sure that testing gas by one person in one town in the United States is going to establish anything useful for all of the rest of the country that has different gas formulations for each geographical area and elevation and season as mrtexas said. I thought his response was very appropriate and helpful and other's response to his not so.

[Ol' Ron]

I hope you don't use a gas stove to boil the gas, we need you.

[ford38v8]

My apologies to everyone who misunderstood my post. I do have a habit of not making my point clear. I'll try to rephrase it here:

GM was not boiling gas and testing gas, he was conducting tests with methods of preventing gas from boiling in our carburetors and fuel pumps. To this end, he needed to conduct his tests with the same conditions, same gas, same temperature, same flathead, and discovered he now has different gas than he started with for the testing.

GM is trying to somehow make this modern fuel work for the hobby, and for a Exxon Chemical Engineer to come along using his high falootin' words telling us not to worry, eveything is under control, and for him to play dumb about why GM is conducting his tests just hit me wrong. Perhaps Mr Texas misunderstood GM's purpose, and perhaps I misunderstood Mr Texas. Miscomunications all around, my apologies for that.

My rant is not about the price of gas either. My rant is about force feeding the American Public on CORN in every way and every form possible, and telling us it's for our own good. Ethanol is the problem, we need to open our eyes to that fact and get back to distilling Corn Liqueur and get it out of our gas tanks.

[Seth Swoboda]

"My rant is about force feeding the American Public on CORN in every way and every form possible, and telling us it's for our own good. Ethanol is the problem, we need to open our eyes to that fact and get back to distilling Corn Liqueur and get it out of our gas tanks."

Off topic and not really early ford related but hey, I will agree with the quoted statment above.

[STEVE O]

I have another question to throw out. I am told by the tanker driver that at the terminal where he picks the fuel up that the ethanol is then added onto the tank after our so called pure gas is loaded. Here in this part of Virginia it is very hard to find places that have pure gas with no ethanol. Thanks to everyone for all the tests on our old cars because as always we'll have to find a way to deal with it. Steve

[mrtexas]

Originally Posted by STEVE O

I have another question to throw out. I am told by the tanker driver that at the terminal where he picks the fuel up that the ethanol is then added onto the tank after our so called pure gas is loaded. Here in this part of Virginia it is very hard to find places that have pure gas with no ethanol. Thanks to everyone for all the tests on our old cars because as always we'll have to find a way to deal with it. Steve

I apologize if I came across as a smart-a@@. Whether gasoline boils in your carburetor is a complicated problem.

Yes, you are correct. The gasoline is called RBOB (Reformulated Blendstock for Oxygenate Blending) that is blended at the refinery without ethanol. It is also low in octane so that after the ethanol is added it is correct.

The reason ethanol is not blended at the refinery is that it picks up water very easily and turns milky. Not many want to buy milky gasoline. So the ehtanol is added closer to the gas station at the terminal.

[mrtexas]

Originally Posted by STEVE O

I have another question to throw out. I am told by the tanker driver that at the terminal where he picks the fuel up that the ethanol is then added onto the tank after our so called pure gas is loaded. Here in this part of Virginia it is very hard to find places that have pure gas with no ethanol. Thanks to everyone for all the tests on our old cars because as always we'll have to find a way to deal with it. Steve

I apologize if I came across as a smart-a@@. Whether gasoline boils in your carburetor is a complicated problem.

Yes, you are correct. The gasoline is called RBOB (Reformulated Blendstock for Oxygenate Blending) that is blended at the refinery without ethanol. It is also low in octane so that after the ethanol is added it is correct.

The reason ethanol is not blended at the refinery is that it picks up water very easily and turns milky. Not many want to buy milky gasoline. So the ethanol is added closer to the gas station at the terminal.

[Old Henry]

BUBBA'S IGNITION just posted this thread with a link to the latest info on gasoline that probably tells all of us more than we'd ever want to know about the subject. If anyone is really interested in the "classes of gas" and beyond this is a definitive authority. https://www.fordbarn.com/forum/showthread.php?t=65180

[G.M.]

