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Old 01-05-2025, 06:59 PM   #1
slikside
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Re: Gas shelf life

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Why because Ethanol eats rubber parts ?
My quadrahet get used daily ish and still needs an accelerator pump every 6 months
You can just about eliminate the issue if you get carb parts designed for use with ethanol fuels. Cliffshighperformance.com is one such source for quadrajets. I’m sure there are others as well…
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Old 01-05-2025, 07:02 PM   #2
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Re: Gas shelf life

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You can just about eliminate the issue if you get carb parts designed for use with ethanol fuels. Cliffshighperformance.com is one such source for quadrajets. I’m sure there are others as well…

They all seem to fail.
My holley gets all the neoprene methanol safe parts.
Fails about half as fast
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Old 01-03-2025, 05:32 PM   #3
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Re: Gas shelf life

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If mine sits for a month or more. Have to do power valves and accelerator pumps.
I think it's a California thing contributing...ethanol doesn't age well, and you can't escape it here. But a month seems very short to me. I overhauled my quadrajet about 13 years ago with appropriate parts from Cliff Ruggles High Performance, and my truck can sit a good bit longer than that...now, it will have to crank for a while to get some fuel and compression to my tired old (original) 350, but once it fires the first time, it's running!

My lawnmower is a different animal though. I figured out several years back to never leave gas in the tank. I don't need to use it often, so I only put as much gas in it as I think I'll need, and when I'm done, I let it run itself out of gas (Just don't tell the CARB {California Air Resources Board...so ironic, can't make this stuff up!}). It can be months later before I need it again, but with fresh gas, proper priming and some starting fluid, it'll start on the first pull. If I have old fuel from the mower sitting around, I'll dump it into my truck and burn it. Never a problem there.
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Old 01-03-2025, 07:14 PM   #4
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Re: Gas shelf life

Mine sits for long periods and I generally don't sweat it. Generally it sit's about 1/3 full, so Once I crank it up I'll add a few gallons of fresh. I try to remember to add stabilizer, but frequently don't
When I got it and it was pretty rank, I dumped some Berryman in there to keep the bowl from getting sticky. Smoky, but it seems to manage the dissolved solids OK

One time I got "clever" and sprayed carb cleaner right in the bowl, which immediately distorted the accelerator pump blue seal, so I don't do that anymore.
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Old 01-04-2025, 02:39 AM   #5
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Re: Gas shelf life

Fuel is terrible here.
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Old 01-04-2025, 07:19 PM   #6
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Re: Gas shelf life

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Fuel is terrible here.
Looks like a fair bit of moisture in there
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Old 01-05-2025, 02:11 AM   #7
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Re: Gas shelf life

Central California good fuel, typically shell 91

The ethonal pulls moisture like a sponge
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Old 01-05-2025, 03:43 AM   #8
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Re: Gas shelf life

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Central California good fuel, typically shell 91

The ethonal pulls moisture like a sponge
The water in the fuel comes from condensate on the inside of the tank, not absorption out of the air, so keeping the tank full makes a big difference. I only recently learned this.
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Old 01-05-2025, 12:27 PM   #9
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Re: Gas shelf life

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The water in the fuel comes from condensate on the inside of the tank, not absorption out of the air, so keeping the tank full makes a big difference. I only recently learned this.
Well technically the moisture condensates from the air inside the tank it’s not coming from the gas itself. Vented systems suck and expel atmosphere with temp changes . But yes it’s best to keep it full so less atmosphere is exchanged but there always will be some exchange
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Old 01-05-2025, 05:02 PM   #10
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Re: Gas shelf life

Something had changed dramatically from 1999 when It sat til 2005 when I decided to redo it again.
It ran and drove with a new battery and water bottle worth of gas poured into the carb vent.

Now it doesn't sit over a month without something failing in the fuel system.
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Old 01-06-2025, 07:27 AM   #11
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Re: Gas shelf life

I have a cheap little electric fuel pump with some battery clips I use to pump my stuff out into cans.
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Old 01-07-2025, 02:25 AM   #12
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Re: Gas shelf life

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I have a cheap little electric fuel pump with some battery clips I use to pump my stuff out into cans.
I have something like that. I have a Holley Blue racing pump.
I use it to transfer gas from jerry cans to the gas tank. But I'v also used it to transfer gas from one truck to the other, or to de-gas a fuel tank [to jerry cans] so I could work on the Fuel Level Sender.
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Old 01-06-2025, 05:46 PM   #13
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Re: Gas shelf life

...not uncommon to unmount the tank and slosh marbles or similar around in there to dislodge the accumulated sludge out of the bottom
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Old 01-07-2025, 02:38 AM   #14
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Re: Gas shelf life

Using my Holley Blue fuel pump
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