I have some diesel fuel that is about 3 years old. It has been sitting in a auxilary tank in the shed in the yard for all this time. It has been sitting out there through 3 Phoenix summers with temps up to 118 deg. But it has not been subjected to any water and very little humidity. It also had PRI-D added to it when it was first put in the tank. If I look in the tank with a flashlight, the fuel still looks yellow/clear pretty much the way it looked when it was put in the tank. Is this fuel still useable? Could it screw up my injectors or injector pump?
What bad things can happen when using old diesel?
- Thread starter k1rod
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JHZR2
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No growth in there? It may have lost some energy content, and some of the lower volatiles may have flashed off, making the flashpoint slightly higher (natural distillation).
Id just upgrade with a good healthy dose of power service or similar - one of the performance variants that gives the cetane boost and all.
Diesel should have a 1-2yr spec storage life, so Ill bet youre OK.
Id just upgrade with a good healthy dose of power service or similar - one of the performance variants that gives the cetane boost and all.
Diesel should have a 1-2yr spec storage life, so Ill bet youre OK.
I would give it another dose of biocide, a healthy splash of Diesel Kleen and use it up. Cut it 50/50 with fresh fuel if you have any suspicions about growth or free water.
My Peterbilt sat 20 years. Drove it home on the old fuel. Seemed fine.
Don't put biocide in the fuel as it is too late, it only works before not after storage and some injection systems don't like it.
Best thing is to buy a cleanable pre filter or even make one, then drain the tank into some clean cans through the filter. A good pre filter will even stop water, although if you don't use the last part of the tank that will solve that issue.
I used to use a pre filter with 3 removable screens inside a funnel that I bought from Westmarine and it saved me a lot of fuel filters over the years.
3 year old diesel will be fine as long as you filter it first, the bad stuff will be in the form of water or a nasty brown mud like slime at the bottom of the tank.
Best thing is to buy a cleanable pre filter or even make one, then drain the tank into some clean cans through the filter. A good pre filter will even stop water, although if you don't use the last part of the tank that will solve that issue.
I used to use a pre filter with 3 removable screens inside a funnel that I bought from Westmarine and it saved me a lot of fuel filters over the years.
3 year old diesel will be fine as long as you filter it first, the bad stuff will be in the form of water or a nasty brown mud like slime at the bottom of the tank.
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Originally Posted By: skyship
Don't put biocide in the fuel as it is too late, it only works before not after storage and some injection systems don't like it.
Every biocide I've looked at (and granted, I am not a connoisseur of biocides - never had to use one myself) has always listed a 'shock' (1 - 3 hour) treatment as one option.
Dosing while filling the tank and periodically afterwards is always preferable, but you absolutely can use biocides after the tank is filled.
Running the diesel through a prefilter is an excellent idea and it will give you a quick idea of how much contamination is present, if any. However I bet with the heat and low humidity you won't have any growth problems.
Don't put biocide in the fuel as it is too late, it only works before not after storage and some injection systems don't like it.
Every biocide I've looked at (and granted, I am not a connoisseur of biocides - never had to use one myself) has always listed a 'shock' (1 - 3 hour) treatment as one option.
Dosing while filling the tank and periodically afterwards is always preferable, but you absolutely can use biocides after the tank is filled.
Running the diesel through a prefilter is an excellent idea and it will give you a quick idea of how much contamination is present, if any. However I bet with the heat and low humidity you won't have any growth problems.
we had 1500 gallons that was 10 years old. The only problem we had running it through tractors was plugged fuel filters.
Nothing extreme like new filters every tank or anything. There was a little inline pre filter that would fill up every few hundred gallons and we started back flushing it instead of replacing it. and then finally before the fuel was all used up we had to put on new main filters.
To my knowledge this fuel wasn't pre or post treated with anything. The bulk fuel tank pump of course had a filter also, and we changed a few of those. And this bulk tank was an outdoor above ground setup.
Nothing extreme like new filters every tank or anything. There was a little inline pre filter that would fill up every few hundred gallons and we started back flushing it instead of replacing it. and then finally before the fuel was all used up we had to put on new main filters.
To my knowledge this fuel wasn't pre or post treated with anything. The bulk fuel tank pump of course had a filter also, and we changed a few of those. And this bulk tank was an outdoor above ground setup.
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If you clean the tank before use and keep it full there is no need to add biocide to stored diesel fuel, BUT once the tank is dirty or water gets in then the brown stuff starts to grow. Most good diesel has a small amount of biocide in it and it stores quite well for some years in a good full storage tank.
Much depends on what you are going to put it in. A 20 year old non injector engine won't care much. A common rail needs extremely clean diesel.
Particles you can see aren't a problem, since any filter will get them out. It is the 5 to 15 micron particles that will get past and kill the injectors.
This is clean diesel in a microscope. The green line is about 80 microns.
This is typical diesel from a storage tank.
This is what I see in many on-board diesel tanks, since none have filters on their respirators (consume 50 gallons of diesel, suck 50 gallons of dirty air into the tank from under the wheels)
BTW, the last two were from two 6 month old armored cars that had broken down on the road.
Particles you can see aren't a problem, since any filter will get them out. It is the 5 to 15 micron particles that will get past and kill the injectors.
