On 5/24/96 Melissa Mann wrote:
>As many of you know, California has recently switched to the new gasoline.
I think some of the other states have been using this new gas as well.
>I was wondering if anyone on the list has noticed any differences with the
new gas -- in performance, gas mileage, etc. Also, has anyone gotten a fuel
leak?
>I'm especially interested, because I have quite the fuel leak. I noticed it
today on my way back from lunch. Let's just say that I'm really glad I don't
smoke! I can also attest to the fact that the new gas smells quite a bit
different than the old stuff.
>New gas, new fuel leak...coincidence? I think not (but I don't want to jump
to conclusions.)
>Anyone else?
>-- Melissa (gas is not getting to the carb., so I reckon I'll be walking
home tonight!)
Yep! Definitely got some info and opinions. The stuff is called "oxygenated
gasoline", and its supposed to help reduce certain polutants coming from the
tailpipe. I hear a lot of rumors that it does do that, but in fact may
produce some other noxious by-products in the process. And California is not
alone. Since the Chicago area exceeded cretain federal guidlines for air
polution in the winter of '94-'95, Cook county and the six surrounding
counties are now required to use this type of fuel, at least in the winter
months.
When it comes to making this fuel, there's more than one way to skin a cat.
In its better form the stuff is a lot like normal gasoline, but contains
some additional things like iso-butanes, and costs 5% to 10% more to produce.
Your car probably won't notice the difference.
Another way to produce a similar effect that meets the requirements for
emmissions is to add alcohol (does the term "gasohol" sound familiar?). This
form of the fuel is easily identified at the pump by the pump sticker stating
"Contains 10% alcohol". It's usually Ethanol, which is preferable, but it
can be Methanol, which is a bit more noxious and harder on the rubber bits.
Also bear in mind that alcohol contains just about half the energy per
gallon as gasoline. If you have been using non-alcohol bearing fuel and then
switch to a fuel with 10% alcohol, you may expect a 5% decrease in fuel
mileage. If the fuel is otherwise acceptable to you, you should at least
look to pay 5% less for the gasohol. Gasohol should actually be less
expensive at the pump, because the alcohol content does not carry the burden
of federal gas tax. But don't expect a big price break. It has been my
experience that it is usually only reduced about two cents a gallon, if any
at all.
Personnaly, I go to great lengths to avoid the alcohol bearing fuels, for
more than one reason. In 1989 I did a "no-lead" head job on my MGA, because
leaded gas is nearly impossible to find any more. I then started using the
gasohol because for the same price you get about two points higher octane
rating. So far, so good. But then for a time I had installed an aftermarket
fuel pump that had a natural rubber diaphram. The diaphram failed in just
three weeks of use. I installed an identical replacement obtained for free
under warrantee, and that one also failed in three weeks. When I opened it
up I found the diaphram had turned to mush, obviously dissolved by the
alcohol. I now use a pump with no natural rubber parts, and have had no more
problems (yet). But I suspect that the alcohol bearing fuels also attact any
other natural rubber parts in the fuel system, including hoses and rubber
grommets around the carb float chambers.
Another potential problem with gasohol is that the alcohol in the fuel boils
(or vaporizes) at a lower temperature than regular gasoline. In my MGA this
causes nasty vapor lock problems in hot weather. This car has just one fuel
line going to the carbs, with no return line to the tank. When the engine is
hot, and I shut it off and let it set for a few minutes, then start it up
again, it coughs and sputters until it gets some cool fuel into the carbs.
Slightly newer cars with a sealed fuel system have two lines to the carbs,
one to supply fuel, and one as a vent to the fuel tank and carbon canister.
These models may still be suseptable to the same problem.
Much newer models with feed-back carburetors or fuel injection systems
usually have three lines to the throttle body or injector system. One line
supplies fuel, one line is the vent, and the third line is a fuel return line
back to the fuel tank. These systems continuously recirculate extra fuel
back into the tank, thereby supplying cool fuel to the engine at all times.
Expect no vapor lock problems with this set up.
I hereby disavow any further knowledge about gasoline.
Barney Gaylord -- 1958 MGA
Naperville, Illinois
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