50% used motor oil 50% diesel - Page 2 - PeachParts Mercedes-Benz Forum

Hatterasguy · #16 07-19-2006, 03:49 PM

These engines are nut ment to burn bunker fuel. I'd only do this to a complete junker with one foot already in the grave.

Panzermann · #17 07-19-2006, 03:53 PM

I just don't understand why you'd really want to run used motor oil in your car. 8 qts is 2 gallons. 2 gal of diesel fuel cost max $7, maybe in California. Using such oil as fuel (1) might cause damage to your engine (see notes above) (2) is probably not good for your fuel filter and (3) certainly cannot be good for the environment (though the amount of bad may be debatable).

Now, I read in National Geographic of a diesel truck driver in the middle of the Sahara Desert in Niger who ran out of fuel and was about to die of thirst, but realized that he could drain the oil from his truck's crankcase and use it for fuel to save his life by driving to a place with water, but (1) I'm sure it didn't do his engine much good and (2) the benefit of burning crankcase oil clearly outweighed any possible damage to the environment.

On the other hand, to save $7 in fuel, while risking a Mercedes engine at all seems "Penny-wise and Pound(Dollar) foolish," particularly when a collection/recycling system is set up to collect such oil to prevent environmental contamination of any sort.

If you want to burn fresh motor oil, I guess you can, but it certainly does not make much economic sense, given that the lowest price you're likely to get is about $1 a quart, and the price is likely to fluctuate in parallel with the cost of diesel fuel. The idea of using unmodified soybean oil, which you can get at Costco for about $2.75 per gallon, seems to make much better economic sense, is probably OK for limited use in your engine (especially if mixed 50/50 with #2 diesel fuel), and probably would be GOOD for the environment.

A tank of fuel that I had in a 300D got contaminated with a bit of used crankcase oil (just a little bit that was at the bottom of the cannister I used to get some fuel in; I thought it would not be a problem at all). It smoked like crazy until I drained the tank and replaced it with fresh fuel, so I have to disagree with the posts indicating that used motor oil burns fine. It was a mess to deal with (draining the tank and replacing the fuel) and I would not let that error happen again (unless of course I was caught in the desert in Niger and had run out of fuel and was dying....)

85chedeng300D · #18 07-19-2006, 08:26 PM

fueling with used motor oil with all the tiny unfiltered metal dust particles 50/50 with diesel?

well, good for you!!! with the sky high fuel prices, your're saving the environment by saving 50% of diesel fuel each fill up! and by the way, it's a good thing too, you are honing the cylinders while driving!

blueranger · #19 07-19-2006, 09:03 PM

get an old pair of blue jeans at a yard sale for 1 dollar.

cut the legs off and close the ends with wire ties... pour the oil through it..

let it sit over night... wala 1micron filter bag..

then just pour it in your tank... use what ever ratio you want..

after all om617 stands for oil motor

Carleton Hughes · #20 07-19-2006, 10:07 PM

Quote:

Originally Posted by 85chedeng300D

fueling with used motor oil with all the tiny unfiltered metal dust particles 50/50 with diesel?

well, good for you!!! with the sky high fuel prices, your're saving the environment by saving 50% of diesel fuel each fill up! and by the way, it's a good thing too, you are honing the cylinders while driving!

No, he's grinding them

P.E.Haiges · #21 07-20-2006, 02:26 AM

Think about it: Why wouldn't all the metal particles and soot grind up the engine when it goes thru millions of revolutons when the oil is in the engine crankcase and pumped thru the engine and sprayed into the cylinders? How will used engine going one going thru the engine one more time hurt the engine?

Possible it could damage the IP or injectors, but I've been using a small percentage of used engine(~2%) with no bad results. With the ULSD Diesel fuel, the used engine helps to lubricate the IP.

But 50 % is way to high a percentage. It will carbon up the engine inside. I had an old 190D engine that had a crack in the head that leaked engine oil into #1 cylinder so it used about 1 quart of oil every 150 miles. When I took the head off, the #1 piston and inside of the cylinderhead were thick with burned carbon and I imagine the pre-chamber was too.

150 miles per quart is about a 20% concentration of engine oil going to the 1 cylinder that leaked. That's too much in my opinion. I can't believe that there was no blue smoke with a 50% concentration because my old 190D smoked a lot because of the oil leak.

