Will a 250 Cummins run on waste oil? My observations over 3 years.

[sandcobra164]

Short answer, yes it will. Now onto some background. I used to have an M35A2 and a friend of mine still does. I put anything petroleum based in the fuel tank of that truck for years with no worries. Drained oil from the car, lawnmower, friends waste oil, good to go! My friend built a very impressive filtration stand. 10 micron water block filter to a 5 micron to a 2 micron into a centrifuge powered by a 10 gallon per minute pump. He gets waste ATF from a local shop and blends it 50/50 with pump diesel. I got my 5 ton around 3 years ago and only go by the shop when he has a good mess of fuel blended up to top off. I normally just put pump diesel in it. The truck runs fine on the blend. Over the past year, I haven't been to a diesel pump at all. My friend found a good source for diesel and ATF so aside from processing costs, free fuel. My truck likely got to 50/50 absolute and all seemed fine. Made the 190 mile trip each way to Durhamtown but couldn't help but think it was a little low on power. The deuce following me almost pushed on my tailgate going up some hills. It also smoked quite a bit and took quite a few more rotations of the starter to get going. I went to the gas station today. It took 30 gallons of diesel to fill the tank up so I'm likely at a 75/25 blend now. I drove the truck about 15 miles to get the exhaust cleared up on the new blend and guess what? I think the truck now has about 50 more horsepower. I like the idea of free fuel but I think I'm going 100% diesel from now on. I've read on here that 50/50 is fine and the 250 Cummins will be happy with it but I have to disagree. If you're going to do it, you will lose some power. Might not matter if you're not needing full power but when I go to Durhamtown, I run interstates, hills, etc on 14's. I can't drop below 55 mph to keep friends and blended 50/50, it won't do it. 55 mph comes around 1,750 rpm, let it drop below that on the blend and it can get as slow as 45 mph before it'd downshift to 4th. Now, it tows a 6,000 pound trailer stronger than it would run empty! Maybe a turbo would help the blend burn better, I'm sure it's compression related as the deuce has 22 to 1 versus about 17 to 1 for the Cummins.

 

[gimpyrobb]

No need for guessing, ATF has less BTUs than diesel. Why WOULDN'T it have less power?

 

[gimpyrobb]

I couldn't find the website I found the info at, but here is an interesting article. It even says new ULSD has all the lubrication the old diesel had!

http://www.trucktrend.com/how-to/transmission-drivetrain/0901dp-automatic-transmission-fluid-fuel/

 

[sandcobra164]

Gimp, Great article link. In other news, my friend who makes the blended fuel also gave away the 7, 12 packs of Miller Lite that he had saved for you! I'm not sure if that would have re-couped your fuel costs but you know what to expect when you make it there next year to the Ga get together of friends and trucks in October. I got one of the 12 packs but it's in my closet for emergency purposes like miscounted Saturday night and a race is on!

 

[gimpyrobb]

I got some fuel and beer from him last year, he is good people! Fuel runs great in my truck.

 

[73m819]

Your IP will not like anything other then diesel, the internal tolerances ARE a LOT tighter then a multifuel.

 

[Welder1]

I got some fuel and beer from him last year, he is good people! Fuel runs great in my truck.

Gimp,

I hope you can make next year I will take care of you then with beer and fuel again. We missed you this year and couldn’t even give the beer away. Your transportation guy who brought the parts declined it. I tried so ended up giving most to SandCobra’s national guard buddy who came with us. Thanks again and PM me your address in case I find something you might need.


Eddie

 

[dmetalmiki]

We ran a Cummins on our 'mix' but it was very much slower than already slow!. And it was fitted with a 6 speed gearbox.

 

[sandcobra164]

Truck started much easier today. We had a low of about 38 degrees overnight, I started it this afternoon while it was about 62 degrees out and it lit off on about the 4th rotation of the engine. Before, it would labor to start at this temp after sitting for a few days. It started as good as it did in the summer with sustained 90 to 100 degree temps.

 

[turbobill]

Over the years I've fooled with waste vegetable oil in my various diesels, from IDI naturally aspirated to DI turbocharged (Power Stroke). Even experimented with an 83% gasoline/17% WVO mix in a turbocharged Isuzu Trooper diesel (warm weather only). I've found that the thicker the mixture, the slower the starting. Never noticed a power loss so much but the WVO mixes did eventually clog (partially) the filter socks on the fuel pickups in the tanks. I eliminated those and installed see through filters just ahead of the primary fuel pumps. When they started clogging, I'd change them. Ultimately, I cut the percentages of the thicker liquids down and have no problems whatsoever, in either starting, running, or power.

While I've often thought about using WMO, my biggest concern was filtering the very fine suspended particles. As I now have an M923 with the 250 Cummins, I may revisit the issue next spring when it is put on the road.

 

[MAdams]

I ran 20% wmo and 80% diesel in my 8.3 and the injectors coked up quickly. The tips of the injectors had build up and it interfered with the spray pattern. EGT's were high and it would smoke at idle.

 

[snowtrac nome]

Tthe 2 things I worry about are particulate matter suspended in the oil, and viscosity most injection manufactures will caution you not to mix over 10 percent. I ran a 6 b cummins once on almost straight used motor oil and eventually had to replace an expensive bosch ve pump, my injection guy looked at the damage and told me the pump was damaged from too thick of viscosity. I have since refrained from adding too much oil since, yes the ulsd does have lubriticity agents added to it to preserve the moving parts in your fuel system

 

[sandcobra164]

A little more progress today. Took an M1082 trailer for a ride around the block. Truck would struggle to get to 45 mph with the 7,000 pounds in tow. It ran at 55 mph unhooked. Added a 32oz. grey bottle of power service, drained the fuel filter and let the truck idle for an hour. Took it almost the same route but extended the ride since it was running so good. I can now tow the load at 55 to 60 mph with throttle to spare once up to cruising speed. It revs about 200 rpm higher before up shifting as well. Once home, the truck had a nearly clear idle. It still has about 25% waste oil in the tank but I'm going to get back to 100% diesel in the coming months. My Deuce loved running on anything petrol based, I think the NHC-250 is a little more picky!