Diesel fuel, how old is too old?

[newbury]

I sometimes leave my Kubota B26 with the same tank of gas for 2 years or so.

You need to think either "fuel" or "diesel". Or you are going to tell someone to "gas 'er up", they will, and your rig won't run.

 

[California]

Seems to me the only issue with years-old diesel is be sure to filter out water and crud (stringy bacteria slime) before it goes through the fuel system. If what reaches your fuel pump is clean then it should run fine.

When I bought my first Yanmar in 2003 there was an abandoned farm fuel tank next to it. The fuel in the seldom-used Yanmar burned my eyes so bad that I'm sure it was old spec hi-sulphur pre1993 diesel from that farm tank. Perhaps the farm tank was last filled many years prior to 1993. The tractor wasn't easy to start until I refueled with fresh diesel, but that old stuff didn't clog the filter and didn't seem to hurt anything (except my eyes!).

 

[SPYDERLK]

If stored outside you always gotta worry about water over time, but I wouldnt worry about the fuel itself for 20 years. And even then not much. Water beyond what the additive can handle will be on the bottom. That slug of H2O accumulated after long non use will cause an issue with your filter. If this happens youll probably need to replace it and fill the filter housing with additive then run it awhile to clear all water. Once should be enuf except severe situations where a lot of water accumulates over [usually] long period. Then, draining the tank to remove the water may be necessary to avoid repetitive filter changes.
larry

 

[SPYDERLK]

You need to think either "fuel" or "diesel". Or you are going to tell someone to "gas 'er up", they will, and your rig won't run.

Exactly:thumbsup:

 

[Gary Fowler]

Strategic Petroleum Reserve (United States) - Wikipedia, the free encyclopedia

I know that every military base has strategic reserves of refined fuel stored for months of operations that is totally different from the strategic petroleum reserve just in case supply is interrupted like for instance terrorist attacks on refineries. If a few of the larger refineries were destroyed, it wouldn't make any difference how many barrels of crude was on hand. Just like the K and C rations, this stuff may be on hand since WWII but still works perfectly. The old high sulfur fuel didn't have a problem with bacteria contamination like the low sulfur stuff does as the sulfur didn't allow for bacterial growth even if water was present.

 

[Gale Hawkins]

Some years ago (10+) they were installing new sewer lines in my area. The contractor hit a buried fuel tank along side a party store (in alley). The store used to have fuel pumps back in the 50's-70's as a Greyhound Bus Stop. Anyhow the local contractor pumped out the several 100's gals of fuel and used it in his equipment in exchange for not charging the property owner to remove said tank. I know the owner of the store for the last 30 yrs and he did not know there was a diesel tank buried there as the pumps were gone when he bought the store in early 1980's.

That was an interesting case and shows the half life of the old diesel fuel must be a long long time. Diesel was not worth pumping out I guess at the time.

 

[lostcreekranch]

My fuel tank holds about a years worth of fuel now that my major projects are done and I have never had an issue with water, rust or algae. The tank is inside a closed building so no rain can get to it and the tank caps seem to be pretty air tight. I have been working in the shop at nights and scared the beejesus out of me when the tank walls suck in from the slight vacuum, sounds like someone hit the tank with a hammer. I do have a 10 micron filter on it that all the fuel goes thru before it hits any of my equipment. I changed out the filter after about 3 years when the fuel flow got weak but it turned out that it was just the battery going bad and the new filter was the same way so I don't think my filter was plugged up at all after pumping only about 400 gallons.
If you can believe those reality shows, the Gold Digger in Alaska supposedly got a dozer running after setting 10 years with the same fuel. I don't think he even changed the oil, not that I would try something like that. I do know that the USA has millions of gallons of emergency reserve fuel setting in underground salt dome storage that may be 50 years old. They released some of it for domestic use during the Gulf War because of the oil shortage.

Gary;

Your fuel tank needs a vent. Made one for mine from some 1 1/2" PVC. Have some screen and very fine mesh glued into a coupling to keep trash out.

Rick

 

[bandaidmd]

In the areas with a lot of boats there are fuel polishing services. Boats have large tanks and mostly little use so fuel sits for a long time. These companys have a large portable filter and pump set up (racor is one brand) and recycle your fuel to keep it fresh. pump out thru filters to a storage tank then filter back into your tank.

 

[Midniteoyl]

I know that every military base has strategic reserves of refined fuel stored for months of operations that is totally different from the strategic petroleum reserve just in case supply is interrupted like for instance terrorist attacks on refineries. If a few of the larger refineries were destroyed, it wouldn't make any difference how many barrels of crude was on hand. Just like the K and C rations, this stuff may be on hand since WWII but still works perfectly. The old high sulfur fuel didn't have a problem with bacteria contamination like the low sulfur stuff does as the sulfur didn't allow for bacterial growth even if water was present.

The fuel is continually refreshed by being used and replaced. But ya, it doesn't go 'bad' per say..

 

[Mace Canute]

Just one of several sites that talk about biological contamination of diesel fuel.

Diesel Bug Explained - Bacteria Contamination of Diesel