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Fuel After Storage

  • Thread starter Thread starter nightrider50
  • Start date Start date Mar 22, 2010
N

nightrider50

Member
Aug 28, 2003
186
0
17
California
Mar 22, 2010
#1
  • Mar 22, 2010
  • #1
Crank broke in half, car sat for a month, put stabilizer in the tank, sat for another year+. Getting close to done with the new build. Wondering what I should do, if anything, about the fuel. There was at least 1/2 tank full when the crank snapped. Didn't get a chance to run it with the stabilizer.
 

ID89GT

10 Year Member
May 26, 2008
1,659
18
49
Spokane Valley, WA
Mar 22, 2010
#2
  • Mar 22, 2010
  • #2
I would drop the tank and clean it out really good. If its been sittin that long then you risk running bad gas through the lines and such and could cause some other problems that could be avoided.
 

Maryland Stang

Active Member
Aug 21, 2002
1,656
30
39
Greenville, NC
Mar 22, 2010
#3
  • Mar 22, 2010
  • #3
There may be a problem with the fuel but if it was stabilized it really should be okay. I deal with a lot of gas that sits for significant amounts of time (I have some equipment that is rarely used but I still have to have it). It also has a lot to do with whether it was summer or winter blended fuel. I've seen summer blended fuel go bad even with stabilizer in it in a matter of 5 to 6 months. Winter blended fuel tends to stay good for a whole lot longer with stabilizer. I have one emergency generator that has had the same fuel in it for over 3 years now and the generator still starts up and runs when it's tested. We will change that fuel out shortly just because of how long it's been in the tank.

A lot of times you can just smell the fuel. Pull the cap off and give it a whiff. If you smell varnish then the fuel has gone bad. If it smells like gas then it's probably still good.

You can also prime the fuel system a time or two and pull some fuel out of the shrader valve and see what it looks and smells like. Like I said above, it should smell like gas and it should have a very light to clear color to it. If it's an amber color then get rid of it.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,368
18,115
224
Massachusetts
Mar 22, 2010
#4
  • Mar 22, 2010
  • #4
I let my car sit 6 years with no stabil and half a tank of gas. I siphoned the tank down as far as I could and put 10 gals of fresh gas in and it started right up. That was a year ago.

The gas i took out...well, it ended up in various vehicles I had about 1/2 gallon at a time until it was gone.
 
N

nightrider50

Member
Aug 28, 2003
186
0
17
California
Mar 29, 2010
#5
  • Mar 29, 2010
  • #5
Alright so from what I've gathered:

1) Take the cap off and take a big wiff, if it smells ok then...

2) Run fuel through the line to the schraeder valve (not the rails/injectors) to fill up a cup and check the color/smell. If it looks/smells like new gas, party on. If it doesn't smell like good gas or look like good gas then...

3) Siphon as much out as possible and put fresh gas in. Drop the tank and clean it out if the gas is really foul.

Sound like a good process? What about the minimal amount of fuel that sat in the rails/injectors for that time too; anything I should look into with that?
 

Maryland Stang

Active Member
Aug 21, 2002
1,656
30
39
Greenville, NC
Mar 30, 2010
#6
  • Mar 30, 2010
  • #6
nightrider50 said:
Sound like a good process? What about the minimal amount of fuel that sat in the rails/injectors for that time too; anything I should look into with that?
Click to expand...

Yes.

I would only worry about the rails and injectors if the gas is really, really fouled. The gas in the rails and injectors has no way to get in contact with the air so it would probably take longer to go foul anyway. Since you put fuel stabilizer in the gas before you put the car away the fuel in the lines could stay fresh for any number of years.

What happens to gas is this...

When left exposed to the air, vented tank or a non EPA gas tank the fuel can start to seperate into it's base components. As it does that the lightest of the components starts to evaporate. That's when you start to get that varnish smell. As the heavier components start to evaporate you get the heaviest components being left behind. That would be that sticky, dark brown-black crap you find in a carb that someone let the fuel evaporate out of.

Basically what the stabilzer does is help prevent the components from seperating. If they don't seperate then they can't evaporate as quickly. Now since your fuel is in the lines and injectors it has no way to get in contact with the air to start the seperation process. Add in the fuel stabilizer and you can see where the fuel shouldn't be a problem.
 
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