Used Oil Question

65284 · #1 03/14/08, 09:31 AM

I was at a neighbour's yesterday and saw him dumping used motor oil into his farm diesel fuel tank. He said he has always added a gallon or so of used motor oil to around 10-15 gallons of diesel, the amount depending upon the temperature, even more in hot weather. He claims it has never damaged any of his trucks or equipment, is a non-polluting way to dispose of used oil, and saves a little fuel. Anyone else do this or have opinions if it's a good/bad idea?

mwhit · #2 03/14/08, 09:42 AM

I don't know if it's a bad idea, but any place that changes oil has to accept used oil so it's not hard to get rid of in a non-polluting way.

Michelle

Forerunner · #3 03/14/08, 09:49 AM

I run heavily filtered used engine, hydraulic and transmission oils in my diesel engines. I run up to 60% in some engines during the summer months.
I run 10-30% in some engines in the winter months.
Some diesels don't like it at all.
It is an interesting concept.
The trick would be to have two tanks and to switch to the heavier fuel after the engine is up to working temperature.
Even better would be to know to set up the compression chamber to burn 100% heavy fuels as Rudolph Diesel originally intended.

A gallon here and a gallon there as you change oils around the farm will do nothing except add lubrication to your injector pump and valves.
However, tempting as it is to just dump that hot oil right in the fuel tank, it is far, far better to store it for a few months to let the heavy sediments fall out of it, then run it through a filter before using it in the engine.

Bearfootfarm · #4 03/14/08, 09:50 AM

It wont hurt anything, but I'd filter it before adding to the tank to get rid of the sludge

65284 · #5 03/14/08, 09:53 AM

Quote:

Originally Posted by mwhit

I don't know if it's a bad idea, but any place that changes oil has to accept used oil so it's not hard to get rid of in a non-polluting way.

Michelle

Correct, but, I change the oil in my vehicles and equipment myself.

Michael Kawalek · #6 03/14/08, 09:57 AM

What I've read on Biodiesel posting sites is that used motor oil can be used, but it contains metal particles, and acids from the combustion waste. To sum it up, I suppose if you have an old beater car or tractor with a simple diesel engine, it's probably not going to hurt it. If you have a brand new Mercedes turbo diesel, I'd say no.

One practical alternative I've also read about is putting some used motor oil in with the vegie oil when making biodiesel. The same washes that clean the biodiesel also clean the motor oil. They caution though not to go past 5-10% because the resulting fuel gets too thick to flow properly through the injectors.

I have a diesel truck myself, but have never put in anything other than regular diesel or storebought biodiesel. I just don't want to be way out in the mountains one night when I find out what running used oil does to the engine.
Michael

mwhit · #7 03/14/08, 10:03 AM

Quote:

Originally Posted by 65284

Correct, but, I change the oil in my vehicles and equipment myself.

So do we. Then we take it jugs of it to the local garage and they have to take it.

Michelle

Macybaby · #8 03/14/08, 10:19 AM

Around here the local garages have to take it too. Last week my husband hauled off several gallons (he saves it up and goes a few times a year) and right next to the dump spout he found a large bucket of wheel weights. Offered $35 and got about 65 lbs of dead soft lead.

He as one happy camper that day!

Cathy

wy_white_wolf · #9 03/14/08, 10:32 AM

Used motor oil has small metal particals in it from normal engine wear. These need to be filtered out to work as motor fuel. Some older and larger engines can handle larger partiles because of the injectors used. Let the particles settle out for a week or so and filter it. I have a friend that puts it in his dodge. He only adds about 1 gallon per fill-up at most. Some engines cannot handle the increased viscosity of the oil.

texican · #10 03/14/08, 10:55 AM

If I had an efficient way to filter it, I might add some to my tractors diesel... but not the truck.

I keep some used oil in 5 gallon buckets... I use it to dip old tools in, and I'll store rusted parts in it, till I can get around to descaling them.

WisJim · #11 03/14/08, 11:07 AM

I would be wary of dissolved acidic compounds, moisture, and metal particles in used oil. I did know a fellow that used it to run his old Witte diesel single cylinder engine that ran his stand-by generator. He let the oil sit in a large tank for a year or so, so particles and water would settle out, then tapped some off midway up the tank, into another tank, filtering between tanks, then re-filtered it before putting it in the engine's tank.

I also use some to moisten some sand in a bucket to stick shovels and other tools in, to clean off dirt and oil the shovel blade.

tamsam · #12 03/14/08, 01:23 PM

Most places will take it and if they are smart they will find a buyer for it. When I worked foe a transmission rebuilder we always sold the used transmission fluid. If I remember we got at times 30 cents a gallon for it. We put whet we got for it into a kitty and had cook outs for the employees. In the winter we burned it in heaters that was built to burn waste oils and the state or some one from the epa would come and test them at the chimney to be sure they were working properly. We didn't know when they were going to come out so we did nothing differently. Sam

mwhit · #13 03/14/08, 02:30 PM

Quote:

Originally Posted by tamsam

Most places will take it and if they are smart they will find a buyer for it. When I worked foe a transmission rebuilder we always sold the used transmission fluid. If I remember we got at times 30 cents a gallon for it. We put whet we got for it into a kitty and had cook outs for the employees. In the winter we burned it in heaters that was built to burn waste oils and the state or some one from the epa would come and test them at the chimney to be sure they were working properly. We didn't know when they were going to come out so we did nothing differently. Sam

Yup. The garage here has a waste fuel furnace so they are more than happy to take it.

Michelle

morrowsmowers · #14 03/14/08, 02:41 PM

I worked for a hospital with two 10,000 gallon oil tanks. They would put used refrigeration oil, etc. back into those tanks. It would be so diluted it probably didn't make any difference.

Ken in Glassboro, NJ

Jim S. · #15 03/14/08, 04:30 PM

Works fine, runs fine, saves a little fuel costs. I have buddies who dump the oil in the tank on diesels after changing it. Been doing it for years. You have to be careful you don't get too much in the fuel, though, or it'll have to be heated to be injectable.

ace admirer · #16 03/14/08, 07:37 PM

diesels have fuel filters,

been running it mixed with diesel fuel for a few decades in tractors. with diesel at almost $4.00 a gallon, i'll be one of the places you can take your little jugs of motor oil to to have it recycled.....

WayneR · #17 03/15/08, 11:25 AM

At last check, the "recyclers" are getting around sixty cents a gallon to take that used oil off your hands. They get paid to sell you new, clean oil then get paid again when they sell the used oil.

This begs the question as to how much longer the public will even be able to buy motor oil, without going to a bonifide "oil exchange" business?