Buyer Beware! 

According to some magnet vendors, magnets can be used to improve blood circulation, cure and prevent diseases, increase automobile mileage, improve plant growth, soften water, prevent tooth decay, and even increase the strength of concrete.

Most magnetic fuel treatment systems are marketed through independent distributors who sell out of their homes. An Internet search using the keywords magnetic treatment reveals dozens of independent distributor home pages. Very few such devices are offered by national chain stores or advertised in mail-order catalogs. Possibly, the magnetic-device manufacturers sell through independent distributors to insulate themselves from some of the more exotic claimed benefits of magnetic treatment, or perhaps consumer and wholesaler skepticism has kept magnetic treatment out of mainstream retail. Regardless of the reasons, magnetic fuel treatment devices are not usually available at the local hardware or automobile parts supply store. This lack of wide availability has given magnetic water and fuel treatment a sort of fringe-science status in the minds of many consumers.

Claimed Benefits and Effects
Prices for automotive fuel treatment magnets range from about $50 to $300. One or more magnets are clamped around or installed inside an automobile's engine fuel line between the gas tank and the carburetor or fuel injectors. Claims for these devices include decreased hazardous gas emissions, more complete combustion, improved engine power, longer-lasting engine components, and a 10 percent to 20 percent increase in gas mileage. The distributors of these devices rarely cite any documented test results which validate these claims. Instead, they rely on numerous testimonials, lists of corporations and municipalities that purportedly use the devices, and scientific-sounding explanations of magnetic fuel treatment.

Magnets and Magnetism
To many people, magnets are a complete mystery. Vendors of magnet-based scams often use this ignorance to their own advantage, so a familiarity with the basics of magnetism can aid in the detection of dubious claims.

Magnetic fields are produced by the motion of charged particles. For example, electrons flowing in a wire will produce a magnetic field surrounding the wire. The magnetic fields generated by moving electrons are used in many household appliances, automobiles, and industrial machines. One basic example is the electromagnet, which is constructed from many coils of wire wrapped around a central iron core. The magnetic field is present only when electrical current is passed through the wire coils.
Permanent magnets do not use an applied electrical current. Instead, the magnetic field of a permanent magnet results from the mutual alignment of the very small magnetic fields produced by each of the atoms in the magnet. These atomic-level magnetic fields result mostly from the spin and orbital movements of electrons. While many substances undergo alignment of the atomic-level fields in response to an applied magnetic field, only ferromagnetic materials retain the atomic-level alignment when the applied field is removed. Thus, all permanent magnets are composed of ferromagnetic materials. The most commonly used ferromagnetic elements are iron, cobalt, and nickel.

The strength of a magnet is given by its magnetic flux density, which is measured in units of gauss. The earth's magnetic field is on the order of 0.5 gauss (Marshall and Skitek 1987). Typical household refrigerator magnets have field strengths of about 1,000 gauss. According to the distributors, the magnets sold for fuel treatment have magnetic flux densities in the 2,000 to 4,000 gauss range, which is not unusually strong. Permanent magnets with flux densities in the 8,000 gauss range are readily available. The magnets sold for magnetic fuel and water treatment are nothing special; they are just ordinary magnets.

Automobile magnetic fuel treatment devices are either one or more magnets in a canister installed in the fuel line or a magnetic device clamped to the external surface of the fuel line. Magnetic treatment of fuel, it is claimed, results in increased horsepower, increased mileage, reduced hazardous gas emissions, and longer engine life.

Vendors claim that either mileage or horsepower will be improved by about 10 to 20 percent. They also claim that if no improvement in mileage is noted, then the improvement must have come in the form of more horsepower. This, of course, makes it difficult for a consumer to determine if his magnetic fuel treatment device works.

A literature search for magnetic fuel treatment studies revealed that such studies are practically nonexistent. Daly (1995) and McNeely (1994) are anecdotal accounts describing the use of a magnetic treatment device to kill microorganisms in diesel fuel - an application not usually mentioned by vendors. Tretyakov, et al (1985) describes tests conducted in which the electrical resistance and dielectric properties of a hydrocarbon fuel were found to change in response to an applied magnetic field. This report does not address whether the observed physical property changes might affect fuel performance in an engine, but it references two research reports that may contain performance data - Skripka, et al (1975) and Tretyakov, et al (1975). I could obtain neither report. Both are in Russian. My literature search search found no other credible research reports pertaining to magnetic fuel treatment.

The utter lack of published test data is revealing. According to the vendors, magnetic fuel treatment has been around for at least fifty years. If it actually worked as claimed, it seems it would by now be commonplace. It is not.

Vendors of magnetic fuel treatment sometimes respond to this reasoning with hints that the automobile manufacturers and big oil companies are conspiring to suppress magnetic fuel treatment to maintain demand for gasoline. Such a conspiracy seems quite improbable. This supposed conspiracy has not managed to suppress other fuel-saving innovations such as fuel injection and computerized control.

I found no test data that support the claims for improved engine performance made by vendors of magnetic fuel treatment devices. Until such data become available, considerable skepticism is justified. I believe none of the claimed benefits of magnetic fuel treatment are true.