LADWP Mechanical Helper Exam (Class
3771) Exam — Representative Questions
And Answers Complete Study Guide
Exam.Instant Pdf Download.
Question 1 (Machine Guarding)
A mechanical helper is asked to remove a guard from a rotating machine so a journey-
level mechanic can inspect the equipment. What should the helper do FIRST?
A) Remove the guard immediately to save time
B) Ask another helper to hold the guard
C) Verify that the equipment is properly isolated before removing the guard
D) Remove the guard only if the machine is running slowly
Correct Answer: C
Rotating equipment must be made safe before guards are removed. Isolation prevents
unexpected movement and exposure to moving parts. Removing a guard while equipment
could energize is a serious safety violation .
Question 2 (Pipe Cutting and Threading)
A pipe must be cut and threaded for installation. Which sequence is most appropriate?
A) Thread the pipe, then cut it to length
B) Measure, cut, deburr, and then thread the pipe
C) Heat the pipe before measuring
D) Thread both ends before cutting
Correct Answer: B
Accurate measurement and cutting should precede threading. Deburring removes sharp
edges and helps produce a clean thread and proper connection .
,Question 3 (Drill Press Operation)
A drill press begins producing a hole that is larger than the selected drill bit. What is the
most likely concern?
A) The workpiece is too clean
B) The drill press table is too low
C) The workpiece may not be secure or the drill may be damaged
D) The cutting speed is always too slow
Correct Answer: C
An improperly secured workpiece or damaged/bent tooling can cause the drill to wander
and produce an oversized hole. Workpieces must be clamped securely before drilling .
Question 4 (Grinder Safety)
Before operating a portable grinder, which condition requires immediate correction?
A) The workpiece is painted
B) The operator is wearing safety glasses
C) The grinding wheel has a visible crack
D) The grinder has a grounded plug
Correct Answer: C
A cracked grinding wheel can fail catastrophically during operation and must not be used.
Inspect wheels for damage before every use .
Question 5 (Workpiece Security)
A mechanic tells a helper to hold a component while it is being drilled. The component
begins shifting. What is the safest response?
A) Hold it harder with one hand
B) Continue drilling at reduced speed
C) Stop and secure the component properly
D) Ask the mechanic to drill faster
Correct Answer: C
The workpiece should be secured with an appropriate clamp, vise, or fixture rather than
held by hand. Hand-holding a shifting workpiece risks injury from the rotating bit or flying
material .
,Question 6 (Wrench Safety)
A wrench slips while loosening a fastener. Which action best reduces the likelihood of
another slip?
A) Use a longer unrelated tool
B) Strike the wrench continuously
C) Use the correctly sized wrench fully engaged on the fastener
D) Hold the wrench at an angle
Correct Answer: C
Proper fit and full engagement provide better control and reduce slipping. An undersized
or angled wrench is more likely to slip and cause injury .
Question 7 (Suspended Loads)
A helper is assisting with a suspended machine component. The load begins swinging.
What should the helper do?
A) Push the load while standing beneath it
B) Grab the load with both hands
C) Keep clear of the suspended load and control the operation as directed
D) Stand underneath it to stabilize it
Correct Answer: C
Personnel should remain outside the danger zone of suspended loads. Loads should be
controlled using proper rigging and procedures, never by standing beneath or grabbing a
swinging load .
Question 8 (Hoist Capacity)
A hoist is rated for 2,000 pounds. A component weighs approximately 2,100 pounds.
What should the helper do?
A) Lift it because the difference is small
B) Lift it slowly
C) Use two people to pull on it
D) Do not lift it with that hoist
, Correct Answer: D
The rated capacity must not be exceeded. Appropriate lifting equipment with sufficient
capacity is required. Overloading a hoist can cause catastrophic failure .
Question 9 (Tool Selection)
Which tool is generally most appropriate for gripping and turning a hexagonal fastener?
A) Pipe wrench
B) Box or socket wrench of the correct size
C) Slip-joint pliers
D) Adjustable wrench set to maximum opening
Correct Answer: B
A properly sized wrench or socket provides positive engagement with the fastener and
reduces damage. Pliers and pipe wrenches are not designed for hexagonal fasteners and
can round the edges .
Question 10 (Deburring Purpose)
Why is deburring performed after cutting pipe?
A) To increase pipe weight
B) To reduce pipe diameter permanently
C) To remove sharp edges and help maintain proper flow and connection quality
D) To make the pipe magnetic
Correct Answer: C
Deburring removes sharp internal and external edges and helps prevent restrictions or
damage during assembly. Sharp edges can cut seals, impede flow, and cause injury during
handling .
Question 11 (Power Tool Safety)
A portable power tool has a damaged electrical cord with exposed conductors. What
should the helper do?
