OIL ANALYSIS & INTERPRETATION

Oil Analysis is designed to evaluate the condition of your machine compartment, rather than just the oil condition. This microscopic view (right) shows metal and dirt particles filtered from oil samples. If these particles had gone undetected, total engine failure would have been imminent.

Wear Metals

Aluminum (Al):

Pistons, bearings, housing metal, thrust washers, converter and pump bushings, dirt entry (clay soil).

Copper (Cu):

Bearings, bushings, thrust washers, discs, cooler cores. Copper levels can vary widely and should be ignored unless accompanied by elevated readings for any other metal or in the presence of antifreeze. Copper is also used as an additive in some oil.

Chromium (Cr):

Chromed parts such as piston rings, bearings.

Iron (Fe):

Gears, shafts, cylinders, liners, valve train components, other steel components and rust.

Lead (Pb):

Overlay on main and rod bearings, turbocharger bearings, camshaft bearing and some bushings.

Molybdenum (Mo):

Piston rings, also a friction reducing agent in some oils.

Tin (Sn):

All roller or ball bearings and some engine bearings.

Nickel (Ni):

Found in certain wheel group bearings.

Contamination Metals

Silicon (Si):

Contamination from dust or dirt, anti-foam agent. Silicon is also found in greases, gaskets, and antifreeze.

Sodium (Na):

Antifreeze formulas, also an additive in some oils.

Potassium (K):

Found in extended or long life coolant, and many conventional coolants.

Additive Metals

Calcium (Ca):

Dispersant and detergent additive.

Barium (Ba):

Dispersant and detergent additive.

Magnesium (Mg):

Dispersant and detergent additive.

Phosphorus (P):

Anti-wear additive.

Zinc (Zn):

Additive packages of some oils, essential in high impact and high stress load areas.

Particle Count

The S•O•S lab uses a particle counter with a laser diode detector to actually count the number and the size of particles in your oil. Having this information is critical in helping the S•O•S Interpreters determine if excessive wear or dirt entry is occurring.

The lab measures particles greater than 5, 10, 15, 20, 25, 50, 75 and 100 microns in size in transmission and hydraulic systems. For geared compartments, the lab measures particles greater than 15, 20, 25, 50, 75, 100, 150, 200 microns in size.

Particle Counting is used in conjunction with Wear Metal analysis (see Wear Metals). Not all particles can be measured by the method used to determine wear metals. Therefore, excessive particulate contamination can be missed if Particle Counting is not a routine part of your oil analysis program.

The Gregory Poole S•O•S Program is one of the few oil analysis programs that offer this as part of their overall package for all non-engine compartments (there is too much soot in engines to use this test on those samples).

Oil Quality (FTIR Spectroscopy)

FTIR stands for Fourior Transform InfraRed. This sophisticated instrumental technique allows the S•O•S lab to determine numerous oil conditions. For the analysis to be effective, it is necessary to have a sample of your new oil to use as a reference.

Oil Degradation:

• As your oil 'ages', several things happen to it. The oil chemically reacts with the air. If it combines with oxygen, it is called Oxidation. If it combines with nitrogen, it is called Nitration. Both cause the oil to thicken (see Viscosity) and cause a build up of varnish-like material on component parts.
• Another type of degradation occurs as a result of a 'blow-by' of combustion products into the oil. These combustion products (and the fuel itself) contain sulfur. This sulfur reacts to form acidic products which can build up and cause severe corrosion. The formation of these products is called Sulfation.

Fluid Entry:

• In addition to the oil in your equipment, there are usually 3 other fluids flowing through the systems: water, antifreeze and diesel fuel. All 3 are critical to the proper functioning of your equipment - none belong in your oil! FTIR will detect the presence of this fluid entry and alert the S•O•S lab personnel to perform other physical tests to confirm their presence.

Viscosity

Viscosity is the measure of the oil's ability to lubricate. If the viscosity changes, the oil no longer lubricates and is unable to protect surfaces efficiently.

• If the oil is running too hot or if the oil change interval is extended, the oil can oxidize. This will cause the oil to thicken and the viscosity to increase.
• If fuel is getting into the crankcase, the oil will be thinned. This will cause the viscosity to drastically decrease.

The S•O•S Program measures the viscosity of all engine samples. Any change, either an increase or a decrease, will be detected and corrective action can then be initiated.

For more information concerning Gregory Poole Equipment Company's S•O•S Fluid Analysis Program

call (800) 451-7278