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Semi-old gas? by Doggo
Started on: 04-01-2025 06:48 PM
Replies: 18 (188 views)
Last post by: sleek fiero on 04-02-2025 09:01 PM
Doggo
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Report this Post04-01-2025 06:48 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hey hey! So about August of last year, I filled my girl up to the brim with low quality gasoline because obviously I’m going to use it all, right? It’s not like the car is going to sit in my driveway for nine months without moving (much). Well here we are nine months later. She’s been sitting since about August in my driveway through the Chicago winter, which granted wasn’t terrible this year. It runs, we pull it in and out of the garage and I make sure to let her run for 15ish minutes every few weeks. So far no issues. My question is, should I anticipate future fuel system issues? I don’t know exactly how gas turns to varnish. Once the tank starts to empty and it starts sucking up the crud that settles at the bottom will that be an issue? I just don’t want to be caught with a clogged fuel pump while out and about.
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Dennis LaGrua
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Report this Post04-01-2025 07:31 PM Click Here to See the Profile for Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
On hobby cars its common to have aging gasoline in the tank. I only use my Fiero's in late spring, summer and early fall. There is always leftover gas in the tank at the end of the season when my car goes into storage. I solved the issue by using Stabil gas preservative in my gas, keep the tank full and have never had a problem. Not that I would recommend it but a friend of mine had gas with Stabil in his car for 12 years. He put in a new battery and it started right up. That sold me on the product.

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olejoedad
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Report this Post04-01-2025 07:51 PM Click Here to See the Profile for olejoedadSend a Private Message to olejoedadEdit/Delete MessageReply w/QuoteDirect Link to This Post
There is no need to add a stabilizer to the gas on a car that is sitting for the winter.
I've had cars sit for 3 years and they fire right up and run just fine - no fuel stabilizer.

Save your money.
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82-T/A [At Work]
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Report this Post04-01-2025 08:40 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Doggo:

Hey hey! So about August of last year, I filled my girl up to the brim with low quality gasoline because obviously I’m going to use it all, right? It’s not like the car is going to sit in my driveway for nine months without moving (much). Well here we are nine months later. She’s been sitting since about August in my driveway through the Chicago winter, which granted wasn’t terrible this year. It runs, we pull it in and out of the garage and I make sure to let her run for 15ish minutes every few weeks. So far no issues. My question is, should I anticipate future fuel system issues? I don’t know exactly how gas turns to varnish. Once the tank starts to empty and it starts sucking up the crud that settles at the bottom will that be an issue? I just don’t want to be caught with a clogged fuel pump while out and about.



I would just fill it up with fresh fuel when you start driving it around again. The new fuel and old fuel will mix and delute the bad...
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Doggo
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Report this Post04-01-2025 10:49 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 82-T/A [At Work]:
I would just fill it up with fresh fuel when you start driving it around again.


That’s what I was thinking… my buddy wants to siphon it all out. Miscellaneous running has burned about half the tank if the gas gauge is to be believed. So probably enough to mix well with good gas. Then it’s off to the car wash to shoot it with pressure washers!
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Doggo
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Report this Post04-01-2025 11:00 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post

Doggo

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quote
Originally posted by olejoedad:

I've had cars sit for 3 years and they fire right up and run just fine - no fuel stabilizer.

Save your money.


I remember hearing somewhere that bad gas is worse for carburetors than injection systems, does that sound right?
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cartercarbaficionado
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Report this Post04-01-2025 11:06 PM Click Here to See the Profile for cartercarbaficionadoSend a Private Message to cartercarbaficionadoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by Doggo:


I remember hearing somewhere that bad gas is worse for carburetors than injection systems, does that sound right?

it is true to a point. it depends on the injectors and how bad the fuel filters are. usually what REALLY hates old gas thats starting to get sticky is any motor with a pushrod. if its like 5 year old gas maybe throw 2 stroke in to prime it to help lube it after you change most of it.
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Doggo
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Report this Post04-01-2025 11:08 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dennis LaGrua:

but a friend of mine had gas with Stabil in his car for 12 years. He put in a new battery and it started right up. That sold me on the product.



12 years is quite a while. Do you know what car it was? I wonder if there’s anything with the design of that cars fuel system that makes it less likely to get gummed up with old gas or something. Storage environment probably plays a large role in it. I imagine this vehicle was garage kept?
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Report this Post04-01-2025 11:11 PM Click Here to See the Profile for buddycraiggSend a Private Message to buddycraiggEdit/Delete MessageReply w/QuoteDirect Link to This Post
I had a car with a carb sit at a body shop for almost 2 years while he took his freaking time doing a little body work and paint.
I had to clean the carb, but it had no problem burning the gas.

