What creates "bad diesel" fuel ?

[Hermio]

I tried off-road diesel once. $.30 less per gallon. Tractor didn't like it and I think it was water contaminated. The filter replacement that year was interesting, usually it's clear and clean with road diesel. I'm only buying 5 gal at a time in my scut so $1.50 extra per fill-up is cheap insurance for smooth running

It may be that the off road pump does not have as much turnover as the normal pump, resulting in more water, etc.

 

[Hermio]

One bulk plant here was selling bio diesel and not telling anyone. The buyers had problems and couldn't figure out why. Once the customers figured the plant out, they bought somewhere else and problems went away.

Odd. Biodiesel is more expensive than petro diesel.

 

[Richard]

Not a good idea to add fresh fuel to old fuel when the tractor tank is half full.

May I ask why?

I've always had the thought (and therefore practice) of filling my tanks when I'm done for the day, this way I:

1. Always start the next time with a full tank of fuel
2. Keep tank full, most of the air out.
3. When I fill the tanks on the machine, they're full. I can now go to the co-op and replace them giving me a full compliment of fuel for whatever is ahead of me. (I really hate running out of fuel, going to Co-op for 40 gallons, fill tractor, go BACK to Co-op and get another 40 gallons, put 20-30 into my backhoe, go BACK to the Co-op and finally get things topped off.

I much rather try to stay ahead of that game and keep machines full AND my 5-gallon tanks.

Note, if it matters, I've got metal/steel fuel tanks on tractor and backhoe. My understanding is if you get things warm, put it away, as they cool down they can draw in moisture from outdoors and this can condense inside the tank, giving you the very issues you are trying to avoid.

Not saying this is right, just what I've read.... so what's the other point of view of leaving the tank at x% of full when your done?

 

[coobie]

I was the laboratory manager for a small refinery in Kern County, CA for a number of years. Let’s clarify some things first. Each and every sales tank at any refinery in the US has an accompanimg signed data sheet showing that the product has passed the required ASTM tests for that product. Red diesel is just diesel colored red for road tax determination purposes.

The second point I would like to make is that diesel is a “wet” fuel, it’s a fraction that contains water. Being a wet fuel means that measures need to be taken to keep it dry, as it is when it leaves the refinery, microorganisms love wet fuels. This includes algae and bacteria.

My third point is that to your surprise there are two sources of diesel, paraffinic and asphaltenic. Paraffin based crudes produce a yellow sweet smelling high cetane fuel but with a rather high pour point grade #2 And #1 grade which has a much lower pour point. Asphaltene based crudes are cracked to make a product that resembles root beer color and has a bad odor. They are low cetane and have to be chemically boosted.

The third concern is sulfur which is now being reduced in diesel to 15 ppm and it promotes microbial growth and particulate formation.

So what are the issues with diesel fuel, paraffin (wax), asphalt - ugh and sulfur also an ugh and water. I would avoid dark asphaltenic diesel if at all possible. Number 2 diesel is great, when dry, but not in colder climates. Number 1 diesel is more highly refined a has a low pour point.

There is also a third diesel - marine diesel which is thick and waxy.

Depending upon the diesel you use choose the best additives if needed, keep your tanks full to avoid condensation, drain you water separators often, use #2 only in warm climates and use a fine filter screen when filling your tanks. If you do see or feel a scum if it light color and smells like diesel it is most likely wax but if it’s foul smelling it’s probably microbial.

Are you trying to say avoid red dye diesel in cold climate ??

 

[dcarman]

Several years ago I experienced a summer of "frequent" fuel filter changes. On the T1530 NH that I cut several fields with I had to change the filter often. The machine would just not maintain power & speed. After the filter change it would immediately be back to spec.
I was buying my diesel at the same location that year and when I finally decided that my filter issues were caused by the fuel I was using I changed to another source ................. and the issues went away. I've only changed the filter once in the last two years and the symptom is the rpm drop & power loss.
I'm suspicious that something in the fuel "coats" the filter. Anyone else have similar problems ?