P E H

bnaquin · #22 07-20-2006, 02:43 AM

Quote:

Originally Posted by blueranger

get an old pair of blue jeans at a yard sale for 1 dollar.

cut the legs off and close the ends with wire ties... pour the oil through it..

let it sit over night... wala 1micron filter bag..

then just pour it in your tank... use what ever ratio you want..

after all om617 stands for oil motor

Another option might be attaching magnets to the filter and several stages to catch those pesky metal bits. I do this in my differentials and the magnets work great.

brabus · #23 07-20-2006, 04:35 AM

Quote:

Originally Posted by P.E.Haiges

Think about it: Why wouldn't all the metal particles and soot grind up the engine when it goes thru millions of revolutons when the oil is in the engine crankcase and pumped thru the engine and sprayed into the cylinders? How will used engine going one going thru the engine one more time hurt the engine?

Possible it could damage the IP or injectors, but I've been using a small percentage of used engine(~2%) with no bad results. With the ULSD Diesel fuel, the used engine helps to lubricate the IP.

But 50 % is way to high a percentage. It will carbon up the engine inside. I had an old 190D engine that had a crack in the head that leaked engine oil into #1 cylinder so it used about 1 quart of oil every 150 miles. When I took the head off, the inside of the cylinderhead was thick with burned carbon and I imagine the pre-chamber was too.

150 miles per quart is about a 20% concentration of engine oil going to the 1 cylinder that leaked. That's too much in my opinion. I can't believe that there was no blue smoke with a 50% concentration because my old 190D smoked a lot because of the oil leak.

P E H

You know this all sounds very logical, I just wanted to try it more than anything. It's not like i have a source for oil anyway. It was a lot better than draining it in the creek like i usualy do.

Just joking. I always take my used oil to autozone.

P.E.Haiges · #24 07-20-2006, 10:50 AM

brabus,

I wonder if AutoZone would give some of the drain oil they collect back to me? Its worth $3 a gallon replacing Diesel fuel.

P E H

#25 07-20-2006, 11:27 AM

Quote:

Originally Posted by P.E.Haiges

brabus,

I wonder if AutoZone would give some of the drain oil they collect back to me? Its worth $3 a gallon replacing Diesel fuel.

P E H

I'm sure they would love to sell their hazardous waste to unlicensed individuals for use as untaxed road fuel. No problem at all.

rg2098 · #26 07-20-2006, 11:38 AM

I run 1-2 gallons per tank full of diesel regularly. It gets filtered down to 1 micron and I know where the stuff came from instead of sitting in jugs who knows where. I feel no difference in power or smoke at those levels and it boosts my perceived mileage up to a bit over 30 mpg.

ConnClark · #27 07-20-2006, 11:46 AM

There is a reason you removed the oil from your engine in the first place. Why put it back?

Quote:

P.E.Haiges
Think about it: Why wouldn't all the metal particles and soot grind up the engine when it goes thru millions of revolutons when the oil is in the engine crankcase and pumped thru the engine and sprayed into the cylinders? How will used engine going one going thru the engine one more time hurt the engine?

When oil flows in an engine its all below the piston rings and the soot and metal particles get washed away. When you burn the used motor oil its above the rings and when the oil burns it leaves the metal particles behind. Do to your engine what you want but don't say we didn't warn you.

IndianaJo · #28 07-20-2006, 05:27 PM

I burn 1 quart of used motor oil per tank, no problems yet. I do let it sit for a month or more to let the water and sludge settle to the bottom, I donate that to the service station. I also run a 20 micron Goldenrod 495 fuel filter instead of the tiny, forever stopping up, primary Mercedes/Bosch fuel filter. Sunflower filters are available from the farm supply, for pumping fuel out of private tanks. They have a water separator bowl, and a real water drain like a Model A used to have. If you install one, use metal lines with not too much rubber hose. I hung the 495 filter from the passenger shock mount bolts.

P.E.Haiges · #29 07-20-2006, 08:26 PM

Conn,

"Tiny metal particles get washed away". Yes, right back into the oil and thru the engine unless they are trapped by the oil filter. So if they are trapped by the oil filter, they are not in the drain oil.

The tiny metal particles, if any get into the cylinders after filtration, will go out with the exhaust.

P E H

P.E.Haiges · #30 07-20-2006, 08:29 PM

Craig,

I don't want to buy the used oil, I want it for free.

P E H