Lubrication additives for Diesel Fuel in older tractor

   / Lubrication additives for Diesel Fuel in older tractor #61  
It is my understanding that soybean oil added (biodiesel) is far superior to other options in added lubricity. Your state may be adding bean oil to your diesel. It can be a seasonal additive. Here in MN, they add quite a bit (20%) in summer-delivered fuel, and very little (5%) in winter fuel. In my opinion, this additive is already adding plenty of protective lubricity. I try to keep a blend in my diesel can, of 5% winter and 20% summer. You may want to research my advice. Years ago I'd add lubricity, but in the last 15 years I don't bother since this mandated biodiesel thing.
“In March 2002, the Minnesota State Legislature passed a bill which mandated that all diesel sold in the state must contain at least 2% biodiesel. The requirement took effect on June 30, 2005, and was the first biodiesel mandate in the US.”

   / Lubrication additives for Diesel Fuel in older tractor #62  
These are the results of comparing various lubricating additives that I found a while ago and believe are correct.


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   / Lubrication additives for Diesel Fuel in older tractor #63  
I use Howse Fuel Treatment & Marvel Mystery Oil (for lubricity); and Kill-Em to prevent biological growth in stored fuel. While none of that may be necessary; I use it for peace-of-mind. As others have observed, careful maintenance & care are cheaper than major repairs.
   / Lubrication additives for Diesel Fuel in older tractor #64  
Would a stabiliser product like Stabil do the job? I use this product on diesel for out of road machinery, like winterized stove oil when it is not frequently used.
   / Lubrication additives for Diesel Fuel in older tractor #65  
Let's clear a couple things up.

First; Yes, old truckers (I am one, retired, as was my father) added ATF to their old diesel fuel, many times the fuel was questionable and oil helped, it was basically hydraulic fluid back then. The injection systems were "loose" and you could run almost anything that would burn through them.
Time changes things. Modern ATF is far different, it now has friction modifiers and other additives, it isn't meant to burn, and you really don't want it in a modern fuel injection system with very it's tight tolerances, you will get more wear, plus deposits in the combustion chamber.
One other concern is gov't fuel checks. If fuel appears red, you will have problems.
Yes, I know some are using it and "haven't had any problems," YET! You're playing russian roulette with your motor.

Marvel Mystery Oil is a solvent, not a lubricant, read the label. Yes, it will help keep your fuel system clean, but not lubricate it.

I have always used Power Service, winter or summer blend, or Howes, in all my diesels, and added a couple ounces of 30wt NON-DETERGENT motor oil or NON-SYNTHETIC 2 stroke oil, to my older diesels. You don't need much, I use an old quart container, tip a little oil in, just enough to cover the bottom, then fill with PS. In my tractor I tip a couple ounces of the mix in (shake well) before fueling so that it mixes thoroughly. In a larger fuel tank I put more in. You don't have to do it every time, every other is good enough.
Other additives designed for diesel are also OK, just don't get anything with alcohol.

Red dye is added at the loading rack to the diesel fuel as it is being loaded into the tankers, I hauled it and witnessed it myself. It is exactly the same fuel as undyed. It is just not taxed.

Really the biggest problem with fuel today is moisture, it will destroy a diesel. It doesn't always come from your supplier. the temperature changes can cause condensation in your fuel tank.

Happy trails and long diesel life to everyone.
   / Lubrication additives for Diesel Fuel in older tractor #67  
Few things I’ve learned from running all classes of Diesels over the last 50 or so years. Also, adding oils to the fuel applies to pre-regen/cat type Diesels only, if yours has a regen converter on it, I advise you to stick with the over the counter lubricity products from Amsoil or Stanadyne, regen systems aren’t cheap to replace.

Before we get to the list, the biggest cause of Diesel secondary fuel system wear/problems is water and contaminants in the fuel. Keep your filters changed and drain your separators. No amount of lubricants will make up for having trash in your fuel, water is both a solvent and abrasive in a secondary Diesel fuel system. (Water is the universal solvent on the planet and given sufficient pressure, flow and time, it will cut through almost anything) When you pick a water additive, if your fuel system has a water trap ALWAYS choose a water dispersal product, NOT a water emulsifier. You need to remove the water, not break it up so it flows through the high pressure stage. If your fuel system doesn’t have a separator, get one.

