The quiz below should be administered to all maintenance personnel responsible for hydraulic equipment.  A score of less than 80% is a strong indication that GPM’s Maintenance Hydraulic Troubleshooting workshop could reap significant savings in unnecessary parts changing and plant downtime.  

Click Here To Tell A Friend About Our Online Hydraulic Quiz

It is recommended that any student who achieves less than 70% on this quiz attend our Maintenance Hydraulic Troubleshooting workshop.

2. Pressure in a hydraulic system is generated by ___________ to flow. 
acceptance
immunity
resistance 
compliance 

3. Force = __________ x ____________ 
flow x distance
work x time 
pressure x flow 
pressure x area 

4. Most of the energy not used to move the load in a hydraulic system turns into____________.
heat
light 
potential
reserve 

5. The relief valve is a normally closed valve. The term "closed" means that in the power off condition the valve is:
Open to flow
Closed to flow 
Adjustable 
Non-adjustable

6. When the compensator setting of a pressure compensating hydraulic pump is reached the pump volume will: 
Dump back to tank through the relief valve
Dump back to tank through the compensator 
Be reduced to only what the system needs
Be reduced until the pressure drops to near 0

7. What is the number one reason why pumps cavitate? 
Low fluid level 
Air leak in the suction line
Plugged suction strainer
Electric motor driving at too high of an a RPM 

8. What five characteristics does the valve below have?

Normally open, 4-way, 2 position, detent, hydraulically actuated 
Normally open, two-way, three position, spring return, solenoid actuated 
Normally closed, two position, two-way, spring return, solenoid actuated 
Normally open, two position, two-way, spring return, hydraulically actuated 

A

B

C

All of the choices would work equally well

A

B

Both valves are the same size
Either valve could be larger

Normally open
Normally closed
Non-adjustable
Solenoid actuated

12. What type gas should normally be used to charge an accumulator?
Oxygen
Compressed air
Nitrogen
Acetylene

13. In precharging an accumulator used for volume, the precharge pressure should be
The same as the compensator setting
The same as the relief valve setting
One half the maximum system pressure
90% of the maximum system pressure

14. When using a hydraulic accumulator for volume and the accumulator is operating properly, heat should be felt:
All over the accumulator shell
In the lower 2/3rds of the shell
At the bottom of the shell only
At the dump valve only

15. When using an accumulator for shock it should be:
Installed as far as possible away from the component it protects
Pre-charged approximately 1000 PSI above the maximum system working pressure
One gallon or smaller in size
Mounted horizontally

16. The symbol shown below indicates:

A variable orifice type flow control
A fixed orifice flow control
A pressure compensating, variable orifice flow control 
A temperature and pressure compensated variable flow control 

17. A purpose of the crossport relief valve in a hydraulic motor circuit is to:
Absorb shock when the motor is first started
Heat up the hydraulic oil
Limit the maximum flow to the motor
To serve as a back up in case the pump compensator fails

18. Servo and proportional valves operate from a:
Variable AC voltage
Variable DC voltage
Fixed DC voltage
Fixed AC voltage

19. A servo valve should be nulled when:
The electrics are connected
The system is first turned on
The electrics are disconnected
With the hydraulic pump turned off

20. The purpose of a Temposonic transducer is:
To electrically indicate the cylinder position to the PLC
Send a variable DC voltage to the servo valve coil
Convert an AC voltage to a variable DC voltage
Cool the oil in the linear positioner

21. When a problem exists with a linear positioner circuit, the first thing you would do is to:
Change the servo valve
Change the Temposonic transducer
Increase the pressure
Drive the servo valve with a battery box

22. What is the most reliable indication of a faulty variable displacement hydraulic pump?
Low system pressure
Low oil temperature
Excessive case drain flow
A steady high-pitched whining sound

23. What determines the speed of a hydraulic cylinder or a motor?
System pressure
Amount of oil flow
Size of the load
Directional valve center position

24. Which of the following applications would require a non bypassing type filter?
Return line filter
Downstream of a fixed displacement pump
Upstream of a servo valve
In a separate filtering and cooling circuit

25. To prevent seal leakage, the case drain line of a hydraulic motor should:
Be connected to a system return line
Be plugged
Run directly back to the tank
None of the above

Score =