The Science of it All Part II
by JIM STUART
Engine oil additives
Do they really work?
That question has sparked controversy for years in the automotive and diesel industries. Are the various engine oil additives really just the modern automotive versions of ��Snake Oil��? Many engine oil additives promise to reduce friction. The presence of friction �C metal on metal inside the engine��s combustion chamber - generates intense heat and often indicates the galling of metal parts and surfaces. In other words, your engine is being gouged, scored or gashed piece by piece over time. (See test photos at reference below).
There are several major kinds of engine oil additives:
1.Ptfe engine oil additives (Polytetrafluoroethylene, which is Teflon TM).
2.Engine oil additives containing solvents and detergents, such as kerosene, naphthalene, xylene, acetone or isopropanol.
3.Engine oil additives containing zinc dialkyldithiophosphate (��zinc�� for our purposes here).
4.Engine oil products using the same additives used by oil manufacturers, only in different amounts and combinations.
5.Other engine oil additives such as chlorinated paraffins and molybdenum.
Ptfe
Polytetrafluoroethylene got off to a rough start in its early career as an engine oil additive. The DuPont Chemical Corporation, its inventor, issued a now famous statement which read: ��Teflon is not useful as an ingredient in oil additives or oils used for internal combustion engines.��
By court action, DuPont was forced to sell Ptfe to manufacturers of engine oil additives. To their credit, DuPont still maintains they have ��no knowledge of any advantage gained through the use of PTFE in engine oil.��
Why the controversy? Remember, this additive is a suspended solid. Imagine introducing an additive with solids which your oil filter is designed to remove. So, your oil filter collects as much of the suspended solids as possible. The result? Clogged oil filters and a marked drop in oil pressure.
Ah, but there��s a ��comeback�� to that critique. Manufacturers claim it is of sub-micron size, passing through engine oil filters.
That isn��t the whole story.
I��ve spent nearly three decades working to find chemical solutions to industrial problems. When you test chemicals, you must follow them through the whole cycle of their use.
Polytetrafluoroethylene expands radically in size when subjected to heat. It starts out ��sub-micron��, but you won��t find any guarantees that it will stay that size when engine heats to normal operating temperatures.
Ptfe is often criticized for the oil pressure drop accompanying its use. This again is probably due to the clogging of oil filters. What is disturbing is that there are tests showing the presence of iron contamination in the oil due to increased engine wear after its use.
Maybe this one is best kept in your non-stick frying pan.
Solvent and detergent engine oil additives: Outmoded?
Engine oil additives designed to dissolve sludge and carbon deposits inside your engine use solvents and detergents. They are usually naphthalene, xylene, acetone, isopropanol or kerosene in a standard mineral base.
The problem? They can strip away more than sludge or deposits. They can strip away the boundary lubrication layer provided by your motor oil. With that, you would be promoting increased metal-to-metal contact within your engine.
��Miracle�� Zinc?
Zinc dialkyldithiophosphate (��zinc��) was originally touted as the ��miracle�� engine oil additive, replacing Ptfe. As an engine oil additive it has been used in many standard additive packages.
Zinc is advertised for extreme pressure, anti-wear engine protection. It is particularly useful in high stress, prolonged metal-to-metal conditions found in racing. But, for all of its fanfare, racing conditions are not what the vast majority of motorists face.
Your automobile should never face such stresses under normal, everyday driving conditions. Interestingly enough, years ago oil companies reduced the amount of zinc in standard engine oil packages because of damage to catalytic converters and increased spark plug fouling.
Furthermore, zinc is a hazardous substance. It has the capacity to inflict serious damage to your eyes. As an engine oil additive, it really hasn��t ��lived up�� to its original high expectations. And as a ��miracle��, you won��t start a new religion with this one.
Same additives used by car manufacturers
The oils from major oil companies servicing the automotive, truck and bike industries already come ��loaded�� with engine oil additives and work in combinations, synergistically. Adding more of the same additive will not bring added benefit.
Many things in the world of chemistry act in such a way that more is definitely not better. Think of adding a hot pepper sauce to a mix. Some adds flavor. More can make for a memorable event.
Sulfur compounds, for example, are used to protect your engine at lower engine temperatures but coke out forming sludge at higher temperatures. More will not help your engine and can, in fact, do actual harm.
