CPT Maintenance & Troubleshooting 3

Question 1

A hydraulic system loses pressure gradually when the pump is stopped and valves are closed. This symptom indicates:

Accepted Answer

Internal leakage past a relief valve or cylinder seals

Answer

Gradual pressure drop with pump off and valves closed points to internal leakage past worn seals or a leaking relief valve.

Question 2

What is the primary purpose of a lockout/tagout (LOTO) procedure before performing maintenance on machinery?

Accepted Answer

To prevent accidental energization that could injure workers

Answer

LOTO procedures ensure all energy sources are isolated and locked before maintenance begins, preventing accidental startup or energy release.

Question 3

A three-phase motor fails to start and hums loudly. One likely cause is:

Accepted Answer

An open phase (single-phasing condition)

Answer

Single-phasing occurs when one of the three supply phases is lost, causing the motor to hum and fail to start because it cannot develop sufficient starting torque.

Question 4

Which type of bearing failure leaves a pattern of evenly spaced pits or fluting marks on the raceway?

Accepted Answer

Electrical pitting from stray current

Answer

Electrical pitting (fluting) creates regularly spaced groove marks on bearing raceways caused by stray electrical current passing through the bearing.

Question 5

A gear drive emits a high-pitched whine that changes pitch with speed. This symptom most likely indicates:

Accepted Answer

Insufficient lubrication between gear teeth

Answer

A high-pitched whine that tracks with speed in a gearbox is a classic sign of inadequate lubrication causing metal-to-metal contact between gear teeth.

(CPT) Certified Production Technician Practice Test

(CPT) Certified Production Technician Practice Test

CPT Maintenance & Troubleshooting 3