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Old Oct 21, 2018 | 05:36 AM
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Default Old gas question

How long can gas sit in a gas tank before it will become no good. I removed the carburetor to rebuild so no gas issue for the carb. I can siphon as much as can be done and fill up with new gas then install the clean carburetor - will this be good enough? Is there something else I’m forgetting?

Thanks,
Rich
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Old Oct 21, 2018 | 09:20 AM
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6 months to a year
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Old Oct 21, 2018 | 10:15 AM
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Originally Posted by Z06LMB
...How long can gas sit in a gas tank before it will become no good...Is there something else I’m forgetting?
How old is the fuel in your tank?
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Old Oct 21, 2018 | 10:23 AM
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Sta-Bil says it keeps gas fresh up to 2 years
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Old Oct 21, 2018 | 10:26 AM
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Originally Posted by Z06LMB
How long can gas sit in a gas tank before it will become no good. I removed the carburetor to rebuild so no gas issue for the carb. I can siphon as much as can be done and fill up with new gas then install the clean carburetor - will this be good enough? Is there something else I’m forgetting?

Thanks,
Rich
I had a bad experience with ethanol fuel in my '71. When I replaced the fuel tank and filled it with fresh non-ethanol fuel, I removed the fuel line at the carburetor and flushed the line while cranking the engine just to be sure. Glad I did, there was still some crappy gas in the fuel line.
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Old Oct 21, 2018 | 10:26 AM
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Originally Posted by Easy Mike
How old is the fuel in your tank?
I‘m not sure, 2 years, I could be wrong with a small chance it’s as much as 3 years, I have to look for some receipts. These days I look at the calendar to celebrate how long I’ve been able to stay out of the hospital - otherwise time seems to fly by faster then I notice.


Rich
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Old Oct 21, 2018 | 10:30 AM
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Originally Posted by 71 Green 454
I had a bad experience with ethanol fuel in my '71. When I replaced the fuel tank and filled it with fresh non-ethanol fuel, I removed the fuel line at the carburetor and flushed the line while cranking the engine just to be sure. Glad I did, there was still some crappy gas in the fuel line.
I wish there was ethanol free gas available near me. I assume they charge a lot more for non ethanol fuel?
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Old Oct 21, 2018 | 10:34 AM
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Originally Posted by Sonny71
Sta-Bil says it keeps gas fresh up to 2 years
I didn’t plan on not driving this car so long so I didn’t use any Sta-Bil.

However, I did use Sta-Bil in my generator and it was bad fuel slightly earlier than 2 years.
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Old Oct 21, 2018 | 10:46 AM
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There are a few websites that list places to buy non ethanol gas in most states. Here in western Colorado several stations sell corn free regular. Currently crap regular seller for $2.95 a gallon. Corn free regular is currently $2.30 to $2.35 a gallon. Thats what I run in my restored 29 Model A.

"These days I look at the calendar to celebrate how long I’ve been able to stay out of the hospital - otherwise time seems to fly by faster then I notice."
Rich, Hang tuff!

Last edited by slammin; Oct 21, 2018 at 10:49 AM.
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Old Oct 21, 2018 | 10:50 AM
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Drain or siphon as much as possible out of the tank, fill with fresh ethanol free gasoline, then pump the lines clear. Use a "sacrificial" small electric fuel pump that's designed to have suction on the inlet, or crank your engine without spark and with fuel line from carb disconnected and put in a drain bucket. Use the old mechanical fuel pump for this operation if you do that. Pump until you have clear, fresh as coming out the line from the pump.

If you have a mechanical fuel pump, replace that as well, after pumping the lines to get fresh new fuel through the lines.

Originally Posted by Z06LMB


I wish there was ethanol free gas available near me. I assume they charge a lot more for non ethanol fuel?
Check http://www.pure-gas.org/ for a listing of stations (mostly) with ethanol free gasoline. Their list is fairly good, but sometimes includes stations which don't have ethanol free (like every QT in our area of Georgia). Ethanol free 87 octane regular is generally a bit more than E10 blend premium around here. Ethanol free 90 or 93 octane can be about a dollar a gallon more than E10 blend premium.

