Identifying Engine Oil Contamination

If your organization operates a large fleet, then you know the amount of time, money and resources required to manage and maintain it. Routine oil analysis can help you look ahead, predict breakdowns and sustain fleet health.

Oil analysis can identify contaminants in engine oil that cause excessive wear on vehicle components and often lead to costly repairs and unnecessary downtime. Here are the top four engine oil contaminants, how they are most commonly introduced into lubrication systems, how to test for them and what those tests mean to the health and longevity of your fleet’s engines.

View the Infographic


Abrasives

Causes
Of these four, abrasives are, by far, the most damaging to lubrication systems and engine components. Common abrasives, in the form of dust and dirt, can enter the lubrication system through leaks in the air intake system, seals, ventilation system or from a contaminated supply of new oil. As they circulate within the oil, they cause wear to metal components, which can produce additional wear particles that may cause even greater damage.

Detection
Concentrations of silicon and aluminum identified by ICP (inductively-coupled plasma) spectroscopy are typically indicative of dust and dirt contamination. ICP detects wear, contaminant and additive elements present in oil by ionizing the sample and using a mass spectrometer to measure levels of concentration.

Risk
If abrasive contaminants are left unchecked, extensive, sometimes irreparable, engine and component wear can occur reducing vehicle reliability and longevity and increasing maintenance, repair and replacement costs.


Water

Causes
Water is the second most common contaminant damaging to engine oil. Bad seals, system vents, condensation or a contaminated new oil supply are typically responsible for water ingression.

Detection
The presence of water can be detected by a “crackle” test or through FTIR (Fourier Transform Infrared Spectrometry) and is reported in % volume. How much water is actually present can be determined by the Karl Fisher titration method and is reported in parts per million (ppm).

Risk
Water contamination can reduce lubricity and lead to increased component wear and shorter component life. Water also promotes the formation of acids that corrode pistons, rings and liners.


Coolant

Causes
Coolant can find its way into lubrications systems through a blown head gasket, leaking intake gaskets or cracked cylinder heads.

Detection
Coolant contamination is best identified through an elemental analysis by ICP as potassium, sodium and boron are indications that a type of coolant formulation is present.

Risk
Coolant contamination can severely damage engine bearings, pistons, rings and liners. It reduces oil viscosity and can thicken it to a “sludge” allowing the formation of acids that will attack engine component metals.


Fuel

Causes
When unburned diesel fuel makes its way past the rings and into the engine oil in the crankcase, fuel contamination, or fuel dilution, results. Fuel dilution can decrease oil viscosity and lubricity even at very low levels, increasing both bearing wear and the potential for bearing failure.

Detection
Even a moderate decrease in oil viscosity can indicate the presence of fuel contamination. As testing for fuel dilution is the measurement of one petroleum product within another, it is most accurately identified by gas chromatography (GC), a process that separates the mixture by vaporizing the sample and measuring each component released.

Risk
Fuel contamination is a serious issue that makes early detection vital to maintaining component health. As diesel fuel lowers oil viscosity, it reduces the corrosion protection of its additives and accelerates component wear. Extremely severe cases can result in a crankcase explosion.


Oil analysis saves fleet manaers time and money in equipment repairs, replacement and lost revenue from unnecessary downtime. It plays a vital role in effectively managing fleet operations. From lowering maintenance costs to reducing engine failures, using oil analysis to identify contamination in its earliest stages can pinpoint the issues putting your fleet at risk.