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Can fuel go bad????????? :/

  • Thread starter Thread starter DirtyD916
  • Start date Start date Oct 12, 2005

DirtyD916

Active Member
May 25, 2003
804
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Norcal 916
Oct 12, 2005
#1
  • Oct 12, 2005
  • #1
well my car hasnt been started for like 6 months and i was curious if the fuel goes bad. I have about 9 gallons that have been sittig in the tank and before i crank it over i want to be sure that no "sludge" gets sucked up into the injectors. My friend said that i will have to drop the tank and replace it with a new one, but before i do all of that i wanted your opinion. I am selling the car so i dont really care if it doesnt run top notch.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Oct 12, 2005
#2
  • Oct 12, 2005
  • #2
DId you put any fuel treatment in the tank to help keep it from varnishing?

There is no way to know, but you should be alright. The same fuel has been varnishing in the fuel rail and injectors, etc anyhow........

Good luck.
 
D

Daggar

New Member
Jul 19, 2004
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Oct 12, 2005
#3
  • Oct 12, 2005
  • #3
Yes... fuel goes bad. It turns into a varnish over time. You would probably do well to drop the tank and drain it if it's had no fuel stabilizer in it. The fuel going up the injectors and sitting in the fuel lines it probably no good either. Once the tank is dropped, disconnect the rails and blow the line out forcing the old fuel towards the tank. Might be a good idea to clean the injectors as well. Check parts stores/machine shops in your area to see if any of them has an injector cleaner/test stand.
 
D

Daggar

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Oct 12, 2005
#4
  • Oct 12, 2005
  • #4
Hiss beat me to it. LOL
 

DirtyD916

Active Member
May 25, 2003
804
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38
Norcal 916
Oct 12, 2005
#5
  • Oct 12, 2005
  • #5
would i be able to just dump the gas out of the tank and then refill it or do i need a new tank?
 
D

Daggar

New Member
Jul 19, 2004
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Oct 12, 2005
#6
  • Oct 12, 2005
  • #6
No need for a new tank so long as it not all rusted inside.
 

Mavrick

Founding Member
Aug 29, 2002
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46
Collingwood, ON
Oct 12, 2005
#7
  • Oct 12, 2005
  • #7
Are you guys serious? Do you really think that old gas is worth going through all this trouble? Gas had sat in my car for nearly a year and it still seemed to burn through without any problems..

Personally i wouldn't worry about it, but i've never seen the ill effects from it.
 

vristang

15 Year Member
Mar 31, 2005
4,933
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124
Seattle
Oct 12, 2005
#8
  • Oct 12, 2005
  • #8
Daggar and Hissin are right, the safest thing to do is to drop the tank and KNOW that everything is right.

However, you would probably be fine with adding a water remover and topping the tank off with fresh fuel. Then again, it would suck to have just topped off the tank, and then find out that all the fuel is bad and have to pull a topped off tank.

The choice is yours, but I have a ton of respect for the opinions of both Hissin and Daggar.

jason
 

Maryland Stang

Active Member
Aug 21, 2002
1,656
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39
Greenville, NC
Oct 13, 2005
#9
  • Oct 13, 2005
  • #9
I have to deal with a lot of bad gas (I'm a small engine mechanic too) and unless the gas actually smells bad I wouldn't worry about it. The varnish everyone speaks of is what is leftover after the fuel evaporates. I find it highly unlikely the fuel has evaporated to the point of varnish after only 6 months.
 

crazypete

All my crevices are greased.
Oct 22, 2004
930
4
18
Arlington, MA
Oct 13, 2005
#10
  • Oct 13, 2005
  • #10
Ditto on the too much trouble. My car has sat more than it has moved over the past 3 years and no such trouble.

Just add 3-4 containers of fuel system cleaner and let the system clean itself.
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
1,796
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0
Woodward Ave.
Oct 13, 2005
#11
  • Oct 13, 2005
  • #11
The '87 GT that I bought off a guy sat with gas in the tank for 4 years. The car started right up once the battery was charged..

Just start the car, drive the bad gas out of the tank and then fill up with cleaner / new gas.
 

Euphoric306

New Member
Apr 5, 2004
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Oct 13, 2005
#12
  • Oct 13, 2005
  • #12
and run some fuel injector cleaner as stated above after the bad gas is gone
 
B

BaXTeR3221

Member
Jan 12, 2004
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Orange County, NY
Oct 13, 2005
#13
  • Oct 13, 2005
  • #13
ditto again. I let gas sit in my stang from october-ish to around april, maybe started it twice and it was fine. Id throw in some stabilizer just to be safe, but i personally think dropping the tank is more trouble than its worth.
 
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