The first indication of major engine trouble, all too often, is either an alarming noise coming from under the hood or a breakdown.
But with some preventive maintenance, it is possible to know your engine's condition before a major malfunction. A variety of diagnostic tests can provide a detailed and accurate assessment of an engine.
One of the most useful tests includes engine oil analysis, which is widely used by major automobile, truck and airline fleets to track the condition of equipment.
By chemically analyzing engine oil, it is possible to determine not only if an engine is wearing out at an accelerated rate but also which parts may be in the worst shape.
As engines age, they shed minute amounts of metal that are carried away in the oil. The analysis identifies and measures these metals. The analysis also can tell a motorist whether the fuel system, cooling system and various filters are operating properly.
These tests are so accurate that they can determine the oil brand and the oil viscosity.
Major oil companies, such as Texaco and Mobil, have the oil in their fleet cars analyzed every two months in hopes of avoiding costly repairs down the road.
Until recently, engine oil analysis was available to fleet operators only. Now, one of the nation's largest oil analysis laboratories is targeting consumers.
Spectro Metrics Inc. of Atlanta offers a kit for extracting oil and mailing in the sample. It then returns a complete diagnostic report on your engine. The service is marketed through a second company, Detect Auto Labs.
A motorist extracts the oil sample from the dipstick hole with a special syringe and puts it in a plastic vial. The car model, odometer reading and vehicle identification number are recorded on an information sheet that is sent in with the sample.
The Spectro Metrics analysis is done by an automated spectrometer, an instrument that can determine the chemical makeup of an oil sample. The lab's database contains information on the metallurgical makeup of every engine on the market. The lab determines if the metal composition in the oil is out of a normal range.
If excessive chrome is found, for example, it is presumed to be the result of ring wear. Excessive nickel indicates a valve-wear problem. Too much dirt usually points to a bad air filter or oil filter.
Other tests check for excessive fuel dilution of the oil and seepage of radiator coolant into the oil. About 8% of cars tested have fuel dilution; 5% have coolant leaks. As little as 1 part per million of coolant can be detected--the equivalent of a shot glass of water in a swimming pool.
The lab report includes a paragraph of diagnostic information as well as a chart detailing the findings in 20 specific categories of contaminants. It does not provide information on what it considers a normal amount of contaminants, because the company regards that as part of its proprietary database. But the diagnosis will highlight readings that are not normal.
The service costs $16 if ordered directly from Spectro Metrics. The kits are also marketed by Detect Auto Labs in some auto-parts stores at different prices. To order a kit, call (800) 336-9365.