How long does stored diesel last?

[Canibul]

The owner of the marina where we're presently living brought his boat down here 30 something years ago. The boat is being scrapped now, destroyed by termites, but before they removed the engines he fired them up to show the buyer that they were good. I asked him how old the fuel was, and he said it was still the same fuel he came down to the islands with. It's at least 30 years old, and there were no issues with it at all.

[HappyMdRSailor]

Originally Posted by Canibul

The owner of the marina where we're presently living brought his boat down here 30 something years ago. The boat is being scrapped now, destroyed by termites, but before they removed the engines he fired them up to show the buyer that they were good. I asked him how old the fuel was, and he said it was still the same fuel he came down to the islands with. It's at least 30 years old, and there were no issues with it at all.

like 30 yo wine... Perfecto!

Was the Titanic coal or diesel fired???

[CSY Man]

. Was the Titanic coal or diesel fired???

Coal.
You can buy coal from the Titanic on eBay..

[newhaul]

Originally Posted by a64pilot

I think it's actually an algae, not a Bacteria, but I really don't know?

The bugs are an algae and they seem to collect on the bottom and sides of a tank.
Also I have run 30 plus year old fuel thru my trucks with no problems I actually saw an increase in performance when running the old fuel.

[SWFLman]

I'm restoring a boat that has been on the hard for at least the last 15 years. Pulled the diesel tank inspection plate the other day and discovered the tank was completely full. I'm pumping it out in drums in a couple of weeks to inspect the tank...... but not sure what I'm going to with in all.......

[ontherocks83]

I would run it. If it went in clean and is in a sealed container then I wouldn't worry. I know old diesel is good forever. I do not know what is in new diesel that could make it go bad. If it was in a vented container I would polish it first incase there is moisture

[moseriw]

I can only speak for (bloody) european standards. In Europe they started around 2003 to add biomasses to the diesel.

I have no problem with my diesel car as I burn the diesel within a few months and I have added gear to my car to be able to use rape or sunflower oil which is a problem to keep in store. Once it get's below 0° C without additives (Diesel) it coagulates.

The problem with the bloody new green diesel is that the biomasses contain germs and ruin diesel that is stored more than one year will get the diesel's black death. Tests of diesel additives did not really satisfy me.

On problem with germs is oxigen. If you keep the tank full and UN-vented you will have a good chance to avoid the pest. (Same with freshwater tanks!) AND even an empty tank has enough diesel in it to get infected.

[ontherocks83]

Is there a good (read easy) way to test diesel? i.e. through a chemistry kit ( kind of like the ones you buy at home depot to test water for lead or kitchens for meth) Now my interest is up and I would totally put a vented tank outside with diesel and a sealed one and test every 6 months for a few years to see the results.

[hamburking]

The diesel fuel itself will last for many years. The trouble is contaminants...like a "bloom" or rust chips, or sediment. Filtering is prudent.

I recall the book NORTH TO THE NIGHT they find a barrel of diesel in an abandoned northern village, and gratefully fill their tanks with it.

[ontherocks83]

Originally Posted by hamburking

The diesel fuel itself will last for many years. The trouble is contaminants...like a "bloom" or rust chips, or sediment. Filtering is prudent.

I recall the book NORTH TO THE NIGHT they find a barrel of diesel in an abandoned northern village, and gratefully fill their tanks with it.

I know the contaminants are a killer but does modern day/new diesel "gum up" like gasoline? Obviously not counting contaminants just the diesel going in clean in a sealed container.

[S/V Alchemy]

Originally Posted by a64pilot

Old Diesel if stored correctly would last almost indefinitely, I believe in some places there is Diesel left from WWII still being used, but I can't confirm that.
Newer ULSD won't last as long, but two years in an air tight container? I'd burn it without hesitation, I bet many boats have Diesel older than that in their vented tanks

"bugs" I have seen, look like snot, you can't miss it

I wouldn't hesitate to burn such diesel, either.

I have seven year old diesel in vented tanks I have been happily burning since I put in a filtering setup. Two points, however: I did have a bit of gunk at the pickup tube, and I did have "real" diesel, uncut with ethanol. The story is here: The world encompassed: These fuelish things, revisited

[Scout 30]

My neighbor had a fuel polishing company out to his house & I talked to the operator about old diesel. He said age is not an issue. They run the fuel through a water separator & 30 micron filter with a high powered pump when they polish it. The difference with new diesel is it's ultra low Sulphur which means there is less lubricity. However, the new diesel is supposed to meet a minimum lubricity rating so a synthetic additive usually replaces the Sulphur.

[moseriw]

What I ment is: you should know about the ingredients of your diesel. I do not know US-Standards but I know that european diesel is a pest!

Diesel Fuel Test Kit | Fast & easy test for Diesel contamination

[reed1v]

Answer is it will last longer than your boat will. We filled our boat down in Palmyra from old WW2 diesel tanks back in the late 80s. So almost 50 years old and still good to go. Obviously you filter it, but otherwise it will last many many decades. Diesel can get contaminated with water, molds, fungi, and debris but all that can be filtered out with a simple Baja Filter and common sense.

[Emouchet]

Every year, when my diesel tank is getting low, before I fuel up again, I empty first my spare plastic drum into the main tank.
This allows me to 'refresh' diesel in the plastic drum every year, and burn the one year old.