Hello everyone, it's been a long while since I have posted here. I have a number of serious surgeries and been laid up better part or the last 18 months. Anyway all things considered I'm in much shape and getting stronger slowly but in the right direction. My39'Chevy (350/700r4) has not run in quote awhile. If fact there is about 2-3gallons of gas in that tank that is very old. I couldn't resist pulling it out of its hibernation and running it a few miles. Since it kicked right off, and I mean instantly I thought that old gas would be Ok to get down to the station. But the car stumbled and ran rough, wouldn't accelerate very well so I pulled it back in the garage to get some advice. I don't know if its ok to mix old gas with new. I heard both ways, don't contaminate a tankful of new and re oxygenate the old gas with some hi octane. I figure this is the best place to get some advice. If fact there have been a few instances where I would have better off to listen to some. I know the best way to handle this is pull that tank, but I'm not that strong yet. What's the next best thing to do?
Do you think if I just try to siphon out as much as I can, if I run the lines dry then refill with fresh that would work? Then I wouldn't have to reassemble anything except the Frammfuel filter.
Put in premium next fillup. Modern gas has lots of detergents etc which help clean fuel injectors & cars which sit. You should be able to open a fuel line and let it drain out without too much exertion? (depends on ride height, access, etc. ) Posted from the TJJ App for iPhone & iPad
I'd fill it up and run it out, it won't hurt a damned thing, it'll run better on the second tank. Let her rip.
That sounds like what I wanted to hear, if it started that fast and ran without dying out it should be OK once all the stale stuff is gone. I was told it half made sense the bad gas would contaminate the new gas and prolong the situation, but the way that thing guzzles gas it should be gone quick.
Add a half can of Seafoam gasoline additive fill it up and let it rip. The additive WILL clean up the fuel.
Yes on that Sea Foam. Dump in a can and add 10 gallons, let it idle in the driveway and rev it every now and then.
I pulled an 80's truck out that had been sitting in a barn for 10yrs. Topped off the tank with 5gal of fresh gas (all I could fit in with the old stuff), replaced the battery and tires and made a 2hr drive to my house with zero trouble. IMO, fill it up wit fresh and drive the old stuff out.
@slammed,sounds like a plan,gotta,work and the additive can't hurt anything but my wallet. But that's not major damage.
Top it up with premium and go for a long drive it will smarten up on its own. I have used this method many times and it always works.
Fred is right---aound Dallas I hear it's 30-60 days and gas is on the way to going bad. I never fill the 40's tank---
I was just having a conversation with a guy I was buying a line trimmer from. He claims modern gas with ethanol breaks down in as little as 30 days. For two cycle mixes he recommends disposing of the old gas and mixing new. For a v8 engine he said that if the tank is less than half full, add fresh gas to full and add some Sea Foam to dry the gas out. Run the hell out of it to almost empty, refill and good to go.
Several stations around here are selling premium advertised as "no alcohol".. I'd fill the tank with a similar fuel, coupla cans of Seafoam in the next few tanksful.. Ya might be postponing the inevitable carb teardown, but it may just clean up by running ..who knows..
Add some Tectron, it does wonders. I ran an old SBC truck that sat for many many years. Filled the carb bowl time after time to get it cleaned upo and take fuel from the pump and dumped a gas can full of techtron and gas in it. Let it idle for almost 45 minutes. Worked great........
FYI, I can't remember the name but there is a new fuel additive similar to sta-bil that is formulated for alcohol/ethanol blended fuels and prolongs the life for a great while. It is carried in boat stores. Was made so the fuel would be safer for carbs, rubber lines etc.
If you can drain or siphon the old gas out without much trouble you will be ahead of the game to get as much of it out as you can before dumping new gas in. On some setups it's just flat too hard to do that and then I'd dilute the old gas with new and go. From experience it depends on what the old gas smells like too. If it smells like paint varnish flush the tank and if it just smells like gas you should be ok. I just fired up my box with wheels that has been sitting for almost two years and did pretty much like the guys said to do and put putted to town and filled it with premium and drove that tank down pretty low and filled it with premium again. Five tanks later it is running great. That's a little 1600 CC 16valve fi engine that is a lot pickier about good gas than a lot of older engines.
If you dilute it, it will just stay in your system. (It has been covered a lot here that ethanol in gas chews up rubber, therefore you need to start using fuel injection line instead as a side note). Long story short your engine will still run like crap, but less than before. It is best to drain it and start over. Gas now goes bad usually within 1 month to maybe 3 if you are lucky; If you park it for a long period of time again you can use fuel stabilizer and that will take care of you so you don't have to worry about this. To fix your problem now, drain the gas and be on your way. Don't use additive... it's a waste of money and there is no guarantee that this is going to fix your problem
I think these all reasonable. A TV personality who has a type of street rod, custom, restoration program bought my buddies 40 Ford. First thing he did was clean that gas tank and carburetor. He said it ran like a different car providing additional power. I was as familiar with that ride as I am with mine. That car ran great to begin with. No way he could beat me but a good running car. Too big a job for me right now, I just can't believe it makes that BIG a difference.
I would check for rust in the tank.If you put fresh gas in a rusty tank it will just distribute that rust through every thing. ask me how I know this
The Jalopy Journal
