Engine Testing

Engine manufacturers use Spectro Scientific oil analysis instruments to assist in engine testing during new product development, testing engines during manufacturing run-in, and for qualifying new lubricants. Engines include:

Wear

Break-in wear - During the new engine break-in period, larger adhesive (sliding) wear particles are generated at a higher rate than during normal operating conditions. Continuously trending the sliding wear rate helps engineers understand the engine break-in pattern.

Normal wear – Running engines continuously generates small rubbing wear particles from all the moving parts inside. Elemental analysis is the best method to analyze small wear particles and trace them back to the source of wear through elemental identification.

Chemistry

Total Acid Number (TAN) - TAN is measured to determine the corrosive potential of lubrication oils. If the TAN gets too high the oil can induce corrosion of machine parts and should be changed.

Total Base Number (TBN) - TBN measures the amount of active acid neutralizing additive left in a sample of oil. The TBN is useful for people who want to extend their oil usage far beyond the normal range. The TBN of a used oil can aid the user in determining how much reserve additive the oil has left to neutralize acids. The lower the TBN reading, the less active additive the oil has left.

Viscosity - The main function of lubrication oil is to create and maintain a lubrication film between two moving metal surfaces. Ensuring the viscosity is within recommended ranges is one of the most important tests one can run on lube oil.

Oxidation, Nitration, Sulfation - Lubricating oil at elevated temperatures can react with oxygen and nitrogen in the atmosphere, as well as sulfur in fuel, to form undesirable by-products that can affect the oil's viscosity and lead to corrosion or damage of equipment.

Contamination

Fuel Dilution - Fuel dilution in oil is a condition caused by excess, unburned fuel mixing with engine oil in an engine crankcase. Hydrocarbon-based fuel, usually with a lower vapor pressure than the lubricant, has a thinning effect, lowering the oil viscosity. Oil film strength is reduced, increasing the cylinder liner and bearing wear.

Soot - Soot is a product of diesel combustion and has always been found in engine oils. Soot can use up an oil's additives and deposit on vital engine surfaces.

Glycol - Glycol is found in engine coolant. If glycol is found in engine oil it typically indicates there is a leak in the engine that needs to be addressed.