The Y Files

Question how do the petroleum products differ and what is vapour pressure requirement? We bits just use the same fuel all year. How does the fuel affect the cars engine? When is the change over supposed to take place and does any one check up on this. Suppose you fill up a few days prior to the change then have to fly off for a while what happens to the old fuel you haven't used? I know just too many things to deal with. Sorry for my asking but I would like to know.

Gasoline with a higher vapor-pressure is better for starting your car on cold winter mornings. These winter blends evaporate more quickly on hot days, however, and (according to the EPA) serve to increase smog levels in major cities. The change-over from winter to summer fuels takes place at different times across the U.S. For example, because spring comes earlier to Georgia than to New York, drivers in Atlanta begin to use summer blends before motorists in Manhattan do. I'm not sure of the exact switch-over dates, but I think that the U.S. is divided into zones. As for the matter of enforcement, there's probably paperwork that service stations and distributors need to file with regulatory agencies. Hope this helps.

I expect some one will come forward with more info, thank you Moose.

Moose,

E10 is still voluntary here and I notice it is much easier to fill the tank with E10 than normal 91 unleaded because of less kickback (11dec C is a cold day though, temps are more often 20 to 35). That indicates to me a lower vapour pressure for ethanol. How do you manage with winter / summer blends for diesel? Summer blends here can make winter starting impossible due to gelling at around 10 deg C (it comes good at around 9.00am).

Hello Emjay4119,

In North America, refineries also supply seasonally-adjusted diesel fuels during the winter months. Gelling remains a risk, however, especially when there are colder-than-predicted temperatures. Some drivers add an antigel or anti-gelling agent. In the case of truck stops and wholesale fuel suppliers, a common practice is to blend a lighter diesel stock (No. 1) into the regular No. 2 fuel.

Hope this helps.

Moose

Steve,

Thanks for the info, it sounds rather involved with your low temperatures. In 2000 we had a longer than usual wet season, which meant the sugar industry used less diesel ,so some summer stock was left over (especially at Mobil) then the winter was cool (Minimums down to frost foint for a few hours around daylight) and this was enough to create merry hell.

Do any American diesel vehicles have fuel preheaters to compensate for cold conditions?

They sure do, Emjay4119. Here's a link to a description of a diesel-fuel preheater that wraps around the filter housing. I haven't purchased anything like this myself, but I'm toying with the idea of buying a Volkswagen Diesel four-wheel drive before the snow flies again. (The gas mileage is great.) If I take the diesel route, I'll either have to build a garage to keep my car warm or install a preheater. The preheater would be cheaper!

So the problem with this guy Routt's argument is that he makes it sound like everyone has to changeover at the same time. If Moose is right, then there would be competition for gas (and higher prices) in a specific zone, but not across the country all at the same time.

The shortage of refineries is a HOAX ...they use this tired old excuse every time and sell and sell and repeat and repeat it every time they multiply the monoply they have on the gas.... it's a lie pass it on ... they all sit on each other's boards and tell the same old story ...and also they burn the refineries intentionaly ...the old ones... check out the news stories over the past few years ...do the research.. they get the insurance... keep the refineries down to a below adequate value and then HOAX it to the stupid gullible public .... expose them please ...pass it on

Truth

C'mon back to CR4 and check out Part 2 of this story, Guest. There's a section called "America's Refinery Capacity" that you'll find to be of interest.