Diesel Fuel additive research results

[NJT 5573]

Seems reasonable to use 2 stroke motor oil as a fuel additive for a 2 stroke engine!

What a stroke of genius, those numbers are pretty good and the price is right in there too.

Red Dog, When I was a kid, for 10 years, I pulled produce from Ca/Az to Calgary and Winnepeg and meat back to So Cal. If I got caught comming or going with #2 in the tank in the cold, (real cold), I used to mix a couple gallons of gas to the #2 to keep me going until I got a tank of #1. That came from my shop foreman and I was part of a 150 truck fleet. Those trucks had one fuel tank mounted behind the sleeper out of the airstream.

I had a 4 stroke Cummins in those days and don't think I would ever do this to my bus engine.

[Reddog]

I used to run Schaeffer synthetic two stroke oil as a fuel additive in my '81 Wanderlodge, seemed to work fine, but it seemed to run fine without it as well. I would sure go with a 2 stroke oil as opposed to ATF just because i don't know what all additives they put in ATF, I know it has some seal softeners that I don't think I want sitting in my injector pump.
  I've had some locals talk about the gasoline in the diesel trick for cold weather, but like you say, they uses it as a last resort when they can't get any #1.
Doug Engel, Gunnsion, CO (-26 this AM)

[lyndon]

When it got so cold that even winter fuel started to gel, we used to carry a gallon or two of kerosene to thin the fuel. I would hesitate to use gasoline for its lack of lubricity.

Don

[white-eagle]

Jack, thanks for the post in the first place.  all the rest of you, or at least a lot of you, thanks for making me feel not so bad for not knowing what's right.

i have put up to half tank of 2 or 3% biodiesel into my tank and it seemed to run better.  i THINK i got better mileage and maybe better HP, but i only knew of one place to buy it, so when the tank's empty, we buy flying j. 

seems to me the specs indicated that bio was the best lubricity "additive".  why not just run bio diesel? or at least the premixed stuff i found at the local farmer owned place?

[Chris 85 RTS]

I've debated this study on other sites before, and I am in line with what Christy said, which is they add the additives and compare the results to fuel we can not even buy. 

"The independent research firm obtained a quantity of "untreated" ULSD fuel
from a supplier. This fuel was basic ULSD fuel intended for use in diesel
engines. However, this sample was acquired PRIOR to any attempt to
additize the fuel for the purpose of replacing lost lubricity. "

What we really need to know is what is average of the fuel we can buy.  Then using a representative, or even worst case sample of that, what do we need to add to make it acceptable, if anything.

I'd also like to point out, that many of the failure reports I have read about have been on newer trucks, not older DD's.  I believe these newer injector pumps are much much closer in tolerences than anything we had on our DD's.

[HB of CJ]

Chris has it right.  My '82 VW Rabbit Diesel has a wopping 5,000 psi injection pressure.  The new Detroits have, if I read it correctly, way over 30,000 psi injection pressure.  Quite a difference.  The operator's manual with my VW Rabbit says I can add 10% gasoline to #2 Diesel to thin out the fuel for emergency use in the winter.  My Rabbits' injection pump is basically Bosch-type late 1930's technology and the entire vehicle is basically your low-tech (now) cheapo production stuff.

I would hate even to think what a new injection pump with injectors will cost to exchange out on one of the new 2010 type emissions heavy truck diesels.  $Name your own manufacture$.  Just a new pump may cost more than my entire 1974 Crown Super Coach is worth!  Figuring out the entire $stake$ with all the new equipment on the road boggles my feeble mind.  What we Bus Conversion People may need to do is find an additive that WORKS and is $cheap$ to use. 

[junkman42]

The common rail injection systems generate all of the high pressures within the injector itself.  Fuel at about 80 lbs and oil at pressures lower than common tractor hydraulic pressure is used to operate a multiplier piston and are electro mechanicaly actuated and in some pizeo electric tripped.  The only lube problem they have is in the piston bores.  Most all are rated for dry fuel meaning jet fuel.  Makes one wonder about lubricity.  My two cents worth.  John

[lyndon]

This topic got me flipping through my MC-9 Maintenance Manual (1-1-89; Section 9, Fuel System) and I found some interesting -- some surprising -- statements:

About heating fuel (kerosene?):

"The ignition quality (cetane rating) of burner fuel (ASTM D-396) is poor compared to diesel fuels (ASTM D-975)."

Lube oil:

"TMC/MCI does not recommend the use of drained lubricating oil in diesel fuel. Furthermore, Detroit Diesel Allison will not be responsible for any detrimental effects which it determines resulted from this practice."

Alcohol:

"Very small amounts of isopropyl alcohol (isopropanol) may be used to preclude fuel line freeze-up in winter months. No more than one pint of isopropyl alcohol should be added to 125 gallons of diesel fuel for adequate protection."

"CAUTION: Commercially marketed diesohol or gasohol or gasoline should never be added to diesel fuel. An explosion and fire hazard exists if these blends are mixed and/or burned."

(Nothing said about engine damage, though.)

Fuel Additives:

"TMC/MCI does not recommend or support the use of any supplementary fuel additives. These include all products marketed as fuel conditioners. smoke suppressants, masking agents, deodorants, and tune-up compounds."

They continue with a DD warranty disclaimer.

Sulfur:

"The sulfur content of the fuel should be as low as possible to avoid premature wear, excessive deposit formation, and minimize the sulfur dioxide exhausted into the atmosphere."... and, ... "Too high a sulfur content results in excessive cylinder wear. For most satisfactory engine life, fuels containing less than 0.5% sulfur should be used."

That one surprised me. Isn't replacing the "lubricity" of sulfur in modern ultra-low sulfur fuel the whole reason we are discussing using additives?

Don

[Sean]

...

That one surprised me. Isn't replacing the "lubricity" of sulfur in modern ultra-low sulfur fuel the whole reason we are discussing using additives?

Don,

The sulfur itself is not where the lubricity that is lost comes from.  It is the process by which the sulfur is removed, which also reduces total aromatics, that is the problem.  Sulfur is not a lubricant -- the aromatics are.

-Sean
http://ourodysssey.blogspot.com

[lyndon]

Thanks for clarifying, Sean. After what I've been hearing about ULSD and lost lubricity, this had me scratching my head.

Don

[makemineatwostroke]

lyndon, the 0.5 low sulfur fuel was 5000 PPM ( A spec they have had for years) and the new fuel is at 500 PPM down to 15 PPM and only time will tell. I don't think the low sulfur fuel will have any effect on the 2 strokes because when EPA dropped it to 1500 PPM in the 90s DD did not send out any service bulletins about the fuel   But I do think it will probably have some effect on injection pump type engines if they are not design for the new fuel