I think you'll be fine.
At most, maybe throw in a bottle of HEET to absorb the water that may have happened from condensation.

[This message has been edited by buddycraigg (edited 04-02-2025).]

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Patrick
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Report this Post04-01-2025 11:54 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post

Gas quality may be different with today's fuels, but in the early 2000's I resurrected my '84 that had been sitting for eight years. I simply added fresh fuel to the old stinky stuff, and it ran just fine. YMMV
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sleek fiero
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Report this Post04-02-2025 10:49 AM Click Here to See the Profile for sleek fieroSend a Private Message to sleek fieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
A year is not a problem. Best way to put away is with the tank full so little air (oxygen) in tank to spoil fuel. Best way for multi year long term is to drain system and start and run dry.so no fuel in tank ,lines, or injectors to go bad. Fuel stabilizer is good short term but is not effective long term. Our fuels now a days has methanol in it and will cause severe corrosion if it goes bad from age. Methanol is a moisture attractant. sleek
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Report this Post04-02-2025 11:14 AM Click Here to See the Profile for Vintage-NutSend a Private Message to Vintage-NutEdit/Delete MessageReply w/QuoteDirect Link to This Post
Gasoline lasts about 3 to 6 months in the tank
Adding a fuel stabilizer to fresh gasoline will extend its life to around 2 years
{A fuel stabilizer will NOT help aged gas}

For the most part, aged gas just loses some of its ability to combust and tiny engines suffers more than bigger engines
The best way to make aged fuel usable again is to dilute it with fresh gasoline

 
quote
bad gas is worse for carburetors than injection systems, does that sound right?

Aged gasoline 'thickens' in a carburetor and forms varnish-like substances which will clog the tiny fuel pathways so to me, yes - it is worst
{I always treat carburetor vehicles with fresh gasoline with a stabilizer before storage}

The biggest problem of 'semi-gas' is moisture {aka water} and especially with fuels with ethanol.

Like brake fluid, ethanol is hygroscopic, which means it attracts and absorbs water molecules from the surrounding atmosphere.

Moisture contamination leads to corrosion or ‘rusting’ of metal components; especially the fuel tank....

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1985 Fiero GT
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Report this Post04-02-2025 12:19 PM Click Here to See the Profile for 1985 Fiero GTSend a Private Message to 1985 Fiero GTEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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Originally posted by sleek fiero:

Our fuels now a days has methanol in it and will cause severe corrosion if it goes bad from age. Methanol is a moisture attractant. sleek


As far as I know, it's ethanol not methanol, maybe they put a little methanol in to, but it isn't enough to matter, they commonly use 10% ethanol.
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Doggo
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Report this Post04-02-2025 05:32 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sleek fiero:

Best way to put away is with the tank full so little air (oxygen) in tank to spoil fuel.


Wow I accidentally did it right? Cool!
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Doggo
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Report this Post04-02-2025 05:38 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post

Doggo

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quote
Originally posted by Vintage-Nut:

tiny engines suffers more than bigger engines



By ‘tiny’ engines you mean like small engines, right? (Lawnmower, snowblower) not like a tiny 4 cyl vs a bigger v8
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Doggo
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Report this Post04-02-2025 05:40 PM Click Here to See the Profile for DoggoSend a Private Message to DoggoEdit/Delete MessageReply w/QuoteDirect Link to This Post

Doggo

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quote
Originally posted by Patrick:


but in the early 2000's I resurrected my '84 that had been sitting for eight years. I simply added fresh fuel to the old stinky stuff, and it ran just fine. YMMV


What kind of environment was the car left in? Garage? Field? Exposed to elements? I’m curious
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Patrick
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Report this Post04-02-2025 06:00 PM Click Here to See the Profile for PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Doggo:

What kind of environment was the car left in? Garage? Field? Exposed to elements?


Garage? Ha, I wish! It sat out in the open in my backyard.

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Report this Post04-02-2025 07:13 PM Click Here to See the Profile for Vintage-NutSend a Private Message to Vintage-NutEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
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By ‘tiny’ engines you mean like small engines, right? (Lawnmower, snowblower) not like a tiny 4 cyl vs a bigger v8


You're correct; when I say ‘tiny’ engines, I mean like garden equipment.
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sleek fiero
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Report this Post04-02-2025 09:01 PM Click Here to See the Profile for sleek fieroSend a Private Message to sleek fieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes Vintage I meant ethanol Not methanol comes in most pump fuels now. But methanol (methall hydrate) is used to soak up water and burn off as you run your car. It will also cause corrosion. BTW fuel including diesel will start going stale before you even buy it.. Stabilizer certainly will help but old fuels do rot senders ,hoses, tanks and pressure regulators.
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