Last edited by C6_Racer_X; Oct 21, 2018 at 10:56 AM.
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Old Oct 21, 2018 | 10:58 AM
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Originally Posted by Z06LMB
...2 years,..a small chance it’s as much as 3 years...
Originally Posted by C6_Racer_X
...Drain or siphon as much as possible out of the tank, fill with fresh...gasoline...
I agree. 2-3 years is getting on the long side. Why take the chance?

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Old Oct 21, 2018 | 03:01 PM
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Here's what happened - 2 years premium -winter blend-

It ATE the expensive foam from my Aeromotive Stealth Phantom fuel system. It turned it to powder...

Brand new tank- you can see the results.

The guys at Aeromotive said they've seen gas even with Stabil do the same thing.

I won't use/store gas for over 6 months now...All my lawn tools- run them till they are out of gas.






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Old Oct 21, 2018 | 03:31 PM
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Get rid of every bit of it you can, as stated better safe then sorry!!!! Bad gas will play havoc with your carb and systems. You will be chasing gremlins for ever!!! Ike
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Old Oct 21, 2018 | 05:33 PM
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Originally Posted by Z06LMB


I wish there was ethanol free gas available near me. I assume they charge a lot more for non ethanol fuel?
non-ethanol has better millage, your better off paying 5% more for 10% better millage

ethanol has almost half the energy of gas, it takes 1.8 gallons of ethanol to equal the same energy potential of a gallon of gas... not to mention the other issues the alcohol causes for our non-ready e85 systems

Last edited by naramlee; Oct 21, 2018 at 05:34 PM.
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Old Oct 21, 2018 | 06:21 PM
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If you “have” an airplane you can get 100LL gas or something similar at your local airport. I mix that with ethenol free no lead super from a gas station where I ride my KTM. The owner of the station also rides so he has a pump for this gas.

i don’t let the gas sit for more than a year.
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Old Oct 21, 2018 | 07:36 PM
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Originally Posted by Nowhere Man
6 months to a year


My brother-in-law does fleet sales of fuel and oil to large business and government entities. He says 6-12 months max for premium, and 4-6 months for regular. In addition to deposits forming from sitting, you also lose octane over time, so 87 octane regular is at greatest risk.

I love to retell the story of two SCCA Ford Fiestas I bought for $400 that had sat for ten years. Started right up, but wouldn't rev over 2000 rpm. Changed EVERYTHING from ignition, carb, filters, fuel pump, etc with NO change. Then one day put in fresh gas (the gas was 10 years old), and they ran like rockets. I pump all the gas at the end of each race season out of my Civic race car, and put in fresh each spring.

Fresh gas is cheap.

Marc in Indy
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Old Oct 21, 2018 | 08:33 PM
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Filling the fuel tank to the top and having it sealed will help storage. Drain the float bowls if you can.I use both Seafoam and Stabil together, it seems to always work. Everything always starts and runs fine after our long winters here in Minnesota, even with the ethanol.

As for the old bad fuel. Myself, I would drain every drop out of the tank so you can see the bottom of it to see if there is rust on deposits in it. Flush the fuel lines and put a new filter in. Wouldn't hurt to put a new carb kit in the carb after sitting that long just to head off any possible problems.

Mike
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Old Oct 22, 2018 | 07:40 PM
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Originally Posted by v2racing
... I would drain every drop out of the tank so you can see the bottom of it to see if there is rust on deposits in it. ...
What if there are?

I've got two (a '73 and the '72 that's in my avatar) that have been sitting for about 9 years.

Actually, after sitting that long, what else should be done to prepare each one to run again (obviously flush coolant, oil and filter change, flush and bleed brake system, and new battery)?

TIA!

Last edited by VCuomo; Oct 22, 2018 at 07:44 PM.
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