Diesel fuel does not go bad like gas can. I have used diesel fuel that is 30+ years old without issue. However - Kerosene based fuels like diesel and jet fuels (wide cut fuels that include Kerosene) can be up to 7% entrained water. This gives bacteria the opportunity to grow and multiply in your tank or your suppliers tank. Warm summer days can help the bacteria to propagate. A product like BIOBOR JF should fix the problem. If you have a supplier selling you contaminated fuel they need to know as they may need to treat their tanks also.

 

[RalphVa]

Probably not hydrodewaxed, just solvent dewaxed, and the pour point depressant didn't work on the hydrocracked stuff.

Sorry. Didn't think. Don't think any diesel is solvent dewaxed. Their pour point depressant just didn't work.

 

[Tony H]

Algae. Today's low sulphur fuel allows algae to form. So not only do you have to pay way high prices for this Gasoline by-product because they have to reduce the sulphur, BUT you have the added expense of putting a Biocide in the fuel tank.

 

[ovrszd]

I tried off-road diesel once. $.30 less per gallon. Tractor didn't like it and I think it was water contaminated. The filter replacement that year was interesting, usually it's clear and clean with road diesel. I'm only buying 5 gal at a time in my scut so $1.50 extra per fill-up is cheap insurance for smooth running

This is typical. Your problem was fuel quality, not color of the fuel.

 

[priberc]

I was the laboratory manager for a small refinery in Kern County, CA for a number of years. Let’s clarify some things first. Each and every sales tank at any refinery in the US has an accompanimg signed data sheet showing that the product has passed the required ASTM tests for that product. Red diesel is just diesel colored red for road tax determination purposes.

The second point I would like to make is that diesel is a “wet” fuel, it’s a fraction that contains water. Being a wet fuel means that measures need to be taken to keep it dry, as it is when it leaves the refinery, microorganisms love wet fuels. This includes algae and bacteria.

My third point is that to your surprise there are two sources of diesel, paraffinic and asphaltenic. Paraffin based crudes produce a yellow sweet smelling high cetane fuel but with a rather high pour point grade #2 And #1 grade which has a much lower pour point. Asphaltene based crudes are cracked to make a product that resembles root beer color and has a bad odor. They are low cetane and have to be chemically boosted.

The third concern is sulfur which is now being reduced in diesel to 15 ppm and it promotes microbial growth and particulate formation.

So what are the issues with diesel fuel, paraffin (wax), asphalt - ugh and sulfur also an ugh and water. I would avoid dark asphaltenic diesel if at all possible. Number 2 diesel is great, when dry, but not in colder climates. Number 1 diesel is more highly refined a has a low pour point.

There is also a third diesel - marine diesel which is thick and waxy.

Depending upon the diesel you use choose the best additives if needed, keep your tanks full to avoid condensation, drain you water separators often, use #2 only in warm climates and use a fine filter screen when filling your tanks. If you do see or feel a scum if it light color and smells like diesel it is most likely wax but if it’s foul smelling it’s probably microbial.

This is gonna sound dumb to you if you worked at a refinery. But here goes any way. "There is a third diesel ,marine diesel, which is thick and waxy". Is this third fuel also known as bunker fuel?

 

[MHarryE]

My nephew uses at least 500 gallons weekly, off highway of course, with no problem. I don’t have on site storage for my smaller usage so it’s off to town. The 2 places that sell off highway don’t move their fuel fast enough and I go through one water block filter every 200 gallons if I buy off highway. And water separators are 90% efficient so 10% still gets into my equipment. So I buy on highway from the station that moves more fuel and replace my water block filters once yearly. The only off highway I use anymore is from my nephew. I have talked to the station owners who admit they have problems but say they can’t afford to fix - meaning holes in underground storage. I don’t understand why they continue to sell if they know their fuel is contaminated but it’s their business.