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Chlorine in your engine

Chlorine Additives Can Cause Corrosion

Consumers frequently encounter “engine treatment” products containing chlorinated additives, often
demonstrated with oilless engines or bench tests such as bearing testers. Chlorine is used in this type of additive because chlorine reacts with the metal substrate to form a reactive species, or an oxide, which becomes a friction barrier and produces dramatic demonstrations on bench tests. However, the by-product of oxidated chlorine causes problems in both engines and the environment. Chlorine is
extremely reactive, making it corrosive to engine metals and interactive with many motor oil
components. And while these demonstrations attract attention, they do not represent “real world” engine operating conditions where chlorine’s long-term corrosive attack can outweigh any short-term benefits.

Quick reactivity

Chlorinated additives react quickly with metal surfaces due to high electron negativity. Therefore, chlorinated additives are sometimes used in industrial cutting fluids designed to meet the extreme pressure requirement of metal machining. Metal machining involves a “one pass” metal shearing operation in an open system with constant flushing, conditions not conducive to corrosive attack.

Hydrochloric acid corrosion

By contrast, the internal combustion engine involves a closed system with conditions described by Mr.
Maurice LePera, who served as Associate Director for Fuels and Lubricants at the U.S. Army’s Tank-
Automotive Research Development and Engineering Center, in the August, 1998, Lubes-n-Greases article “Chlorine & Engine Oils: A Good Mix?”:

“Chlorinated additives are not used in modern, fully formulated automotive engine oils. The environment within an internal combustion engine consists of high temperatures,combustion and blow-by gases, moisture, acid and oxidation precursors, wear debris, unburned fuel, etc. The combination of these ingredients when combined with the catalytic effects of metallic surfaces and trace soluble metals such as copper will cause the chlorine to hydrolyze, forming hydrochloric acid and other associated reaction products. Once generated, these acidic reaction products can cause serious internal engine corrosion problems, especially on ferrous and aluminum alloys.”

Specs prohibit chlorine

Certain chlorinated additive manufacturers claim that their products are non-corrosive. However, the
corrosion inhibitors are a short-term fix that leave engines prone to corrosion after the additives loose their effectiveness. Since the corrosion process is not visible to the vehicle operator, it can continue until the cumulative effects induce engine malfunctions and failures. Again, quoting Mr. LePera:

“Corrosion within an engine can be a ‘silent killer.’”

These concerns are supported by military lubricating oil specifications and commercial specifications
prohibiting use of chlorinated additives.

Engine components

Further, Mr. Cliff Gottlob of Gottlob Research and Engineering reports:

“This [by-product of chlorine in engines] is a very corrosive product that is not only detrimental to such components as bearings, pistons and any metal parts, but also the environment. ... The devastating effect of chlorine on such items as rubber, neoprene, cork and compositions which are basic ingredients used in seals, gaskets, etc., is extremely bad.”

Labels dodge issue

Unfortunately, many chlorine additive container labels do not state, “Contains chlorine.” Technically, chlorine in its pure form is a gas, so these products dodge the issue by using chlorinated hydrocarbons, paraffins, solvents, etc. If the additive container label states, “Contains no PTFE, graphite, molybdenum disulfide or solids,” the product may likely contain chlorinated additives.

Trick demonstrations

Due to chlorine’s quick reactivity, promotional demonstrations such as oilless engine operation and
bearing testers prove attractive to the unwary consumer. However, note comments from syndicated
newspaper column Drive It Forever by leading automotive expert Mr. Bob Sikorsky, member of the
SAE and STLE, nationally syndicated automotive columnist and author, and recognized consumer

“Sadly, a number of these [chlorinated additive] infomercials use trickery and deception to convince the public to buy the product. ... The demonstrations shown in these infomercials are meaningless, and have nothing to do with what actually happens inside an engine during operation. ... The downside, which of course is never mentioned, is that it’s extremely corrosive.
“Because they are so corrosive, the oil industry stopped using chlorine compounds as engine-oil additives more than 40 years ago. You, too, should reject any product that contains chlorinated hydrocarbons. ... I personally sent samples of both [Dura-Lube and Prolong] products to a respected lab for analysis of chlorine content. Dura-Lube tested at 6.8 percent chlorine, while Prolong came in, incredibly, at just under 30 percent. ... [From another column.] Motor-Up was shown to contain 17.9 percent chlorine.

“Choosing the right product could mean the difference between real 50,000-mile engine wear protection, and an engine hosting unproven possibly dangerous formulations. ...
Only ASTM- and SAE-approved engine tests are meaningful, and neither of these companies [Dura-Lube and Prolong] has proven its product under these industry-recognized testing procedures.”


An October, 1998, Consumer Report article, “Prolong additive: Don’t try this at home,” addressed the
infomercial demonstration issue:

“The bond is supposed to last even when the oil is drained. In the [Prolong] infomercial, Unser and others drive along a racetrack in the Mojave Desert without oil or oil drain plugs. The same ad, broadcast nationally, pictures a woman who, thanks to Prolong, supposedly drove from Santa Barbara to Los Angeles without oil. (The reason she stopped after 4 hours, 40 minutes, and 7 seconds? She was hungry.)
“We didn’t test the other claims, but we did see whether Prolong would protect an engine after the oil was drained.
“We installed a factory-rebuilt GM 4.3-liter V6 engine into each of two Chevrolet Caprices. We broke them in with Pennzoil motor oil, and added Prolong to one of them. Prolong claims to work immediately. We drove more than 100 miles, then drained the oil and started driving again. After only 13 minutes and five miles, both engines failed simultaneously.”

The QMI difference

By contrast, QMI Engine Treatment is a friction surface treatment with PTFE, which is chemically inert and therefore friendly to all engine components. QMI Engine Treatment was tested by Southwest Research Institute utilizing ASTM’s Sequence IIIE, producing 88% average wear reduction in a V6 Buick engine and passing the full battery of engine safety tests.
QMI has also proven effective in the demanding industrial market, which typically forbids the use of
chlorinated additives in closed lubrication systems.

(Other products known to contain chlorine: Energy Release, MT-10, Metal Lube, Militec-1, Motor up, Skorpion, IXL.)