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WEO/WMO in diesel fuel

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  • Owner

Can I get rid of my used engine oil by adding it to diesel fuel?

Adding used engine oil to diesel fuel used to be a common practice. However, it almost

certainly results in a blend that does not meet diesel fuel specifications. One or more of

these properties may be too high: 90 percent boiling point, sulfur content, ash, water

and sediment, viscosity, and carbon residue. A diesel fuel/used oil blend may not be sold

as diesel fuel and we recommend against using it as a diesel fuel.

In California, the addition of used engine oil to diesel fuel is a violation of hazardous

waste regulations. Diesel fuel users in other areas who may consider this practice should

check for any applicable regulations.

This was copied from Chevron Web site... Come to find out it illegal to mix WEO/WMO in diesel fuel in California. Also once again even Chevron mentions that putting WEO/WMO in diesel fuel is a common preactice but suggest away from it. Being of the same problems I been talking about...

ASH CONTENT (Ash cotent is to high!)

Ash - Minor - Can damage fuel injection system and cause combustion chamber deposits. Causes damage in the long term...

CARBON RESIDUE (Blow by gasses / carbon)

Carbon Residue Minor Measures coking tendency of fuel; may relate to engine deposits. Causes damage in the long term...

SEDIMENT (All the wear metals/debris)

Water and Sediment - Minor - Affect fuel filters and injectors. Can cause Immediate filter plugging and/or fuel system damage...

VISOCITY (Too thick)

Viscosity - Bulk - Affects fuel spray atomization and fuel system Immediate and lubrication. It also affects fuel system leakage. Causes damage in the long term...

Cummins Centinel get away from this by keeping the mix ratio of WEO/WMO very low compared to the diesel fuel. Typically less than 5% by volume for WEO/WMO. 5% is roughly 1.75 gallons of WEO/WMO for 35 gallons of diesel fuel. This way the Visocity, Ash, Carbon residue, and debris are controlled and kept to a minimum. This also keeps the burn characteristics of the fuel in a usable range without changing dramatically... ;)

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  • Owner

Currently there is no way to filter ASH or the SOOT (Carbon residue)... So even Cummins will not suggest any amount over 5% of WEO/WMO to be used... This is to control the ASH and SOOT levels in the fuel. Not to mention controlling the visocity... Remember WEO is 100-110 cSt @ 100*F where diesel fuel is about 2-5 cSt @ 100*F. So as winter time get around the fuel will become to thick and might cause injector and pump damage... There is a reason why Cummins set some limits... ;)

I've got a Frantz Filter and it filters down to 1-2 microns easy... But still the oil is very sooty (black) and contains ASH...

Posted Image

I went back and did some reading up on ASH...

This was copied from SAE Standards J313 for Diesel Fuels

5.11 Ash

Ash forming materials may be present in diesel fuel either as suspended solids or soluble metallic compounds. Suspended solids and certain dissolved organometallic compounds containing sodium, vanadium, etc., may contribute to injector, fuel pump, and ring wear and also to rapid deterioration of engine parts exposed to high temperatures such as turbochargers and valves. Soluble metallic compounds may also contribute to engine deposits.

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I am running Shell Rotella synthetic and put a gallon of drain oil in the tank. No net change, I plugged the pump gallons and miles in for mpg and the result is the same as the last 3 with the camper on. Of course when the gallon of drain oil is figured in the number is lower. 17.89 with about 11 square feet more sail and 1900 more #.But then I knew that the drain oil does not burn well, it is useless for burning brush.keydl

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  • 1 year later...

Hey Mike, I realize this is a bit of an old post but I have about 35 gallons of waste motor oil and am wonder what if any new information has been brought out on the subject of burning the WMO in diesel fuel. If there is a safe and user friendly way to filter and burn it, I would be very interested in what others are doing to accomplish this. For guys like me with just 2 cummins diesels that are not used for commercial operation, the Cummins Sentinal would not be cost effective.

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  • 2 months later...
  • 3 years later...
  • 1 month later...

I've got 10 years running on WMO in several diesel engines and spent thousands of hours of runtime testing. Filtering doesn't work as much of the stuff you want to get out is on the order of molecular size. Various additives and metals are put into oil and for LONG TERM RUNNING these should come out. Now you can filter oil and run it for a while, I started that way. After a few hundred hours, I broke down the fuel system and started inspecting parts. I noticed a build up like on the bottom of a piston head. While I noticed no change in the engine performance, I assumed that it was only a matter of time. Now I invested a lot of time in this project and do make filters for this kind of thing. I'm not trying to span the list but here is a paper that I wrote on Waste Oil Running: http://bestcentrifuge.com/running_on_waste_oil.pdf I am happy to answer questions if something is not clear.

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