a couple years ago i started saving up waste motor oil with the intent of building a waste oil furnace for the workshop, but that project is still waiting for to to build the rest of the walls on the workshop.
so as i stand right now, i have 3, 55 gallon drums full of WMO, including small quantities of gasoline, ATF, gear oil, and possibly small quantities of other automotive fluids.
i've read quite a bit around here about burning various oils as fuel, and personally have tossed in a quart of ATF with every fuel filter change, and thats about it. tonight i walked out to the workshop, pulled a gallon of oil from the middle of a barrel, ran it through a 100 micron paint filter, and poured it into the truck. its an 87 E350 with a 6.9.
as it stands right now, i have one gallon of WMO added to about 21 gallons of diesel in my rear tank, and plan to drive it tomorrow and see what i think. from what i've read here, people have consistent good results from up to 50% concentration, but i see no need to push it. i run 40,000 miles a year, so even with just a 10% mix i should consume my oil supply at a quite acceptable rate

i plan to start carrying a spare fuel filter at all times, and up to this point have been changing it about every 3 months, without being too precise about it.

are there any other concerns i need to consider for running such a low concentration of WMO?

 

You know I say go for it

I only ran WMO once, about a 50/50 mix (15w-40) with diesel and at that ratio my truck was dogged down, didn't want to accelerate, could barely reach 60mph, but other than that ran as normal.

I just dont want to run it cause I'm not really saving as much compared to running WVO. With WVO I can run as high as 90% WVO and still easy starting in morning. And on WVO my truck makes more power than diesel, is quiet, doesn't shake as much, etc. On WVO my truck actually accelerates up steep hills with a load no problem!

I have read that many use a 85%/15% WMO/gas ratio, but I have not put that much gas in my truck so don't know...

With a turbo you might not notice that "lag" as much as my NA IDI...

Also, I have read in various places that you should NOT add Diesel Kleen or any other additives when running WMO as the additives seem to react with the WMO and cause problems, separation, globbing, etc.

I only ran about 6 gallons of WMO with about 6 gallons of diesel, didn't notice any filter clogging, etc.

They also "say" adding gas to WMO helps to drop out metal shavings, etc...metal shavings would/should be the only real concern.

 

I've run W80 (80% centrifuged WMO, 20% regular unleaded gasoline) in my '83 Mercedes 300SD, but it smokes like crazy. Power seems about the same, engine seems to run hotter than normal (makes sense, since WMO has more BTU/gallon than diesel fuel).

The thinking recently seems to be that although regular unleaded gasoline is a great thinner, it has about zero lubricity and may cause issues with your injection pump and/or injectors. I'm not sure if that's really true on older, indirect-injected engines, since sometimes those manufacturers would actually advise you to use up to 20% RUG in the wintertime to avoid gelling of diesel fuel, but who knows.

I'd recommend you filter your oil better. 100 microns is definitely insufficient to avoid problems with your injection pump and injectors. You want to get it down to 5 microns tops, and preferably sub-micron (with a centrifuge). Also, you really want to get all the water out.

 

FILTER, FILTER, FILTER!!!!! aim for 10-20 microns. dont try to filter it all at once, work your way down to a smaller number. I have a 16 on my garage pump and a 10 on the truck.

From the sounds of it your oil is sitting still in a barrel, thats good, Best thing to do is let it sit in a hot building or the sun directly and let it gravity settle as long as possible, 1 week or more. Suck the good oil off the top and push it through a water trap fuel filter. I prefer the Golden Rod clear housing with replacable filters just so I can see whats in the filter. People say the water trap ones are a waste but more then once I have gotten a bit of water I didnt realize was in the oil and the filter stopped flowing, so it did its job, I think they're cheap insurance.

