Question for Diesel experts

Careful34 · #1 09-29-2002, 04:19 PM

Would you be able to run a diesel engine on motor oil thinned with gasoline? Say you had a diesel and the fuel needle was an 1/4" below E on your gauge and no diesel station in sight. Could you mix, say, a gallon of 10W - 30 non-detergent with 2 cups of premium (or whatever, you pick the ingredients and amounts) to get to the next diesel pump? Could the gas and oil be mixed in a proportion so that the quicker igniting gas would start the slower igniting oil to give about the burn time as diesel? Would this combination work if you adjusted the injection timing somehow? If you say it won't work, please explain why.

Also, do you know of any good (and free) diesel engine sites I can check out?

This is a theoretical question for educational purposes only so you don't have to tell me not to try it. I don't even own a diesel at the moment!

[ September 29, 2002, 10:21 PM: Message edited by: Careful34 ]

**Crazy_Jeepman** · #2 09-29-2002, 05:03 PM

I would venture to say yes it would run, I do not know about the mixtures and amounts. I have run out of fuel, and dumped engine oil and fuel additives in the tanks. However there is still a lot of fuel in the tank of a semi even when out of fuel, as the fuel pick ups on most are suspended from the top. Any oil and fuel additives I dropped in were diluted right away and though I had no power mainly from sucking air I made it 3 miles to a truck stop and fueled up 300 gallons. Not very likely 2 gallons of foreign fuel would be a factor with that much fuel

[ September 29, 2002, 11:05 PM: Message edited by: Crazy_Jeepman ]

Glenn_tx · #3 09-29-2002, 05:47 PM

I've heard of industrial size diesels getting what is called a runaway condition becuase of oil leaks into cylinders. The oil essentially becomes the fuel after the injectors shut off.

**Crazy_Jeepman** · #4 09-29-2002, 05:49 PM

Detroit diesels were like that. The seals in the injectors themselves failed and would keep the Cylinder fed with fuel and the engine would SCREAM itself to death!!

243 · #5 09-30-2002, 12:00 AM

It is possible to run motor oil thinned with gasoline but there are other fuels that would work much better and not damage your pump...like 1K or 2K Kerosene, Jet-A, Jet A-1, JP-5, and JP-8.

Silly question, if you have motor oil and gasoline, couldn't you just call for a ride, tow or find some diesel [img]smile.gif[/img]

www.turbodieselregister.com

[ September 30, 2002, 06:07 AM: Message edited by: 243 ]

Rogue · #6 09-30-2002, 05:35 AM

well...since motor oil and gasoline both have lower flash points than diesel...i dont know but ive been told...

Stolen76 · #7 09-30-2002, 12:46 PM

sure it would work, unless you had a weak piston, or an injector nozzle spraying off center. then it would only work until you burned a hole in the piston.

on the other hand, if you had an electronic injection engine... tips are finer and pressures into the 10's of thousands on some... you will blow the tips off the injectors and if you are lucky, it will shoot out the exhaust valve on the next stroke. been there, done that. A local fleet shop kept bringing in trucks with bad injectors on newer engines. found out their mechanic was filling the fuel filters with engine oil because it was easier to get to.

Careful34 · #8 09-30-2002, 02:48 PM

Thanks the replys guys! A few clarifications would be appriciated:

Roguestar: according to howstuffworks.com lubrcating oils have a higher vaporization temperature than diesel, so why is the flash point lower?

Stolen76: You're saying the engine oil would have a higher BTU content per gallon than the diesel, and so the diesel engine couldn't take the pressure when a amount of oil equal to the amount of diesel is injected? I understand! So if you were able to inject a smaller amount of oil it still might work? Is this what the fuel density compensator on a military multi-fuel engine does? Also: as the gasoline as a lower BTU/gallon value than diesel does, wouldn't you be able to theoreticly find amounts of the two to mix to average out to the same as diesel? I understand that straight oil would be too powerful.

Rogue · #9 10-01-2002, 03:47 AM

i shouldnt have used the word flashpoints and was thinking in terms of octane(gasoline engine), now that i removed my head from you know where, diesel engines use cetane ratings. the difference between octane/cetane and gas/diesel is way beyond me to explain. as far as the original question goes i'd say yea you could but i wouldn't unless i absolutley had to

Gladi8r · #10 10-01-2002, 10:21 AM

Why not just stop at Mickey D's and get some cooking oil??

http://www.journeytoforever.org/biodiesel_make.html

Stolen76 · #11 10-01-2002, 11:44 AM

Straight oil has a higher BTU, but it's more of a viscosity issue in the newer electronic engines. We commonly instal 2 micron filters, which oil can be pushed through. The problem is when the thick oil is in the injector itself it has a hard time making it through the tip of the nozzle at the velocity the plunger is forcing it through at. Sometimes it's just too much restriction and it pushes the tip off of the injector.

Careful34 · #12 10-01-2002, 02:06 PM

Stolen, That's sort of what I was thinking, wouldn't the gasoline thin out the oil to the viscosity of diesel if mixed in the proper proportions?

Glad, Tbat's not a bad idea! There are plenty of supermarkets and convience stores out there that sell cooking oil. I understand you can pour it right in!

andy d · #13 10-01-2002, 02:57 PM

uhhhmn, Careful doesnt cooking oil have to be heated 1st. like bunker oil does before you can use it to fire a boiler, Btw a buddy of mine has been heating his service station with waste oil heaters. these work by pre-heating the drain oil

Tiger Shark · #14 10-01-2002, 03:21 PM

andy you are right.. all of the "bio diesels" i have seen or read about start on diesel and have some sort of heater in the tank of cooking oil to warm it up before they use it. i got a ride in one of them that was on display a year or so ago at zoo-mass.

And on the subject of engines running away... had a 3-71 generator do this on a boat i was a deckhand on.

Talk about overheating.

I don't know too much about diesels but i think they stopped it by "throwing the rack."

Needless the say the gen set was trash after that one.

Careful34 · #15 10-02-2002, 03:07 PM

I'm not sure about the heating issue. I remember reading an artical in, I think, Mother Earth News were I thought they just dumped a bunch of cooking oil right out of the bottle into a test engines tank and it ran. I certainly could be wrong. I would think that would cast a shadow over bio-diesel too. Sort of a pita.

I have a chance to learn a lot more about diesels; I got a line on a free turbo diesel Jetta if I want it. Doesn't run of course, but that's how you learn; by fixing!

[ October 02, 2002, 09:08 PM: Message edited by: Careful34 ]

BigSHO · #16 12-17-2002, 08:42 AM

My wife is working on a project to make waste cooking oil into diesel fuel and you can mix it up in your back yard if you want to. All you do is get the waste grease and ad lye. OR you can get the reciept at
www.veggievan.or click on biodiesel and the green grease machine.
good luck
Carl

BigSHO · #17 12-17-2002, 08:43 AM

Sorry www.veggievan.org

Nobby · #18 12-17-2002, 11:14 AM

Yep you certainly can run a Diesel on straight cooking oil, you have to preheat the cooking oil The procedure as aforementioned is to start up on diesel warm everything up, you usually use the engine coolant to act as a preheating system for the cooking oil. When ready switch over to cooking oil and away you go. Shutdown is the reserve, ie switch over to Diesel and run for a few minutes.
Interestingly enough Rudolf Diesel envisioned his invention being run on Vegatable Oils and exhibited it running on Peanut Oil

tuckers89GW · #19 12-18-2002, 07:31 AM

here is a guy in Iowa that is running used veggie oil from Carlo's O kelleys.
FAT MOBILE
Pretty cool and easy to do.
I think it would make me hungry for french fries all the time.

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