Here goes:

1) Used engine oil, don’t do it, it only introduces metallic particles, unburnt fuel, water condensate and acids into your fuel system. None of these are good in any quantity.
1B) New engine oil, not good either. It’s not designed to be combustible so it will initially leave tar like deposits in the combustion chamber and exhaust ports that eventually harden and potentially cause port blockage or combustion chamber interference.
2) Marvel Mystery Oil. I don’t recommend this for lubrication, it’s fine as a general fuel system additive for older gasoline engines with steel fuel system components that benefit from its cleaning and anti-corrosion properties but it will not act as a good lubricant additive in secondary high pressure diesel fuel systems. To its credit, it’s designed to combust so it shouldn’t add too much to carbon deposits in the chamber and exhaust.
2b) Same for ATF, it’s more of a cleaner/dispersant than a lubricant. It has friction modifiers for bands and clutches to enhance friction. Also keep in mind the majority of rotating components in an auto trans are suspended on roller bearings which require light weight oils with minimum boundary layer tendencies as they are designed to roll on each other, not slide on a boundary layer which would cause additional heat and breakdown of the fluid.
3) Outboard motor or other 2 stroke lubricants. These do provide “some” lubrication and anti-corrosion protection however their biggest benefit is combustion enhancement. The outboard motor tc-w type oils provide additives to enhance flame front propagation in the cold temps that outboards run at normally along with deposit reduction additives for cleaner combustion chambers and ports. For example, in the 12v Cummins with either the rotary or in line P pumps, Wally World Outboard mixed at 200-1 with Diesel will result in about a 1/2 MPG increase, improved off idle throttle response/spool up and driveability. (The 12Vs in my experience will also have slightly less soot out the pipe, idle smoother as well as sound louder at idle as the combustion is likely more consistent) Avoid any 2 stroke oils with a red dye, you never know how zealous the DMV guy will be if you get sticked on the road.
4) Over the counter Diesel additives. These are the go-to products for all Diesel’s. They are tested to provide the maximum efficiency, anti-gel and wear protection at the ratios specified on the labels.

My recommendation is to pick a fuel additive product, mix it as directed and stick with it. Choose one brand/product and stick with it, you don’t know how they may react with each other. These companies hire engineers to determine the best way to use their products, although I hate to admit it, they know more than I do. My 2 favorite products are in order Amsoil “all-in-one” and if I’m on the road and need a substitute, Stanadyne.

A short note about “extreme pressure” additives. These are primarily used in applications where pressure fed lubricant systems aren’t present (or practical) to provide a refresh of boundary layer film and the assembly has one member that slides against the other member under high load at relatively low speed/short duration. Examples of this are hypoid differential ring and pinion teeth, flat tappet cams/lifters. The additives used in these applications are mainly metallics such as zinc, molybdenum and sulfur. These additives are attracted to the components and when under high load basically slide on the surfaces, forming a microscopic “wedge” of material between the members thus reducing, but not totally eliminating metal to metal contact. These are not without problems however, for example sulfur attacks “yellow metals” such as copper & brass, this is why most electric fuel gages in old Diesel equipment doesn’t work, the fuel eats away at the sender components in the tank or Harley Sportster riders that put EP90 in place of “Sportrans” fluid in ‘86 and later bikes that have alternators in the primary.
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   / Lubrication additives for Diesel Fuel in older tractor #68  
You can use Mystery oil.. 4 ounces to 10 gallons of fuel.. Same for atf or 2 stroke oil would be fine...
The flash point of marvel mystery oil is about the same as diesel, so it combusts evenly with the diesel.
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   / Lubrication additives for Diesel Fuel in older tractor #69  
These are the results of comparing various lubricating additives that I found a while ago and believe are correct.
I have been using the Opti-Lube additives in all my diesels, Opti-Lube has hightest tested lubricity results of any tested as far as I know. No smoke from my tractor or generators.
   / Lubrication additives for Diesel Fuel in older tractor #70  
given moisture is the main culprit of injector failure in the discussion, too little attn is given to supplier moisture contamination issues. just go high volume suppliers if possible.
operators with their own bulk storage systems are responsible for their own moisture related challenges. lots of info on that subject in this forum history. regards