The bad thing with WMO is the high carbon count, carbon doesn't burn, it's SUPER hard and will score almost anything it goes through. if it's diesel oil there is ALOT of carbon in it, the blacker the oil, the more carbon. if it's gas oil it's got lots of corrosive stuff in it, that's why gassers use a PCV, they develop lots of weird toxins the cranckcase, which gets into the oil.

at the rate your using it I don't think you will have any problems immediatly but I would be cautious. I have not experimented with centrifugeing WMO yet, I have everything just haven't tried it yet to see just how much carbon it will sling out I think if you got the carbon out it would burn alot better.

Diesel Rod

 

my oil is indeed sitting quite still. the barrel i pulled from hasn't been moved in a couple weeks, my other 2 barrels for several months. on the current barrel, about a month ago i ran the pump from the bottom of the barrel until all the coolant/water was gone and i hit oil, then i let it sit for awhile. as mentioned above, when i pulled from it, i was pulling from about halfway up.
dieselrod, i look forward to hearing your results from centrifuging WMO, both from gas and diesel applications. my stock is primarily gas engine oil, with some ATF, diesel oil, gear oil, and possibly small amounts of whatever else i have around (brake fluid, solvent, etc), as until recently, all waste fluids went to the same place.

having run my current mix of 1 gallon in a full 22 gallon tank today, i'm pretty happy. there was a slight smell of burnt oil i could notice with the windows open, but really not much. otherwise, i think i may have noticed a slight power increase, but that may have been caused by a miscalibration of my butt-dyno, as those instruments aren't terribly accurate

i'll look into better filtration systems, i just figured the paint filter i had handy would pull out any sand or other big problems. reading around here, i saw a number of people filtering the oil through a pant leg, does anybody know an approximate micron level that gives you?

 

fueling up tonight, i found that if i neglect the WMO from my numbers, the fuel consumption appears to have not changed. i'm not sure if this is a difference in how full the tank got tonight, or if the truck is less efficient on this mix, but after i got home i added 1.5 gallons of WMO to go with the 16 gallons of diesel i had just pumped into the rear tank. i plan to check economy on a 5 tank test-run to see if it really saves me money, and go from there

 

I have done a fair amount of centrifuging waste oil. I have an IBC in the back yard into which I dump all my waste oil (engine oil, ATF, hydraulic fluid) and let settle for a while, then I pump off the top into a centrifuge barrel.

I've done 12-15 passes on this oil (which is black as midnight) after heating to 195 F, and while the centrifuge does pull some crap out, it doesn't change the color of the oil at all. Even after mixing the finished product 50/50 with No. 2 diesel, I can't see anything through it, even with a really bright light.

The centrifuge seems to be doing what it's supposed to, but I can confirm what lots of other people have said: a pressure-operated centrifuge (mine is a PA Biodiesel 120 GPH model) does not get the carbon out of used motor oil. Maybe a direct-driven, higher-RPM centrifuge would do a better job; I don't know.

I can tell you something interesting I discovered, though. Lots of people on alternative fuels forums will tell you not to thin oil with diesel fuel, because according to them diesel fuel is not a solvent. They say you need to use kerosene or gasoline.

Well, it's not true. I took a sample of my centrifuged oil and mixed it 50/50 with No.2 diesel in a clear glass jar and let it sit for a week. There's no separation whatsoever. I also took another clear jar and put some virgin ATF and virgin 5W-20, and mixed those 50/50 with No. 2 diesel, let it sit for a week. Same result; no separation. Also, mixing 50/50 with No. 2 diesel noticeably reduced the viscosity of the oil. So I would conclude that you can use diesel fuel as a thinner without worry. It's not the cheapest solution, but it works well.

 

I read somewhere there is a way to make wmo translucent but can't find it now..

here's some good info
Waste Motor/Hydraulic Oils & Blends

here it is...mmm that stuff looks good
http://www.microcogen.info/index.php?topic=2633.0

 

That stuff is produced by a guy named Jeffrey Brooks, of Beyond Biodiesel. I agree that his results sound very promising, but his equipment is specialized and I don't believe I've ever seen anyone else reproduce his results.

