CLS CLS Oil Analysis & Condition Monitoring 2

Question 1

Which oil analysis parameter is the best early indicator of coolant ingress into an engine lubricant?

Accepted Answer

Elevated sodium and potassium levels

Answer

Coolant contains ethylene glycol stabilized with sodium and potassium additives, which appear in oil analysis when a seal fails.

Question 2

What is the primary purpose of establishing an oil analysis baseline for a new machine?

Accepted Answer

To set reference values for detecting future abnormal changes

Answer

Baseline samples capture the 'normal' oil condition so future results can be trended and anomalies detected early.

Question 3

Patch test colorimetry in used oil analysis is primarily used to evaluate which property?

Accepted Answer

Varnish potential and deposit-forming tendency

Answer

The membrane patch colorimetry (MPC) test quantifies insoluble oxidation by-products that indicate varnish formation risk.

Question 4

Elevated silicon levels found during routine oil analysis most often point to which contamination source?

Accepted Answer

Airborne dust and dirt ingression

Answer

Silicon is a primary element in silica (sand and dust), making elevated silicon a classic indicator of inadequate air filtration.

Question 5

According to ASTM D445, kinematic viscosity of a lubricant is measured at which two standard temperatures?

Accepted Answer

40°C and 100°C

Answer

ASTM D445 standardizes kinematic viscosity measurement at 40°C (operational reference) and 100°C (high-temperature reference).

(CLS) Certified Lubrication Specialist Practice Test