I recently posted about a clogged idle circuit in my Holley 4175 carb and I posed the same question to Mike of Mike's Carburetor. I told him I hadn't started the car an about seven months while I worked on the timing chain. He wrote back that 7 months was too long and the gas had probably turned to varnish and varnished the inside of the carburetor. I stored the car with ethanol free gas. My question is ; how long does it take gas to turn to varnish? And how often should you start a car over the winter to prevent this? I really don't want to rebuild the carburetor again but Mike claimed that spraying the outside air bleeds would not help. My plan now is to keep driving the car and see if the fresh gas (along with carb cleaner added to the tank) wont help given enough time and driving. Paul
gas turning to varnish
- Thread starter spstan
- Start date
Time? Might vary a bit. You can always remove the gas cap and smell to see if it smells like varnish in there.
In an old Phillips 66 Race Fuel website, several years ago, it stated that their race fuel could last about a year . . . IN the sealed barrel it came in, IF the seal was maintained. Further comments were that the lighter factions of the fuel would evaporate first, which also is where some of the octane enhancers reside.
In a car fuel tank environment, which while "sealed" is not the same as being sealed in a gas drum, the tank is still subjected to temperature swings, which can cause a bit of condensate in the tank, repeat CAN, not will. Which is why many recommend "storing" the car with a full tank of fuel . . . which goes against any fire dept rules for an indoor car show. Either "full" or completely empty, depending upon your preferences.
Enjoy!
CBODY67
In an old Phillips 66 Race Fuel website, several years ago, it stated that their race fuel could last about a year . . . IN the sealed barrel it came in, IF the seal was maintained. Further comments were that the lighter factions of the fuel would evaporate first, which also is where some of the octane enhancers reside.
In a car fuel tank environment, which while "sealed" is not the same as being sealed in a gas drum, the tank is still subjected to temperature swings, which can cause a bit of condensate in the tank, repeat CAN, not will. Which is why many recommend "storing" the car with a full tank of fuel . . . which goes against any fire dept rules for an indoor car show. Either "full" or completely empty, depending upon your preferences.
Enjoy!
CBODY67
If you're going to wait for Stellantis to come out with a viable EV at a decent price, don't hold your breath!
Other than fuels, the more I find out about "old motor oils and old rear axle grease", "oil" is not as universally good forever as we might have suspected.
Enjoy!
CBODY67
if you're storing with eth free, be sure the tank and fuel lines have ZERO ethanol, Meaning if you have been running eth, then you'll have to run probably 2-3 full tanks of eth free fuel to ensure nothing is left.
then, store using Stabil Marine, not the regular red stuff.
then, store using Stabil Marine, not the regular red stuff.
Jakter
Well-Known Member
I thought ethanol-free gas was the end-all for whatever ails a vehicle.
it is, but it must be pure 100% un cut extra virgin squeezed from only the best rocks early in the morning when the dew is fresh.
IMHO, 7 months worth of sitting won't leave enough varnish behind to cause any problems.
I'll agree that 7 month old gas should be considered "old gas", but that would only mean it might not run as well as "fresh gas". My cars sit for 5 or 6 months out of the year and I don't have these problems.
I'll agree that 7 month old gas should be considered "old gas", but that would only mean it might not run as well as "fresh gas". My cars sit for 5 or 6 months out of the year and I don't have these problems.
Unrelated, but interesting none the less. I have a Corvair that i last put fuel in the tank no less than 15 years ago. The car is old obviously, the carbs are new 20 years ago and then bolted on the car and used very few miles ( same gas as today ). I jump started it and it ran a few weeks ago.....started, idled, and revved as it should. I couldnt drive it, but was really amazed the gas had any energy left to give, so to speak. Hats off to Rochester, I guess lol.
So, the varnish part.....the neighborhood stunk to high heaven while the car was running, and the car literally smelled of varnish for days afterwards.
So, the varnish part.....the neighborhood stunk to high heaven while the car was running, and the car literally smelled of varnish for days afterwards.
Just smell it.. It has a very distinct odor and there is no mistaking it for gas. The more varnish, more smell. And even though you can run old gas, I wouldn't. It will leave gummy deposits on valves/pushrods that will cause problems. In your case however, I think your fuel should be ok. Give it the sniff test to be sure..
Just Carbs
Well-Known Member
I haven't had any problems with 6-month-old e-gas.
I haven't let any sit more than a year, but it to was still good, no smell.
All low compression car motors.