The reason I'm testing was to track down the problem brought up many times of gas leakng out of the carb when the engine is shut off hot. I also encountered vapor lock problems in the past few years which I never had in over 30 years. After doing all the test drives in 84 to 85 outside temperatures every time I tested with the same 10% ethanol gas. First I would see one small bubble in the glass pump filter bowl and as it got hotter more bubbles and a half inch of fuel missing in the glass bowl. Heat in the rear of the engine gets the firewall of the 39 125 or more in the area of the fire wall clamp that clamps the metal fuel line from the tank to the fire wall heating the fuel in the line close to 125. Even with the clamp removed and the line pulled out 2"s from the firewall with insulation over the fuel line the heat was radiated to the brass flex line fittings on both ends, fuel line and pump ends. I moved the fuel line well clear of the exhaust system and the line is cool where it drops down to the frame and back to the tank. I looked at the temperature on the thumb nut and little cup under the gas bowl and that gets to 125. This is where the where the bubbles come from in the fuel bowl. If you think of it bubbles don't come from the top they are caused by the cup and thumb nut plus the wire bale. With Bob Shewmans 1/2" vented spacer under the carb and the heat riser holes reduced to 1/4" THERE IS NO HEAT issue with the gas from heat from the carb. The intake manifold below the insulted spacer is 155 and the base of the carb 98 to 102. It looks to me like the carb fuel bowl temp should be kept in the 110 to 114 degree range. With the reduced heat risers and insulated spacer the only source of hot gas in the carb is hot gas comming from the fuel pump. I put a 1" insulated spacer under the fuel pump with a 1"longer push rod giving me 1 3/4" clearance between the 155 degree intake manifold and the bottom of the fuel pump. This helped a little but the pump was still getting 125, providing 125 degree gas to the carb fuel bowl. The carb itself disperses a little of the heat from the 125 gas and I see 118 to 120 on the bowl after driving. Now when the engine is shut down at 180-185 water temperature the heat builds up in the engine compartment, the gas in the fuel bowl gets over 125 and boils in the carb and the gas in the glass bowl is 1/2" low. When this gas gets hot the fuel pressure drops and jumps up and down on the gauge. This makes hard starting and loss of power until cooler gas is run through the pump and carb until the carb cools down in the 115 range and the pump below 120. Running at 55 MPH runs enough fuel through everthing to keep it cool. I insulated the fuel line with a foam type cover from below the firewall up over the flex hose fitting on the pump. This combined with the raised pump made a noticeable improvement. Over the weekend I made a loose insulater for under the pump, behind the pump and up the firewall about 3". Drove it yesterday and it was 83 but didn't feel that hot so I didn't bother to much with temperatures. It was 84 today and did a lot of city driving stopping several times for 10 or 15 minutes. It started right up every time and ran smooth.

Tried a 12 volt muffin fan running on 6 volts
Temperatures when we returned just laying on top of fuel pump for 10 minutes
Left head 180 right head 181 Right head 183 left head 184
cab bowl 118 carb bowl 112
fuel pump inlet 122 fuel pump inlet 114
fuel pump 123 fuel pump 118
glass bowl thumb screw 127 glass bowl thumb screw 115
carb base 102 carb base 100
intake maniflod below spacer 155 intake below spacer 158
fuel pressure 1 1/2 psi jumping up and down fuel pressure 2 psi steady

Notice the fuel temperature drop with a very small amout of air blowing on
the pump. Also notice the fuel pressure rises and smooths out as the temperature
of the fuel in the pump cools.

Let it run another 5 minutes with the fan that is just blowing a light amount of air and the pump and fuel temperatures continued to come down. These are the temperatures when I shut down. Notice that the engine temperature is going up but with the fan the fuel temperature is going down and the fuel pressure is still going up.
Right head 186 left head 185
fuel pressure 2 1/2 psi
fuel inlet 112
fuel pump 113
carb bowl 108
carb base 97
glass bowl thumb screw 114 (still picking up heat from engine)

I found a shorter glass bowl and bale. I'm going to try it which will raise the thumb screw up 1" from further the heat. A pump without the filter would not get as hot but I want the filter. An electric pump not going through the mechnical pump would also work but I don't want an electric pump. After shut down with Bobs [email protected] flex hose with the check valve the fuel pressure held at 1 lb for 3 minutes and held at 3/4 lb for 5 minutes and I went home. G.M.

[ford38v8]

George, thank you, very useful information. I hadn't thought that the pump would get that hot, but now we know the reality of vapor lock!

[barryfromvictoria]

G.M. ---Keep up the good work . Me and a lot of barners are very interested in your experiments and letting us know your progress. Thanks for sharing----Barry