ICML Machine Lubricant Analyst (MLA) Level 2 –
Exam Questions And Answers Practice Questions
with Solutions Newest | Already Graded A+.
Below is a comprehensive set of continuing practice questions for the International
Council for Machinery Lubrication (ICML) MLA Level II certification exam. The exam is
benchmarked against ISO 18436-4 and consists of 100 multiple-choice questions over 3
hours . Correct answers are in italic with explanations.
SECTION 1: OIL SAMPLING (29% of Exam)
Q1: For a journal bearing system with a pressurized circulation loop, the most
representative sample for machine condition is obtained from which location?
A) Immediately after the main pump discharge
B) Downstream of the cooler and filters, before entering the bearings
C) Bearing drain line back to the reservoir
D) Reservoir bottom via a drop-tube
Answer: C) Bearing drain line back to the reservoir. The bearing drain line carries wear
debris directly from the bearings before it settles in the reservoir, giving the earliest
indication of bearing condition. Oil after the filter has been cleaned and is less
representative .
Q2: During a drop-tube sampling procedure, the tube is inserted to the bottom
and then withdrawn slightly. What is the main purpose of withdrawing slightly?
A) To increase the oil flow rate into the bottle
B) To ensure the tube end is exactly at the mid-point
C) To avoid sucking up settled sediment and water
D) To mix the oil near the top of the reservoir
,Answer: C) To avoid sucking up settled sediment and water. The initial contact with the
tank floor can disturb settled debris; retracting the tube 1-2 cm prevents aspiration of
bottom sludge and water, giving a more representative bulk sample .
Q3: Which factor is most critical to manage when taking a sample for particle
count analysis?
A) Minimizing exposure to direct sunlight
B) Ensuring the oil is at its highest operating temperature
C) Avoiding secondary contamination from the sampling apparatus and environment
D) Using only glass bottles to prevent static charge
Answer: C) Avoiding secondary contamination from the sampling apparatus and
environment. Particle counting is extremely sensitive to contamination; even a tiny
amount of dirt introduced during sampling can cause a false high ISO code, masking true
system cleanliness .
Q4: Which action is most likely to cause cross-contamination when sampling
multiple machines in succession?
A) Using a new sample bottle for each machine
B) Reusing the same sampling tubing without thorough flushing between machines
C) Labeling bottles after they are filled
D) Sampling from a dedicated valve on each machine
Answer: B) Reusing the same sampling tubing without thorough flushing between
machines. Residual oil and particles from one machine cling to the tubing interior; if not
replaced or properly flushed, they transfer into the next sample, mixing oils and creating
misleading data .
Q5: For the most repeatable and reliable oil analysis trending, which sampling
method should be used?
A) Bottom drain valve sample
B) Mid-sump drop-tube sample
C) Magnet-extracted sample from the drain plug
D) Occasional bottom drain sample without flushing
Answer: B) Mid-sump drop-tube sample. Consistent mid-sump drop-tube sampling
ensures repeatable trending of wear particles and contamination over time, whereas
bottom or magnet samples are not representative of bulk circulating oil .
Q6: In a large circulating lubrication system, a sample taken from the oil cooler
drain plug is likely to show what characteristic?
A) Lower particle counts because the cooler is a low-pressure zone
, B) Excessively low viscosity due to cooler shear
C) Higher moisture content if there is a cooler leak
D) Increased additive depletion due to heat
Answer: C) Higher moisture content if there is a cooler leak. Sampling from a cooler drain
may detect water or coolant ingress due to a leak in the cooler, which would show
elevated moisture not seen in a normally sampled return line .
SECTION 2: LUBRICANT HEALTH MONITORING (21% of
Exam)
Q7: What is the primary reason for using a clear or translucent sample bottle for
certain lubricant analyses?
A) It costs less than opaque bottles
B) It allows visual inspection for free water, sediment, or color changes
C) UV light can pass through and sterilize the sample
D) Plastic bottles do not absorb additives
Answer: B) It allows visual inspection for free water, sediment, or color changes without
opening the container. Visual inspection in a transparent bottle can immediately reveal
gross contamination, water separation, or darkening before laboratory testing .
Q8: An increase in the Acid Number of a turbine oil accompanied by a decrease in
residual RPVOT most strongly indicates:
A) Water contamination only
B) Progressive oxidation and antioxidant depletion
C) Additive dropout without oxidation
D) Fuel dilution
Answer: B) Progressive oxidation and antioxidant depletion. Oxidation generates acidic
by-products that raise the acid number while simultaneously consuming antioxidant
additives, thereby reducing residual RPVOT life .
Q9: Which additive element is most commonly associated with extreme-pressure
(EP) additives in industrial gear oils?