A) Wrap it with any available tape and continue
3771) Exam — Representative Questions
And Answers Complete Study Guide
Exam.Instant Pdf Download.
Question 1 (Machine Guarding)
A mechanical helper is asked to remove a guard from a rotating machine so a journey-
level mechanic can inspect the equipment. What should the helper do FIRST?
A) Remove the guard immediately to save time
B) Ask another helper to hold the guard
C) Verify that the equipment is properly isolated before removing the guard
D) Remove the guard only if the machine is running slowly
Correct Answer: C
Rotating equipment must be made safe before guards are removed. Isolation prevents
unexpected movement and exposure to moving parts. Removing a guard while equipment
could energize is a serious safety violation .
Question 2 (Pipe Cutting and Threading)
A pipe must be cut and threaded for installation. Which sequence is most appropriate?
A) Thread the pipe, then cut it to length
B) Measure, cut, deburr, and then thread the pipe
C) Heat the pipe before measuring
D) Thread both ends before cutting
Correct Answer: B
Accurate measurement and cutting should precede threading. Deburring removes sharp
edges and helps produce a clean thread and proper connection .
,Question 3 (Drill Press Operation)
A drill press begins producing a hole that is larger than the selected drill bit. What is the
most likely concern?
A) The workpiece is too clean
B) The drill press table is too low
C) The workpiece may not be secure or the drill may be damaged
D) The cutting speed is always too slow
Correct Answer: C
An improperly secured workpiece or damaged/bent tooling can cause the drill to wander
and produce an oversized hole. Workpieces must be clamped securely before drilling .
Question 4 (Grinder Safety)
Before operating a portable grinder, which condition requires immediate correction?
A) The workpiece is painted
B) The operator is wearing safety glasses
C) The grinding wheel has a visible crack
D) The grinder has a grounded plug
Correct Answer: C
A cracked grinding wheel can fail catastrophically during operation and must not be used.
Inspect wheels for damage before every use .
Question 5 (Workpiece Security)
A mechanic tells a helper to hold a component while it is being drilled. The component
begins shifting. What is the safest response?
A) Hold it harder with one hand
B) Continue drilling at reduced speed
C) Stop and secure the component properly
D) Ask the mechanic to drill faster
Correct Answer: C
The workpiece should be secured with an appropriate clamp, vise, or fixture rather than
held by hand. Hand-holding a shifting workpiece risks injury from the rotating bit or flying
material .
,Question 6 (Wrench Safety)
A wrench slips while loosening a fastener. Which action best reduces the likelihood of
another slip?
A) Use a longer unrelated tool
B) Strike the wrench continuously
C) Use the correctly sized wrench fully engaged on the fastener
D) Hold the wrench at an angle
Correct Answer: C
Proper fit and full engagement provide better control and reduce slipping. An undersized
or angled wrench is more likely to slip and cause injury .
Question 7 (Suspended Loads)
A helper is assisting with a suspended machine component. The load begins swinging.
What should the helper do?
A) Push the load while standing beneath it
B) Grab the load with both hands
C) Keep clear of the suspended load and control the operation as directed
D) Stand underneath it to stabilize it
Correct Answer: C
Personnel should remain outside the danger zone of suspended loads. Loads should be
controlled using proper rigging and procedures, never by standing beneath or grabbing a
swinging load .
Question 8 (Hoist Capacity)
A hoist is rated for 2,000 pounds. A component weighs approximately 2,100 pounds.
What should the helper do?
A) Lift it because the difference is small
B) Lift it slowly
C) Use two people to pull on it
D) Do not lift it with that hoist
, Correct Answer: D
The rated capacity must not be exceeded. Appropriate lifting equipment with sufficient
capacity is required. Overloading a hoist can cause catastrophic failure .
Question 9 (Tool Selection)
Which tool is generally most appropriate for gripping and turning a hexagonal fastener?
A) Pipe wrench
B) Box or socket wrench of the correct size
C) Slip-joint pliers
D) Adjustable wrench set to maximum opening
Correct Answer: B
A properly sized wrench or socket provides positive engagement with the fastener and
reduces damage. Pliers and pipe wrenches are not designed for hexagonal fasteners and
can round the edges .
Question 10 (Deburring Purpose)
Why is deburring performed after cutting pipe?
A) To increase pipe weight
B) To reduce pipe diameter permanently
C) To remove sharp edges and help maintain proper flow and connection quality
D) To make the pipe magnetic
Correct Answer: C
Deburring removes sharp internal and external edges and helps prevent restrictions or
damage during assembly. Sharp edges can cut seals, impede flow, and cause injury during
handling .
Question 11 (Power Tool Safety)
A portable power tool has a damaged electrical cord with exposed conductors. What
should the helper do?
A) Wrap it with any available tape and continue
