CLS CLS Oil Analysis & Condition Monitoring

Question 1

Which oil analysis test is primarily used to detect the presence of water contamination in a lubricant?

Accepted Answer

Crackle test

Answer

Viscosity index measurement

Answer

Acid number titration

Answer

Flash point test

Question 2

What does a rising ferrous density (FD) value in an oil analysis report most likely indicate?

Accepted Answer

Increased wear of ferrous metal components

Answer

Improved lubricant performance

Answer

Decreased oil oxidation

Answer

Lower contamination levels

Question 3

The viscosity of an in-service lubricant has increased by 25% from its new-oil baseline. What is the most probable cause?

Accepted Answer

Oxidation and thermal degradation

Answer

Water dilution

Answer

Fuel dilution

Answer

Coolant contamination

Question 4

Which elemental spectroscopy technique is most commonly used in oil analysis to identify wear metals?

Accepted Answer

Inductively Coupled Plasma (ICP)

Answer

X-ray fluorescence (XRF) of bulk oil

Answer

Atomic absorption spectroscopy of new oil

Answer

Infrared spectroscopy

Question 5

A Total Base Number (TBN) test on a diesel engine oil shows a value that has dropped to less than 50% of the new-oil TBN. What does this indicate?

Accepted Answer

The oil's acid-neutralizing capacity is significantly depleted

Answer

The oil viscosity has improved

Answer

The oil contains excess additives

Answer

The oil is in excellent condition

Question 6

In particle count analysis using ISO 4406, a code of 18/16/13 describes contamination levels for particles sized at which thresholds?

Accepted Answer

≥4 µm, ≥6 µm, ≥14 µm

Answer

≥2 µm, ≥5 µm, ≥10 µm

Answer

≥5 µm, ≥10 µm, ≥20 µm

Answer

≥1 µm, ≥5 µm, ≥15 µm