Now, three years in the weed eater, it don't run.
I haven't let any sit more than a year, but it to was still good, no smell.
All low compression car motors.
Now, three years in the weed eater, it don't run.
3175375
Senior Member
I am ignorant of the deterioration of fuel, but will share my experience.
I have over 10 vehicles. A couple rarely get started, less driven.
I keep most of them in a heated shop.
I recently got Elwood, my 68 Plymouth Fury II 4 door sedan out and about.
I did rebuild the 2 barrel carb 5+ years ago and recently dumped about 5 gallons of 10% ethanol fuel into the tank after replacing the sending unit.
The car is running great.
I also have a 67 Corvair convertible that has sat for 5+ years and I haven’t done anything with it. However, I bet it would start.
I also have a 66 Corvair convertible that I have tried to start, but it won’t.
I believe that I got it to partially fire with ether, but I need to revisit that car.
I also remember driving home a 57 New Yorker (it was my postman’s car and had sat under a giant pine tree for years) that I got for free after I put a battery in it and sprayed some ether down the carb and dumped some fresh fuel in the tank. This was circa 1983 in Southern Kalifornia.
I did something similar with a 67 T-Bird in 1997.
I guess what I am sharing is that your mileage may vary.
Thanks for bringing this up, though as I may siphon the 66 Corvair’s gas tank out and put fresh fuel in it with some fuel stabilizer or seafoam before I play with it again.
I have over 10 vehicles. A couple rarely get started, less driven.
I keep most of them in a heated shop.
I recently got Elwood, my 68 Plymouth Fury II 4 door sedan out and about.
I did rebuild the 2 barrel carb 5+ years ago and recently dumped about 5 gallons of 10% ethanol fuel into the tank after replacing the sending unit.
The car is running great.
I also have a 67 Corvair convertible that has sat for 5+ years and I haven’t done anything with it. However, I bet it would start.
I also have a 66 Corvair convertible that I have tried to start, but it won’t.
I believe that I got it to partially fire with ether, but I need to revisit that car.
I also remember driving home a 57 New Yorker (it was my postman’s car and had sat under a giant pine tree for years) that I got for free after I put a battery in it and sprayed some ether down the carb and dumped some fresh fuel in the tank. This was circa 1983 in Southern Kalifornia.
I did something similar with a 67 T-Bird in 1997.
I guess what I am sharing is that your mileage may vary.
Thanks for bringing this up, though as I may siphon the 66 Corvair’s gas tank out and put fresh fuel in it with some fuel stabilizer or seafoam before I play with it again.
In the world of emergency generators, I discovered some "fuel regeneration" additives which could be purchased to put in the gasoline tanks of these critical-infrastructure machines. Was supposed to keep the fuel "fresh" for up to a year or so, they claimed. I even found a camping place about an hour away that was supposed to sell it. No mention of "ethanol" in respect to the gas in the tank, just "gasoline", as I recall.
When I found this stuff, the use of home/residential emergency generators was starting to rise. Most of these units were fueled by gasoline, as most now are run by natural gas.
These emergency generators were usually owned by a public utility or sub-division utility in case the main electricity service stopped for one reason or another. As such, I suspect they had quarterly or longer maintenance and operational checks/run-time, so the fuel could be reasonably fresh in them? The fuel use extender additives, with freshened fuel, them kicking-on automatically was supposed to happen flawlessly and reliably.
I never did discover the main ingredient in these additives of what made them better than the normal "storage" additives. Might have been something simple that would work with the compression ratio of the generator engines?
Never did hear about anybody trying the additives in their vehicles, though.
Take care,
CBODY67
When I found this stuff, the use of home/residential emergency generators was starting to rise. Most of these units were fueled by gasoline, as most now are run by natural gas.
These emergency generators were usually owned by a public utility or sub-division utility in case the main electricity service stopped for one reason or another. As such, I suspect they had quarterly or longer maintenance and operational checks/run-time, so the fuel could be reasonably fresh in them? The fuel use extender additives, with freshened fuel, them kicking-on automatically was supposed to happen flawlessly and reliably.
I never did discover the main ingredient in these additives of what made them better than the normal "storage" additives. Might have been something simple that would work with the compression ratio of the generator engines?
Never did hear about anybody trying the additives in their vehicles, though.
