Page 1 of 90
CWEA Mechanical Technologist Grade 3 Exam
Questions with Correct Answers and explanations
LATEST THIS YEAR -JUST RELEASED
Below is a summarized exam coverage for the CWEA Mechanical Technologist Grade 3 Exam, followed
by 200 randomized, scenario-based MCQs directly aligned with the exam. No subtopics or domain
headings are used—just questions, answers, and concise rationales. Questions are based on the CWEA
Mechanical Technologist Grade 3 Need-to-Know criteria, covering maintenance, repair, installation,
troubleshooting, safety, hydraulics, pneumatics, pumps, blowers, conveyors, gearboxes, bearings,
lubrication, alignment, vibration analysis, thermodynamics, instrumentation, process control, welding,
rigging, confined space, lockout/tagout, and California OSHA (Cal/OSHA) regulations.
1. A mechanical technologist is troubleshooting a centrifugal pump that delivers low flow at shutoff
head. The most likely cause is:
A) Worn impeller
B) Air leak in suction line
C) Reverse rotation
D) Discharge valve closed
Answer: C – Reverse rotation reduces flow and head; a closed discharge valve would give normal shutoff
head with no flow.
, Page 2 of 90
2. A technician is aligning a motor and pump using a dial indicator. The vertical parallel misalignment is
0.010 inches. The acceptable tolerance for a flexible coupling is typically:
A) 0.002 inches
B) 0.005 inches
C) 0.010 inches
D) 0.020 inches
Answer: B – Most flexible couplings allow up to 0.005 inches parallel misalignment.
3. A gearbox has a high oil temperature alarm. The first check should be:
A) Oil level and condition
B) Motor amperage
C) Bearing vibration
D) Coupling alignment
Answer: A – Low oil level, wrong viscosity, or contaminated oil is the most common cause of
overheating.
, Page 3 of 90
4. A technician is replacing a V-belt. The new belt should be tensioned so that deflection per 12 inches of
span is:
A) 1/64 inch
B) 1/32 inch
C) 1/16 inch
D) 1/8 inch
Answer: C – *General rule: 1/16 inch deflection per 12 inches of span for standard V-belts.*
5. A centrifugal blower is vibrating severely. The vibration is at 1× running speed and increases with
load. The most likely cause is:
A) Unbalance
B) Misalignment
C) Bearing wear
D) Looseness
Answer: A – 1× running speed vibration that increases with load indicates unbalance.
, Page 4 of 90
6. A technician is performing a confined space entry. The oxygen level must be at least:
A) 19.5%
B) 20.0%
C) 20.5%
D) 21.0%
Answer: A – *Cal/OSHA requires oxygen between 19.5% and 23.5% for entry.*
7. A hydraulic system has a pump that is noisy and the fluid is foamy. The most likely cause is:
A) Low fluid level or air leak in suction line
B) Worn pump
C) Clogged filter
D) Relief valve set too high
Answer: A – Air entering the suction line causes cavitation and foaming.
8. A technician is lubricating a bearing with a grease gun. The bearing should be purged until:
A) Old grease is forced out of the seal
B) The grease gun stops
CWEA Mechanical Technologist Grade 3 Exam
Questions with Correct Answers and explanations
LATEST THIS YEAR -JUST RELEASED
Below is a summarized exam coverage for the CWEA Mechanical Technologist Grade 3 Exam, followed
by 200 randomized, scenario-based MCQs directly aligned with the exam. No subtopics or domain
headings are used—just questions, answers, and concise rationales. Questions are based on the CWEA
Mechanical Technologist Grade 3 Need-to-Know criteria, covering maintenance, repair, installation,
troubleshooting, safety, hydraulics, pneumatics, pumps, blowers, conveyors, gearboxes, bearings,
lubrication, alignment, vibration analysis, thermodynamics, instrumentation, process control, welding,
rigging, confined space, lockout/tagout, and California OSHA (Cal/OSHA) regulations.
1. A mechanical technologist is troubleshooting a centrifugal pump that delivers low flow at shutoff
head. The most likely cause is:
A) Worn impeller
B) Air leak in suction line
C) Reverse rotation
D) Discharge valve closed
Answer: C – Reverse rotation reduces flow and head; a closed discharge valve would give normal shutoff
head with no flow.
, Page 2 of 90
2. A technician is aligning a motor and pump using a dial indicator. The vertical parallel misalignment is
0.010 inches. The acceptable tolerance for a flexible coupling is typically:
A) 0.002 inches
B) 0.005 inches
C) 0.010 inches
D) 0.020 inches
Answer: B – Most flexible couplings allow up to 0.005 inches parallel misalignment.
3. A gearbox has a high oil temperature alarm. The first check should be:
A) Oil level and condition
B) Motor amperage
C) Bearing vibration
D) Coupling alignment
Answer: A – Low oil level, wrong viscosity, or contaminated oil is the most common cause of
overheating.
, Page 3 of 90
4. A technician is replacing a V-belt. The new belt should be tensioned so that deflection per 12 inches of
span is:
A) 1/64 inch
B) 1/32 inch
C) 1/16 inch
D) 1/8 inch
Answer: C – *General rule: 1/16 inch deflection per 12 inches of span for standard V-belts.*
5. A centrifugal blower is vibrating severely. The vibration is at 1× running speed and increases with
load. The most likely cause is:
A) Unbalance
B) Misalignment
C) Bearing wear
D) Looseness
Answer: A – 1× running speed vibration that increases with load indicates unbalance.
, Page 4 of 90
6. A technician is performing a confined space entry. The oxygen level must be at least:
A) 19.5%
B) 20.0%
C) 20.5%
D) 21.0%
Answer: A – *Cal/OSHA requires oxygen between 19.5% and 23.5% for entry.*
7. A hydraulic system has a pump that is noisy and the fluid is foamy. The most likely cause is:
A) Low fluid level or air leak in suction line
B) Worn pump
C) Clogged filter
D) Relief valve set too high
Answer: A – Air entering the suction line causes cavitation and foaming.
8. A technician is lubricating a bearing with a grease gun. The bearing should be purged until:
A) Old grease is forced out of the seal
B) The grease gun stops
