Old fuel?

Brian VT

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The truck I got has 2 fuel tanks. The one it was set on when I got says it's almost empty. The other one says it's full.
I have no idea how old the fuel in the full tank is. Should I just run it and hope for the best, or put some treatment in it, or drain it?
 

franklin2

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I have never had a problem with old diesel fuel. I have had lots of problems with old Bio-fuel. I would run it, and then after you have gone through a tank on both tanks, just change the fuel filter.
 

u2slow

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With old diesel fuel, I typically run it in my truck that's got the extra primary filter, and cut it with new fuel and dose with additive. Haven't had any that appeared grossly off/contaminated yet.
 

ih8minimumwage

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Dump some Dieselkleen or ATF in both tanks, run it like that 1/4 to 1/2 down and top off with clean fuel. Pick up an extra fuel filter and water separator element for when you think you've got all the old fuel out.
 

Cubey

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My RV had questionable fuel in it when i got it. It had weak idle when in gear and would stall when coming to a stop sometimes. Once I put fresh fuel (with Howes antigel) and drove it on the highway 300 miles it was fine.
 

gandalf

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The two possibilities for contamination are water and algae. The water will show in the water seperator, and can be dealt with. If you're at all concerned about algae I'd suggest that you add a dose of algaeside, try to kill that algae. If you do that have a couple spare fuel filters on hand. Dead algae will tend to plug the fuel filter.
 

Big Bart

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Diesel seems to be able to sit for years and still work good. So I would not be afraid to use 3 year old diesel. Now algae is a whole other thing.

I have had two diesel boats. Both at some point had algae blooms even using bio bore. (Boat was inland in temps over 100 degrees. Diesel foaming out the vent lines down the side of the boat.) I think it was from the fuel dock diesel, but water in boat fuel tanks happens. (Comes in likely because the fuel tank cap which points up. So splashing water, rain, and washing the boat all can let water seep in. Vent lines on side of boat take in water from spray and condensation from being in humid places year round.)

If you do have algae pump out the fuel, it clogs your filters and likely makes a more inviting home later. First time it happened I filtered it via a transfer tank. (Now use for pumping old fuel out of my Gator, snowmobiles, and other equipment. We don’t have any non-ethanol pump options here in CA so gas goes stale after 6-8 months.) Even after filtering the fuel and putting it back in I still had heavy algae on primary and secondary filters. (Some diesel stays in the tank and the algae lines the tank, fuel lines, and IP. Second time it happened I pumped it out and took it to hazardous waste 5 gallons at a time. Put in fresh fuel and a double dose of bio bore.

At a minimum I suggest suck out the fuel and filter it. But suggest you just dispose of it.

I used this generic Chinese made transfer tank the first time due to its low cost. I added a two filter system to it. Changed the filters after pumping it out. So pumping back in it would go through two new filters. Remember filters work in one direction. Had I not swapped the filters around at a minimum (I replaced them.) when the diesel went backwards to fill the tank, it would have flushed the algae out of the filter back into the tank.

I used one of these generic China ones, added a two filter diesel set up to filter and do water separation.

 

drewr13NJ

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My IDI is an old farm truck. The front tank had a pin hole in the sending unit pickup where it rusted through up on top of the tank, hence the truck would run crappy on the front tank. Well, I switched it from the rear tank and had a mess all over by driveway because of the pin hole, but even though that old red diesel smelled stale, the truck ran! My FSV got stuck on the front tank, so I ended up removing it and installing a large rear tank from CDD. I took that old red fuel to work and put it in the bulk tank and the locomotive. We haven't had any problems that I know of from it, so I wouldn't be too worried about it.

My mom's house has an old buried diesel/fuel oil tank in the back yard, which as been sitting for who knows how long. I have contemplated trying to pull some out of the tank and put in my truck to see what happens.
 

franklin2

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My IDI is an old farm truck. The front tank had a pin hole in the sending unit pickup where it rusted through up on top of the tank, hence the truck would run crappy on the front tank. Well, I switched it from the rear tank and had a mess all over by driveway because of the pin hole, but even though that old red diesel smelled stale, the truck ran! My FSV got stuck on the front tank, so I ended up removing it and installing a large rear tank from CDD. I took that old red fuel to work and put it in the bulk tank and the locomotive. We haven't had any problems that I know of from it, so I wouldn't be too worried about it.

My mom's house has an old buried diesel/fuel oil tank in the back yard, which as been sitting for who knows how long. I have contemplated trying to pull some out of the tank and put in my truck to see what happens.
Just don't get caught with the red fuel driving on the road. Even if it's a farm use truck they may still try to get you on a public road. They seem to be that way now about everything.
 

Brian VT

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I don't even know how to check for algae.
The fuel gauge is whacked so I thought I'd try to probe the depths of the tanks but the filler tubes go horizontal so no go there. I have no idea how I could check for algae.
When I changed the fuel filter the fuel did have a slight greenish tint to it but I didn't see any "crap" in it.
 

Old Goat

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The Govt. will really stick it to you for using tax free Red Diesel, yet look at all the Diesel vehicles running around all over the country burning French Fry oil, used Engine oil, used Atf and what ever crap they can throw in their tanks and pay no road tax. And the Govt. does nothing about that,
let alone the Electric vehicles that go free also.

I have read of the big fines they throw at people.

This is one reason the Govt. want us to pay by the mile, it`s coming folks.

Goat
 

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