Take care,
CBODY67
Sixpactogo
Well-Known Member
I'm pretty sure you got some bad advice from Mike. Drive the car and if it runs good, you haven't hurt it any. If it stumbles upon acceleration, you may have to look into it some but premium gas won't be Varnish in 7 months. My cars sit from November until May normally but I add some Sta-bil to the gas when I shut them down for the winter. They run just fine year after year. I just try to make sure I get the Premium fuel without ethanol. If you get a stumble, you more than likey at some point put ethanol laced gas in and that has a tendency to eat the accelerator pump.
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Just Carbs
Well-Known Member
Right.
If gas went sour in six months, none of these occasional use cars would be on the roads.
volksworld
Well-Known Member
owning a repair shop in NY for over 40 years I can say that the only consistent trend was lack of consistency...I've seen cars parked for 2 or three years where everything turned to brown goo and destroyed carbs, injectors , pumps and sending units...and i've seen others go over 10 years and be fine...I wish I could have figured out which brands of gas did this and why...but who remembers the last place you filled up before you parked it...I also knew dirt bag gas stations that dumped their waste oil and other cleaning solvents into the gas to get rid of it ...and knew another guy that bought tankers of gas and held it for extended periods of time till the price went up and made millions so not all gas is created equal
Nadir Point
Member
My new Yorker's had the same tank of gas in it for at least five years. I topped it up once a couple years ago, IIRC. I'm pretty severely disabled, so I haven't done much with it lately, except to take it down off the lift every so often when I need to use that for something else. Hasn't failed to start right up and run fine yet, but I'm starting to think it might need a timing chain. 2-stroke in the fuel. Pint per tank's probably plenty. I use a quart. YMMV.
Here's an important issue that many might not be aware of. We are looking at all "gas" in the USA to be "the same", which it is not. Sure, it goes intot the tank and the car runs well, but the chemistry which makes that happen varies between EPA Ozone Non-Attainment areas of the nation. According to the last Exxon/Mobil map of which areas needed to have which blend of fuel, there were about 15 different blends of fuels. Each with their own tweaks to make them "legal" to sell in particular areas.
There are broad expanses of the USA where "normal", un-doctored fuel can be sold, away from metro areas. BUT that does not mean the fuels sold out there are not E10! To further complicate things, the pump labelling state legislation so the consumer knows what they are buying (ethanol concentrations) are NOT consistent, so an un-labeled pump can be dispensing ethanol'd fuels.
Just as there is www.gasbuddy.com to see where the lowest gas prices are in your area, there also is a website to discover many things about gasoline. Seems like it is www.fuel-kits.com ? Includes a list of fuel additives which also contain alcohol too. Many are near larger lakes where fuels need to be without ethanol as ethanol absorbs moisture. One of the first places that ethanol in fuel was "discovered" was in boats which had fiberglass fuel tanks.
To my knowledge, if E10 is sold in 87 Pump Octane fuel, then E10 would also be sold in Premium 91-94 Pump Octane fuels, as a general rule. This might be a regional/state "thing" that certain brands would have 87 Pump Octane be E10 and 93 Pump Octane be E0, but I somewhat doubt that. Several years ago, there were some private-brand fuels which were exclusively E0, from the least expensive octane level to the top octane level. I'm not sure if they are still that way or not. Plus, the states these stations were in had NO ethanol labeling standards!
End result, "gas" is not nearly as universal as it used to be, when the air was cleaner and sex was dirtier, so to speak. It might all work the same modern EFI cars, and even in our older carb'd cars, but some better than others.
How fuel is blended now is different from 50 years ago. Back then, if it was one of the main brands, it was BLENDED to be what it was in THEIR refineries, then delivered to a local agent, stored in those tanks, and then delivered to the local stations in a truck with the fuel logos on it. Now, the distribution model is more like the refineries blend a "universal" unleaded fuel, pipe it to distribution terminals. When the tank truck pulls up to the terminal, the terminal operator then punches buttons to get the correct BRAND's "additive package" and octane level added to that fuel to make it a "name brand fuel" for the particular brand. "Splash blended" rather than "full-refinery blended" fuels. The local agents have vanished, too.
Perhaps this might help explain why such varied experiences with "aged fuel" can result?
Enjoy!
CBODY67
There are broad expanses of the USA where "normal", un-doctored fuel can be sold, away from metro areas. BUT that does not mean the fuels sold out there are not E10! To further complicate things, the pump labelling state legislation so the consumer knows what they are buying (ethanol concentrations) are NOT consistent, so an un-labeled pump can be dispensing ethanol'd fuels.
