Dad worked for Esso, 40 years. 

All gas is not equal and one does not require a high performance rig to be affected by cheap gas. 
One does not have to always use the expensive stuff, but an occasional run through of the expensive stuff will have an effect.

To further the analogy, I don't drive a Labourghini.  I drive a 10 year old Pontiac.  It failed a required emissions test.  I bought a mickey of engine cleaner (Guanteed Pass) and followed the instructions.  Passed the emissions test.

Gas degrades over time.  Last year's cheap fuel may cause more gunk to build up than a new can of cheap fuel.


The real answer here is to get a Trangia and avoid the whole issue completely.   

Thanks Joe,
So I can continue to use unleaded in my stove as I have done for 10 years.  Using about 4 quarts per year.  Oh, my stove is a 35 years old coleman two burner.  Kind of heavy and bulky, but works great.  We generally base camp so weight is less of an issue.  Any gas I don't use on a trip, I put in my van's tank.  Never a problem with old fuel.
Westwood

In the cozies thread, Preacher linked to Zen Stoves. Here's a page from the site on stove fuels if it helps. (You need to Login or Register to view media files and links)

On my last trip I was using three a (possibly four) year old gallon of Coleman. Maybe my stove needs some attention but I had to pump it a lot during cooking. I still have two pints left so I'm kinda hoping it was the stove.

For those who burn unleaded. Does it smell much?

"Coleman fuel has an octane rating of 50 to 55 and none of the additives found in modern gasoline.[2] It has a lower molecular weight than gasoline, kerosene and diesel fuel and cannot be used as a substitute for any of those fuels in modern engines.[2]

The flammability of Coleman Fuel is similar to gasoline; however, it should never be used in modern era gasoline engines. Its high heat of combustion and lack of octane boosting additives like tetra-ethyl lead will destroy engine valves, and its low octane rating would produce knocking.[2]"

reference [2] above = see below
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(see #2 for Coleman's opinion of hte different fuels)


depending on where you live, you likely get a slightly different blend of gas, and slightly different from each company - i.e. shell vs mobil vs conoco      ---   Here in Colorado, they use alchohol or MTBE for "winter" blends to keep the air cleaner - not sure if MTBE fumes would be particularly good for you, but I'd guess not (most stations use an alchohol mix)  - I would guess that California gas would be different yet with thier more stringent air quality requirements, but maybe not

I have one dual fuel Coleman stove, but I've never run gas station gas in it, always using Coleman Fuel instead, on the assumption that it is "cleaner"

I guess you could think that is just a marketing ploy if you like, or not

Windsailor:

Before I became a paper pusher/talker, I used to be a logger in northern Wisconsin.  While starting a chainsaw in the zero to 20 below range could take more time, once the saw was running I never heard of anyone having trouble with the gas, provided you didn't have water or some other impurity in the gas.  Plus cold weather may decrease your gas mileage, but again I never heard of anyone having trouble driving their motor vehicle in the below zero range.

I have no experience with Coleman fuel in cold weather.
Westwood