What's the difference between winter & summer fuel?

[stumpfield]

Both gasoline and diesel... Anyone know the differences? Which Gasoline is better for small engine? I mean will stay fresh longer for occasional use gas powered tools. The gas station here is about to swith over from winter to summer fuel. I don't if I should fill my tanks now or wait for the summer fuel.

 

[thatguy]

Gas - Summer gas is more oxygenated than winter gas due to EPA regulations for cleaner air.. Also keep in mind you have 'country' and 'city' gas - City gas is reformulated (RFG) for cleaner air... Some areas such as Chicago have around 12 different varieties of RFG - which can only cause the manufacturing price to increase greatly

Diesel - Winter diesel is a mixture of diesel and kerosene to lower the waxing point of the parafins in the fuel.. Around here the mix is about 80% dsl and 20% kero

Brian

 

[CurlyDave]

Gas: In addition to oxygen, summer gas has "heavier" components, so the vapor pressure is about the same in summer as winter gas "lighter" components in the winter. Essentially, in order to start the engine you want the right percentage of gas vapors in the gas/air mix.

Diesel: 20 years ago when I worked in this area, the right terminology was "cloud point". As temperature is lowered, wax crystals form in the fuel and it starts to look cloudy. The wax burns just fine if it is dissolved in the fuel, and actually has more energy. The problem is that it will clog the fuel filter.

Winter blends have less wax, and a lower cloud point.

If I had to use only one fuel year round, I would pick winter fuel in both cases, because it will start easier.

Neither winter or summer gas will stay fresh for a whole season, much less a year. I always add Stabil. Most of the time I add twice what they say to add. I would much rather spend a few bucks on gas stabilizer than spend 20 minutes trying to start a reluctant small engine.

The only diesel additive worth using is something to prevent algae in stored fuel. I have been to the research departments at Mack, Cummins, Caterpillar, and Yellow Freight, and they all agreed on that issue.

 

[smfcpacfp]

Winter gasoline has more butane in it to make it start easier in cold weather. It does not have as much energy as gasoline which is one of the reasons why your mileage is worse in the winter.

"Winter" diesel is just a blend of #1 and #2 diesel, at least where I live. Now you generally find #1 and #2 as choices. Many years ago you just had one diesel pump and they changed the mixture when the weather turned cold. I imagine in the summer it was just #2.

 

[LBrown59]

I don't need # 1 winter blend diesel unless the temperature is below 14 degrees.
Since we have few if any days that cold in the winter time I could probably get by with #2 summer blend diesel the year round.
== L B ==

 

[4720 OWNER]

Currently about $1 or more a gallon. This bites!!

 

[LBrown59]

Currently about $1 or more a gallon. This bites!!

which one is a dollar more.
This seems very odd as i've never been to a station where they offered winter and summer both at the same time.
Do they have seperate pumps for each one marked with different prices on the pumps?

 

[4720 OWNER]

Only buy a couple times a year and the fall/winter is usually a lot cheaper than the spring/summer.

 

[Tom_H]

Currently about $1 or more a gallon. This bites!!

which one is a dollar more.
This seems very odd as i've never been to a station where they offered winter and summer both at the same time.
Do they have seperate pumps for each one marked with different prices on the pumps?

He may have been doing a play on the word "difference", which is what you call the answer in a subtraction problem. It "bites" that we seem to be paying a dollar more in summer than we do in winter. This yo-yo thing with fuel prices does bite. My fear is that it's going to quit going up and down and go nowhere but up. I read an article in which the writer hypothesized that the same people who invested in mortgage companies for a quick profit, rode that wave until the bubble burst and their massive investment into energy stocks nowadays is part of what is inflating fuel prices. He thinks when the prices of fuel "bubble" to a high point, they'll cash in for their quick profit and the bubble will burst.

I have no idea how much truth there is in that, but it surely does seem that every time one of these economic messes happens, there is somebody already rich at the top of the food chain who somehow just gets richer because of it all.

It seems like the price of everything is really going up, fuel, groceries, etc. The only things going down seem to be the cost of houses and salaries. "Bites" is a pretty appropriate way to describe it.

 

[Pilot]

FWIW, the fuels expert at the Experimental Aircraft Association says that in Florida and similar climates, yes, you do need to add Stabil, but in cooler, drier climates gas will keep longer and he guessed as much as a year in western Oregon. Makes sense, as deterioration is likely a chemical reaction. And I have had no problems with gas as much as 6 months old, but have not tested the 1 year theory.