In any case, by Jeffrey's own admission this is a very labor-intensive process (more labor than I feel like doing, anyway), and as others have pointed out, we have no assurance that various additives and contaminants have been removed. Just because you can see light through it doesn't necessarily mean it's good for your injectors.

 

I agree.
The problem is that WVO is not so readily available anymore as it's a commodity now and many corporations are involved in it. So, the small guys like us who just want it for personal use are being shut-out.

WMO is very available but is far less desirable in many ways to WVO.

I think soon enough WVO will be almost impossible to get, stricter emissions will also probably soon be enforced to try and eliminate all older vehicles too.

It sucks, best fuel in the world (best because it's a waste product and more green-friendly) and the common man can't get no WVO...

There must be a simple way to process WMO (that is 100% pure WMO, no contaminates) so that it will mix easily with diesel, etc and get rid of any bad side-effects...we just haven't found it yet...

 

Tell me about it. Around here it can't be found, even offering to pay market rate (and educating local businesses on the fact that I'm local myself, not some huge out-of-state waste hauler that couldn't care less about keeping the money in our economy). And unlike some people I've read about in the news, I'm not willing to steal it, though it would certainly be easy enough to do so. It seems if you're honest and want to conduct business in a straightforward manner, you're putting yourself at a disadvantage.

Yep. I have had no problem getting people on Craigslist to give me literally more WMO than I know what to do with, but the quality varies widely. Some of it is fantastic (nearly new hydraulic oil from a local power gate company), while some of it is terrible (barrels left out open in the rain, antifreeze mixed in, things like latex paint mixed in, etc). WMO smells terrible, is carcinogenic, makes a huge mess ...

I hope out here in the Wild West, that's not true, though I do worry about moving to a bigger city that would require me to do annual emissions tests. These old 1980s cars are great except for that aspect.

Well, my experiments have proven to me that WMO will mix readily with pump diesel no matter how contaminated it seems to be. But as far as getting rid of contaminants, I'm not convinced there's any way to do that short of owning a recyling facility.

 

no doubt
my truck runs on it, and i got like 60 gallons from a guy with a Stroke F350, and it was 15w-40, and looked pretty clean, no other stuff, etc.

but, my truck ran like a slug, and pedal almost to the floor just to do 65mph.

probably should've been using a thinner oil but it's not nearly as cost-effective as wvo since you have to have at least a 50/50 ratio with diesel.

some say 85/15 diesel/gas but I just don't know if that high a percentage of gas is good, especially in summer heat...IDK...and generally any gas or alcohol is a no-no

OH BTW I used a pair of jeans, turn one leg inside-out, wrap ends of both legs with zip-ties, put inside-out leg into other leg (double-filter) and put a long funnel in leg, fill with 4-5gallons of oil and in about an hour you'll have filtered oil.
time would be less if oil is heated first or mixed with diesel/kero/gas
I heard jeans, especially doubled-up, are about 5-10 microns....

gas, acetone, alcohol all seem to help drop bad stuff out of the wmo, if only there were a simple way to recover the gas, etc.
alcohol would probably be the easiest to recover back out of the oil or no? cheap too.

and, I guess if you're gonna go the 85/15 route with gas, maybe just mix it in, let it settle, then filter it all from top and disregard stuff near bottom of barrel, etc

 

Oh. I meant to say that I would avoid brake fluid at all costs. It's corrosive and I imagine could do a real number on the insides of your injection pump, not to mention your cylinders and valves.

 

thats good to know about the evils of brake fluid... i suspect some is mixed into my drum. but i believe it attracts itself to water, so hopefully its hanging out with the water at the bottom of the drum, is that likely, or is that just way too scary to gamble with??

 

Hygroscopic?

I think brake fluid, PS fluid, Ethanol, are all Hygroscopic or attract water

from Wikipedia seems like everything attracts water