A) Calcium
B) Phosphorus or sulfur
Exam Questions And Answers Practice Questions
with Solutions Newest | Already Graded A+.
Below is a comprehensive set of continuing practice questions for the International
Council for Machinery Lubrication (ICML) MLA Level II certification exam. The exam is
benchmarked against ISO 18436-4 and consists of 100 multiple-choice questions over 3
hours . Correct answers are in italic with explanations.
SECTION 1: OIL SAMPLING (29% of Exam)
Q1: For a journal bearing system with a pressurized circulation loop, the most
representative sample for machine condition is obtained from which location?
A) Immediately after the main pump discharge
B) Downstream of the cooler and filters, before entering the bearings
C) Bearing drain line back to the reservoir
D) Reservoir bottom via a drop-tube
Answer: C) Bearing drain line back to the reservoir. The bearing drain line carries wear
debris directly from the bearings before it settles in the reservoir, giving the earliest
indication of bearing condition. Oil after the filter has been cleaned and is less
representative .
Q2: During a drop-tube sampling procedure, the tube is inserted to the bottom
and then withdrawn slightly. What is the main purpose of withdrawing slightly?
A) To increase the oil flow rate into the bottle
B) To ensure the tube end is exactly at the mid-point
C) To avoid sucking up settled sediment and water
D) To mix the oil near the top of the reservoir
,Answer: C) To avoid sucking up settled sediment and water. The initial contact with the
tank floor can disturb settled debris; retracting the tube 1-2 cm prevents aspiration of
bottom sludge and water, giving a more representative bulk sample .
Q3: Which factor is most critical to manage when taking a sample for particle
count analysis?
A) Minimizing exposure to direct sunlight
B) Ensuring the oil is at its highest operating temperature
C) Avoiding secondary contamination from the sampling apparatus and environment
D) Using only glass bottles to prevent static charge
Answer: C) Avoiding secondary contamination from the sampling apparatus and
environment. Particle counting is extremely sensitive to contamination; even a tiny
amount of dirt introduced during sampling can cause a false high ISO code, masking true
system cleanliness .
Q4: Which action is most likely to cause cross-contamination when sampling
multiple machines in succession?
A) Using a new sample bottle for each machine
B) Reusing the same sampling tubing without thorough flushing between machines
C) Labeling bottles after they are filled
D) Sampling from a dedicated valve on each machine
Answer: B) Reusing the same sampling tubing without thorough flushing between
machines. Residual oil and particles from one machine cling to the tubing interior; if not
replaced or properly flushed, they transfer into the next sample, mixing oils and creating
misleading data .
Q5: For the most repeatable and reliable oil analysis trending, which sampling
method should be used?
A) Bottom drain valve sample
B) Mid-sump drop-tube sample
C) Magnet-extracted sample from the drain plug
D) Occasional bottom drain sample without flushing
Answer: B) Mid-sump drop-tube sample. Consistent mid-sump drop-tube sampling
ensures repeatable trending of wear particles and contamination over time, whereas
bottom or magnet samples are not representative of bulk circulating oil .
Q6: In a large circulating lubrication system, a sample taken from the oil cooler
drain plug is likely to show what characteristic?
A) Lower particle counts because the cooler is a low-pressure zone
, B) Excessively low viscosity due to cooler shear
C) Higher moisture content if there is a cooler leak
D) Increased additive depletion due to heat
Answer: C) Higher moisture content if there is a cooler leak. Sampling from a cooler drain
may detect water or coolant ingress due to a leak in the cooler, which would show
elevated moisture not seen in a normally sampled return line .
SECTION 2: LUBRICANT HEALTH MONITORING (21% of
Exam)
Q7: What is the primary reason for using a clear or translucent sample bottle for
certain lubricant analyses?
A) It costs less than opaque bottles
B) It allows visual inspection for free water, sediment, or color changes
C) UV light can pass through and sterilize the sample
D) Plastic bottles do not absorb additives
Answer: B) It allows visual inspection for free water, sediment, or color changes without
opening the container. Visual inspection in a transparent bottle can immediately reveal
gross contamination, water separation, or darkening before laboratory testing .
Q8: An increase in the Acid Number of a turbine oil accompanied by a decrease in
residual RPVOT most strongly indicates:
A) Water contamination only
B) Progressive oxidation and antioxidant depletion
C) Additive dropout without oxidation
D) Fuel dilution
Answer: B) Progressive oxidation and antioxidant depletion. Oxidation generates acidic
by-products that raise the acid number while simultaneously consuming antioxidant
additives, thereby reducing residual RPVOT life .
Q9: Which additive element is most commonly associated with extreme-pressure
(EP) additives in industrial gear oils?
A) Calcium
B) Phosphorus or sulfur
