How old is too old....for diesel in the tank?

[dtrvler]

Just got a 2000 Beetle tdi that sat for 5 yrs with 7/8 of a tank of clean diesel in it. Its still clear and smells just like new diesel. It was sitting at 6,000 ft so it stayed pretty cool which is very important for storing fuel. I dont know if there were any additives other than what the diesel retailer put in it. Anyway, i read about 20 yr old diesel running just fine when in the cool mountains in the woods which is where this one was stored in the cool shade. What do you think? Of course, new filter is mandatory. I thought id drain 8 or 10 gallons out and put new diesel in the parts cleaner....and put some fresh fuel in the car...and prime the system....add some additive...but id bet it would run fine.

 

[turbodieseldyke]

I bet it's just fine. i had a 95 civic start and run no problem after sitting 7 years with 1/4 tank of old gas. Diesel is a far more stable fuel. The only thing i'd worry about is if water got in, and settled at the bottom.

 

[Drewser]

And here I was worrying about 6 month old fuel in the project car I bought... Sweet.

 

[Mongler98]

i have never had fuel go bad but the max is about 3 years storage for me.
If i know im going to store it long term i put in a antibacterial additive

 

[dtrvler]

A little background info:
The guy bought an ebay inferior (and that is being very diplomatic) "timing belt" that he said he saw a "defect" in but used anyway because he "forgot" about the "defect". It lasted 2k miles.
Then the car got towed and and sat in the shade for 5 yrs. I pressure washed the engine etc and under the oil and grime was a brand new looking engine. The oil protected the various metals.
Needs the normal stuff...vac lines, filters, head, tbk. Three key remotes, everything i can tell about on a non runner works. Ill report back after i get it running but i am hoping for this:

 

[oilhammer]

The fuel is fine. I would probably replace the fuel filter once that tank of fuel has been run through, though, just in case something "grew" in the tank but I doubt it did.

We have had diesels here sitting much longer than that. I helped a guy get an old IH grain hauler truck started after sitting for 22 years. We hand cranked the engine around a few times, sprayed some WD40 down the intake port into the head, put fresh batteries in it, pumped the primer on the injection pump until it was stiff, and that big DT466 fired right up with a glorious puff of smoke and ran perfectly.

And I am pretty sure the '75 240D my brother and I bought had been sitting much longer than that. Maybe as long as 30 years.

 

[jettawreck]

I would be concerned with the amount of valve train/head damage after the TB "event" than the old fuel. Hopefully the head is coming off for a refurbishment before anything gets started up.

 

[nokivasara]

I have run a mk2 Golf with 30 year old diesel! It wasn't even diesel but oil for heating a house, it's pretty close to diesel and the Golf didn't mind it at all.

 

[JohnTF]

I've worked on heavy equipment , besides cars & trucks and started stuff that sat for decades .
Too many unknowns as some mentioned above , but several biggies , how much air the fuel is exposed to , and water / condensation .
Same with aircraft - what should be done is when aircraft is done flying , fill tanks [ keep air out ] part of the reason is condensation builds up with air space in tank leaving water to gather in tank --- that why in a preflight check , one of the things you do is to use a tools that plugs into the bottom of the fuel tank to check for water .
Too bad we do not have with cars & truck [ tight squeeze ] water & air are what starts algae & mold growth .
So diesel does not go bad - but bad things can happen to diesel ;(

 

[dtrvler]

I would be concerned with the amount of valve train/head damage after the TB "event" than the old fuel. Hopefully the head is coming off for a refurbishment before anything gets started up.

Read post #5. New head and tbk def

 

[GlowBugTDI]

My car sat for 5 years when i bought it, and it started just fine. Drove it to town and put neew fuel in after it was mostly empty. Did this after the TB was done of course

 

[mozark]

Diesel is very resilient, as pointed out above. I pulled an 85 Mercedes 300TDI Wagon out of a pasture that I had parked it in nine years prior. After replacing a bad battery cable it started immediately. (The ant colony in the spare tire well was much more problematic!)

 

[jmodge]

You’re never too old........ for diesel in the tank