Gas stabilizer

Maintenance advice to keep your Spider in shape.
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PaulC
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Your car is a: 1979 Fiat Spider 2000
Location: Maine

Gas stabilizer

Post by PaulC »

Any opinions on Stabil or Seafoam for a gas treatment ?
Spider gets used once a week or so now that winter is coming to northern AZ.
Or is it even necessary?
18Fiatsandcounting
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Joined: Fri Mar 15, 2019 11:23 pm
Your car is a: 1969 and 1971 124 spiders
Location: San Francisco Bay Area

Re: Gas stabilizer

Post by 18Fiatsandcounting »

Opinions may vary, but mine is that once a week should be fine without a gas stabilizer. I'm going to assume you're driving 10-20 miles per trip, so maybe a few months until you have to refill the tank? I've never noticed an issue with gas going bad until you measure the time between fill-ups in years, not months. And, given the cold temperatures, I would think that any chemical degradation that might be occurring would be slower.

And, while I am not a shill for Seafoam, it did seem to help me pass my last smog test on my '93 Jag. Before the test, I disconnected a vacuum port on the intake and (slowly! carefully!) sucked a can of Seafoam into the engine. Passed the smog test with flying colors, as compared to previous years which were always right on the edge of failing. Normally I view these various engine "ointments" as just another version of snake oil, but in this case it seemed to work.

-Bryan
PaulC
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Your car is a: 1979 Fiat Spider 2000
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Re: Gas stabilizer

Post by PaulC »

Yep, 10 to 20 miles is about right and a few months for a fillup.
Guess I'm just over thinking it :? .
wetminkey
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Your car is a: 1979 2000 Spider
Location: Ault, Colorado

Re: Gas stabilizer

Post by wetminkey »

As you can see from my list of presently owned vehicles below, I've been storing vehicles full of gasoline, over the winter months, for MANY years now. Covered, but not heated, in Colorado,..And I've done the research on this topic.
Gasoline will start to change in about six months, and alcohol blends absorbing moisture seem to be the problem (but gas has always gotten old, given enough years),...
A "glaze" (or "varnish") will occur in the carburetor passages as the gasoline evaporates, and it will restrict/plug the very small ones. In addition, gasoline that has absorbed moisture degrades in it's ability to ignite.
I use fuel stabilizer in most of my vehicles/tractors, but they may sit idle all winter long,...and in temps to -25, or so max.
I have found that StarTron fuel stabilizer is just as available, and far cheaper than Seafoam, which I used for a long time. StarTron is 1oz/ 8 gallon as opposed to 1oz/gallon, and cheaper per the oz.
Once a week, in Arizona, should be enough driving to not need stabilizer, Paul.
I do not know if it's true, but it seems to work for me,...I run high octane in the vehicles that I drive infrequently. Even my '72 SuperBeetle. I think the the higher octane gas usually has less methanol added to it,...due to it's ability to burn better. And, therefore, absorbs less moisture than methanol blends.
I find that fuel injection is affected less than carburetors are, and newer carbs are affected more than old carburetors (generally due to smaller passages, that plug easier).
A good point, however, is that the fuel stabilizers also clean the components of the fuel system,...and can help to remove any "varnish",...so adding them, or a carb/fuel injector cleaner occasionally, is a good idea.
I think that sums up what I've learned,...I hope it helps! Good info for a lot of folks with cars, I guess,...
Todd.
1988 Mazda RX-7
1979 Fiat Spider 2000
1978 3/4 ton Chev 4x4 P/U "FRANKENTRUCK"
1976 Camaro
1972 VW Superbeetle
1969 Ford F100
1968 Mustang coupe
DieselSpider
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Joined: Wed Dec 24, 2014 10:21 pm
Your car is a: 1978 124 Spider with Isuzu Turbo Diesel

Re: Gas stabilizer

Post by DieselSpider »

Arizona is usually pretty dry so you probably have littlle worry as far as ethanol absorbing humidity from the bowl or fuel tank vent however treating each tank with StarTron to stabilize it against any chance of condensation issues would do no harm.

If you stabilize fresh fuel then you are good for up to 2 years just in case something happens and you do not use up that tank of fuel well before then. Once fuel starts to degrade then its really too late for stabilizing it and you can be facing polishing and mixing it with fresh or paying to have it disposed of.
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AndyVAS
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Re: Gas stabilizer

Post by AndyVAS »

Some of the fuel stabilizers have a little measuring thing made into their jug. Using that you can throw in a splash every time you fill up. I'm aware that automotive fuel is supposed to be good for 6 months or so but I have had issues with it after just 2 months. Play it safe and top off with premium grade and stabilizer before you let it sit of any extended time. An extra $10 is better than rebuilding the fuel system or cracking a piston from detonation.
Andy Phillips
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DieselSpider
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Your car is a: 1978 124 Spider with Isuzu Turbo Diesel

Re: Gas stabilizer

Post by DieselSpider »

AndyVAS wrote:Some of the fuel stabilizers have a little measuring thing made into their jug. Using that you can throw in a splash every time you fill up. I'm aware that automotive fuel is supposed to be good for 6 months or so but I have had issues with it after just 2 months. Play it safe and top off with premium grade and stabilizer before you let it sit of any extended time. An extra $10 is better than rebuilding the fuel system or cracking a piston from detonation.
Indeed some stations do get their fuel at times from scavengers who pump out the dregs from the fuel depots and polish it up a bit however it may already be over a year old by that time. Also premium fuel from a low volume station that does not sell much premium can likewise be very old and already starting towards phase separation by the time it gets pumped into your tank.

Better safe than that other thing.
PaulC
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Your car is a: 1979 Fiat Spider 2000
Location: Maine

Re: Gas stabilizer

Post by PaulC »

Already use premium as that's what the owners manual and workshop manual specified, so it looks like a jigger of Startron would be all I need.
I know when we first got the car, I pumped out the gas that was.in it as I was.having problems getting it started.
What came out bore little resemblance to gasoline both in color and odor. Looked like it reverted back to dino pee.
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