This is clean diesel in a microscope. The green line is about 80 microns.
This is typical diesel from a storage tank.
This is what I see in many on-board diesel tanks, since none have filters on their respirators (consume 50 gallons of diesel, suck 50 gallons of dirty air into the tank from under the wheels)
BTW, the last two were from two 6 month old armored cars that had broken down on the road.
I would get several opinions from diesel drivers, filters, bad fuel, been thru that with my son on his 18 wheelers, can turn into nightmares, get new filters, new fuel , downtime is a u know what ,but he has his own rig and bad maintenance is not in his vocabulary.
The car does have injectors but it is not a Common Rail. It is a 2001 VW TDI with an ALH engine. I think I should be OK with particulates. I did a modification on this car that involves removing the OEM fuel filter and replacing it with A Caterpillar 2 micron High Efficiency filter (1R749). The filter has huge capacity also with some folks reporting going 100k miles on them. Thanks for the pictures! I guess fuel can get pretty nasty.
k1rod, it depends on how bad the fuel is and what you intend to use it in, and how much you have vs. the costs involved. You can always polish the fuel, pumping it through a filter before you consume it. Racor offers filter elements rated at 2 micron, 10 micron, and 30 micron (for winter). If you can filter the fuel through the 2 micron filter, it won't physically damage the injection parts. You can find somebody to polish the fuel, or rig up your own pump and filter, or even use gravity flow through the filter. It might not burn very well, so mixing with good fuel is smart. Or, just give the fuel away to anyone using heating oil in a burner.
Ken, That's kind of what I'm thinking. 2 micron filtration with a good slug of Power Service for lubricity and Cetane (as recommended by JHZR2). But since I already have a 2 micron fuel filter in my car, would there be anything to be gained by polishing the fuel before I put it in my tank? I have about 150 gallons and at $4.25 a gallon now, that's almost $640 worth of fuel I'd be tossing if I disposed of it (if I could even figure out the proper way to do that). Nobody here in Arizona has oil heat. Pretty much all electric heat pumps. Thanks all for the insight so far.
Originally Posted By: k1rod
The car does have injectors but it is not a Common Rail. It is a 2001 VW TDI with an ALH engine. I think I should be OK with particulates. I did a modification on this car that involves removing the OEM fuel filter and replacing it with A Caterpillar 2 micron High Efficiency filter (1R749). The filter has huge capacity also with some folks reporting going 100k miles on them. Thanks for the pictures! I guess fuel can get pretty nasty.
You left out the "0" in that number. It is 1R0749, or Donaldson's P551311. I've been putting that on dozens of small trucks here and have two dealers that install them before delivering the trucks. You may fill it up with your old diesel, but that will do the trick as long as it isn't common rail.
That 2 micron is an "absolute" rating. It is about 3 um at 99%.
As for Racor, consider that the numbers they publish are "nominal" (Beta 2, 50% efficiency). Be careful when comparing apples to bananas.
The car does have injectors but it is not a Common Rail. It is a 2001 VW TDI with an ALH engine. I think I should be OK with particulates. I did a modification on this car that involves removing the OEM fuel filter and replacing it with A Caterpillar 2 micron High Efficiency filter (1R749). The filter has huge capacity also with some folks reporting going 100k miles on them. Thanks for the pictures! I guess fuel can get pretty nasty.
You left out the "0" in that number. It is 1R0749, or Donaldson's P551311. I've been putting that on dozens of small trucks here and have two dealers that install them before delivering the trucks. You may fill it up with your old diesel, but that will do the trick as long as it isn't common rail.
That 2 micron is an "absolute" rating. It is about 3 um at 99%.
As for Racor, consider that the numbers they publish are "nominal" (Beta 2, 50% efficiency). Be careful when comparing apples to bananas.
Thanks Richard for the correction on the part number. Your post got me wondering what more you would have to do to make this fuel useable in a common rail system. The only better filtration I know of is sold by a company called Nicktane which advertises 1 micron synthetic media filters.
I've got one of Nicktane's filter heads on my Golf (also had one on the NB we recently traded) but with the pipe nipple for the Caterpillar 1R0750 2µm fuel filters instead of his 1µm synthetic glass filters. Excellent value and very well made!
Originally Posted By: scurvy
I've got one of Nicktane's filter heads on my Golf (also had one on the NB we recently traded) but with the pipe nipple for the Caterpillar 1R0750 2µm fuel filters instead of his 1µm synthetic glass filters. Excellent value and very well made!
Nicktane (Nick) makes a nice filter set up. I have one of his in my Silverado. It uses the 1R0749. The set up I have in my VW TDI was from Lubrication Specialists. It uses the 1R0750 which is really the same filter as the 1R0749 except a bit shorter.
I've got one of Nicktane's filter heads on my Golf (also had one on the NB we recently traded) but with the pipe nipple for the Caterpillar 1R0750 2µm fuel filters instead of his 1µm synthetic glass filters. Excellent value and very well made!
Nicktane (Nick) makes a nice filter set up. I have one of his in my Silverado. It uses the 1R0749. The set up I have in my VW TDI was from Lubrication Specialists. It uses the 1R0750 which is really the same filter as the 1R0749 except a bit shorter.
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