Using used oil in the fuel ?

[DJb]

I've heard that sticking in a gallon of used oil in a full tank of fuel is ok... also heard it's not. What's the story? Your opinions please.

 

[nickleinonen]

regular dino engine lube oil will burn pretty well in a diesel engine, but it needs to be filtered well before dumping it in... and it is also best to only do so on older mechanically injected [inline & rotary pumps] engines... cummins actually has a system that takes crankcase oil and automatically puts it in the fuel tank to be burned [and either automaticallty adds new lube oil to sump, or operator does so in daily checks] i believe the system is called centenial or something like that... now if i had an old vw diesel or a 1st gen dodge, i'd burn the waste oil in them, but with a newer engine, and with synthetics being popular [they don't burn so good] i wouldn't do it

 

[DJb]

Thanks for the reply. I have a 92 and a 97 Cummins... . wouldn't it be ok in the 97 engine too since it's still has a mechanical pump? This topic came up on another board and after reading about it there, I thought I'd come here where there are more people in the know about matters such as that.

 

[JLEONARD]

I know of a few boaters who burn their drain oil in their 12V P Pumped Cummins engines. They keep the ratio to a low % , but I don't remember what it was... . I think like 5%

Hope this helps.

Jay

 

[Vaughn MacKenzie]

I have been burning the oil from my last change in my '96. Only doing 2 quarts per tank since it's winter, I would not put more than that in this time of year. In summer a gallon max.

No increase in smoke noted, either blue when cold or black when warmed up.



Vaughn

 

[keimmmo]

I have burned waste oil in my old 92 for over 300,000 miles... no problems that I can see. I have even burned it in the 01. 5 for over 100,000 miles... no problems there either. I consider it to be cheap fuel!



Yes, filter it as best you can or you will replace more fuel filters. Consider adding a prefilter if you are going to burn it all the time. Limit how much you add to the fuel in cold weather.



The old 92 raises so much smoke I can't stand it if I put over 2 qts in a tank. The 01. 5 can swallow a gallon per tank and doesn't smoke a bit. Dino oil burns fine... as well as most synthetics if used in small amounts. I have tried burning Amsoil and that stuff drips out the tail pipe instead of burning! It killed both my power and my fuel economy! Live and learn.



Steve

 

[John - K5AWO]

I have a 98 24 valve and in the summer I run waste oil 50/50 with diesel and have not had any problems what so ever. The oil from my Cummings just goes in the tank, all of it.



Waste oil I pick up from other places gets mixed 50/50 with diesel to thin it down and then I filter it down to 2 microns. Then it goes in the tanks. When I can't get any used oil, I throw in about 6 ounces of Marvel Mystery oil per 30 gallons of diesel.



The truck has more power when I add oil and it is quite noticable. In the winter here in Phoenix, I don't go over about 25%. The only down side I see is the tail pipe runs sooty black when using waste oil.



If I loose my waste oil source (used aircraft engine oil and it's clean), I will just go back to veggie oil and run it thru my silica beads I bought from Hydrogen Appliances.

 

[Headshot zod]

John, how are those beads? I've been looking at them for quite a while.

 

[hammersley]

How do you guys filter this stuff?????

Do you use a gravity system or how do you filter the oil before putting into tank?????? I mean fo the price of diesel can't tou just go to a place like jiffy lube and or wally's and pump out some... I know they probably have a contract BUT if you could get say 55 gallons per month and run it say 1/2 gallons per tankful - would help lower cost of fuel?????

 

[keimmmo]

I have read that Cummins recomends a maximum of 20% oil in the fuel. I rarely go over that, but I push it hard on the 01. 5. I wouldn't have the nerve to go 50/50!



Steve

 

[John - K5AWO]

Do you use a gravity system or how do you filter the oil before putting into tank?

I use an electric fuel pump I bought from AutoZone, the small one. They have two sizes. Use it as a suction pump thru the filters. . I start with a engine oil filter for the trash and dirt. End up going thru a sediment filter you can get at a hardware store. They are usually white and go in a standard water taste filter setup like for a reverse osmosis system.

 

[Vaughn MacKenzie]

I'm bad and don't prefilter mine. Let it set a few days, then dump all but the last pint into the tank. I figure since the oil was circulated through the Stratapore it should be pretty clear of all but fine contaminants. And of course I drain into a sqeaky clean bucket then put a lid on it.



50% seems like a lot, oil is a lot more viscous than diesel and it probably stresses the VP44. Vaughn

 

[keimmmo]

Vaughn,



I too have given up on my filter system. It was just too much work. I let the oil set in gallon jugs for as long as possible in a warm place. I too leave a little oil in the jug when I pour it into the tank... but later I pour together all the little bits and let it settle out and use it too. That is why I use a 2 quart pre-filter on my truck!!! However, I guess I'm not dumping too much crud into the tank since I change filters based on my fuel pressure and often go 25k on a pair of filters!



I have found that you can run really heavy on the oil if you are using 5W-30. The thinner the oil the more you can use. I burn mostly 15W40 and 20W-50 oil. I don't go over 20% on it!



Steve

 

[John - K5AWO]

Vaughn, I don't do any prefiltering IF the oil came out of my CTD's crankcase. That is a known quanity although it sure can't hurt anything to filter it.



The prefiltering I was referring to is from used oil I have obtained from other sources where I don't know the history. There, I want to make sure there aren't any carbon granules running around in the oil.



I think you would all find it much easier to filter/strain/settle the oil if you premix it about 50/50 with diesel first. That thins it way down and it filters much better. The solids would fall out quicker, especially if the oil is kept warm. Or, it would filter much easier if you filtered it right away. I prefer the settling process and then filtering it.



I have installed two nipples in the side of my filtering barrel. #1 is on the bottom, and #2 is up about 8 inches from that. I drain it every so often from the bottom valve and dump that at Autozone. I pull what I want to use from the upper valve.



John

 

[Vaughn MacKenzie]

That's a good thought John, premix it with diesel first, especially if it didn't come from your own truck.



My brother has several gallons of oil in a barrel he's collected from his vehicle oil changes. I'm about ready to offer to take it off his hands



Vaughn

 

[JHerrlich]

This is from Cummins and applies to the ISB:



CAUTION

Do not blend more than 5 percent used lubricating oil with the fuel. Do not blend other used oils with fuel, such as transmission fluid, gear case oil, and so forth.

 

[Uncle Rupe]

waste Oil

I had an old friend who was a Dodge lover. He bought a new Dodge car about every five years. He used to put waste oil from his new Dodge in gallon jugs and let them stand until the heavy stuff settled out. Then he would use that in his "old" Dodge. It seemed to work for him, but I dont know about the additives that might be missing or depleted. Guess it doesn't matter as he didn't put many miles on either car.

What are the pro's and cons in burning used oil in a Cummins?

 

[HOBrian]

Can you use this type of fuel for the 3rd gen trucks?????

 

[ProMac1K]

Cummins calls that CENTINEL, an advanced oil managment system that extends your oil change intervels by putting a small amount of crankcase oil in the fuel system, and then replenishing the oil taken from the crankcase with new oil. Their quoted extended oil change intervels look very appealing.



http://billgatliff.com/~bgat/articles/centinel/t1.html



http://www.marinelink.com/may97/mr0507.html



Trever

 

[ProMac1K]

Oh, it is being used on the larger fleet engines.



Isn't there a fine for that? :--)