Just as there is www.gasbuddy.com to see where the lowest gas prices are in your area, there also is a website to discover many things about gasoline. Seems like it is www.fuel-kits.com ? Includes a list of fuel additives which also contain alcohol too. Many are near larger lakes where fuels need to be without ethanol as ethanol absorbs moisture. One of the first places that ethanol in fuel was "discovered" was in boats which had fiberglass fuel tanks.
To my knowledge, if E10 is sold in 87 Pump Octane fuel, then E10 would also be sold in Premium 91-94 Pump Octane fuels, as a general rule. This might be a regional/state "thing" that certain brands would have 87 Pump Octane be E10 and 93 Pump Octane be E0, but I somewhat doubt that. Several years ago, there were some private-brand fuels which were exclusively E0, from the least expensive octane level to the top octane level. I'm not sure if they are still that way or not. Plus, the states these stations were in had NO ethanol labeling standards!
End result, "gas" is not nearly as universal as it used to be, when the air was cleaner and sex was dirtier, so to speak. It might all work the same modern EFI cars, and even in our older carb'd cars, but some better than others.
How fuel is blended now is different from 50 years ago. Back then, if it was one of the main brands, it was BLENDED to be what it was in THEIR refineries, then delivered to a local agent, stored in those tanks, and then delivered to the local stations in a truck with the fuel logos on it. Now, the distribution model is more like the refineries blend a "universal" unleaded fuel, pipe it to distribution terminals. When the tank truck pulls up to the terminal, the terminal operator then punches buttons to get the correct BRAND's "additive package" and octane level added to that fuel to make it a "name brand fuel" for the particular brand. "Splash blended" rather than "full-refinery blended" fuels. The local agents have vanished, too.
Perhaps this might help explain why such varied experiences with "aged fuel" can result?
Enjoy!
CBODY67
SuperDave
Member
My car, Project Turd, only received 91 octane non-ethanol gas, dosed with Stabil additive (1 oz per 5 gallons) AND synthetic marine two-stroke oil (1 oz per 8 gallons). It sees a couple hundred road miles a year. I fire it up once a month for 10 minutes in winter. I live near a large lake so the gas I buy supposedly is decent. I also park it with a battery tender attached (I made my own, 13 volts at 0.5 amps, get em at Amazon, keeps the battery fully charged but not enough current to overcook it & boil out the acid).
Gas can go bad inside of 6 month in the wrong conditions. If I were you, IF IT RUNS, I'd drain as much as I could from the tank, add fresh non-ethanol gas (at least 5 gallons) dosed with stabilizer & 2-stroke oil, AND double dose it with a can of STP carb cleaner or B12 cleaner and DRIVE IT. Not just idle, low speed operation won't get the fuel thru the main jets. Get it on the highway and stand on the loud pedal a few times. Go clock 50-100 miles on it. That'll clean and flush out the entire fuel system & carb completely. Then I'd change out the oil & filter before parking it on a battery tender.
My car is a weekend warrior hot rod (4bbl, cam, headers) that sees Cars n Coffee & car shows, not much else. Starts up every time. Inside of the carb is clean as a whistle. Runs like a raped ape. When my daily driver overheated and warped the head, it was my only running car for 2 weeks. Burned thru a hundred gallons. It only gets 8 mpg IF I can keep my foot out of it. Which ain't easy, considering how nice she sings when it's stood on.
Good luck. Worst case scenario, you may need a carb rebuild or even a new one.
Gas can go bad inside of 6 month in the wrong conditions. If I were you, IF IT RUNS, I'd drain as much as I could from the tank, add fresh non-ethanol gas (at least 5 gallons) dosed with stabilizer & 2-stroke oil, AND double dose it with a can of STP carb cleaner or B12 cleaner and DRIVE IT. Not just idle, low speed operation won't get the fuel thru the main jets. Get it on the highway and stand on the loud pedal a few times. Go clock 50-100 miles on it. That'll clean and flush out the entire fuel system & carb completely. Then I'd change out the oil & filter before parking it on a battery tender.
My car is a weekend warrior hot rod (4bbl, cam, headers) that sees Cars n Coffee & car shows, not much else. Starts up every time. Inside of the carb is clean as a whistle. Runs like a raped ape. When my daily driver overheated and warped the head, it was my only running car for 2 weeks. Burned thru a hundred gallons. It only gets 8 mpg IF I can keep my foot out of it. Which ain't easy, considering how nice she sings when it's stood on.
Good luck. Worst case scenario, you may need a carb rebuild or even a new one.
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