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Old 12-25-2020, 12:54 PM
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Tom Vaught Tom Vaught is offline
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Join Date: Dec 2001
Location: The United States of America
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Quote:
Originally Posted by Joel Koontz View Post
I got a portable inverter generator a few years ago. Works very well and always starts within 2 pulls(usually 1) on FRESH gas. There have been times when I have let the gas get 2-3 months old and then tried to start it. Would not start, even with many pulls, different choke settings etc.

Drain the old gas, put in fresh and it starts on first pull.

Same scenario, at least 3 times now so I am certain that the gas is degrading and some of the vapors that were present when it was fresh, are no longer there, after it has set for 2-3 months.

NOTE: This degradation may not occur as rapidly in a modern "sealed" fuel system, where "there is no place for the vapors to go" and the effect is probably minimized by a FI system that atomizes the fuel much better, but in old stuff it is a major issue.
I used to fill up a couple of the Red Automotive 'round' gas cans with fuel for my lawn tractor. Over a period of time my John Deere Tractor would exhibit longer crank times before firing or not fire at all even with different choke settings (Hand Choke) on the mower.

I gave away the automotive cans and the one boat gas can and bought 3 of the military fuel cans with the hinge locking cap. Very good seal on this military can.

Now I can fill them a couple of times a summer and when I add new fresh gas from the can the tractor always fires off and runs well immediately with only a few seconds of the choke applied.

So a big issue with today's gas, as suntuned mentioned is the vapor pressure loss in the bowls of typical carburetors. The fuel is part of it, but the other part is the open vented carbs do not do well with storage, limited driving, and today's alcohol blended fuels.

Tom V.

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