HEAVY TRUCK BRAKES MICHIGAN MECHANIC PRACTICE QUESTIONS WITH 100% CORRECT ANSWERS

HEAVY TRUCK BRAKES
MICHIGAN
MECHANIC PRACTICE
QUESTIONS WITH 100%
CORRECT ANSWERS

1. TOO MUCH EFFORT IS REQUIRED ON THE BRAKE PEDAL TO STOP A TRUCK WITH
A VACUUM BOOSTER. WHAT IS THE LIKELY CAUSE OF THIS PROBLEM? A.
SEIZED AUTOMATIC ADJUSTERS.
B. GLAZED LININGS
C. A DEFECTIVE MODULATOR VALVE. (CORRECT AWNSER)
D. VERY HIGH ENGINE VACUUM.


2. WITH THE VALVE PICTURED BELOW, THE OPERATOR CAN: A. APPLY THE
TRACTOR BRAKES BY SPRING PRESSURE. B. APPLY THE TRAILER BRAKES BY AIR
PRESSURE.
C. ENGAGE OR DISENGAGE THE PARKING BRAKES. (CORRECT AWNSER)


D. APPLY THE TRAILER BRAKES BY SPRING PRESSURE.


3. IT IS FOUND THAT THE RUBBER DIAPHRAGM IN A MASTER CYLINDER COVER IS
SWOLLEN TO NEARLY DOUBLE IN SIZE. THIS COULD BE CAUSED BY: A.

, CONTAMINATION OF THE BRAKE FLUID WITH ENGINE OIL. B. ACCIDENTAL
MIXING WITH SILICONE BRAKE FLUID.
C. MOISTURE IN THE BRAKE FLUID.
D. ALL OF THE ABOVE. (CORRECT AWNSER)


4. WITH THE ENGINE STOPPED, A MECHANIC HOLDS THE POWER BRAKE PEDAL IN
THE DEPRESSED POSITION. THE MECHANIC THE STARTS THE ENGINE WITH THE
PEDAL STILL DEPRESSED. THE PEDAL SINKS SLIGHTLY. WHAT DOES THIS
INDICATE? A. THE BRAKE BOOSTER IS SATISFACTORY. (CORRECT AWNSER)
B. A LEAKING CHECK VALVE.
C. A TORN DIAPHRAGM.
D. A DEFECTIVE CONTROL VALVE ASSEMBLY.


5. A MECHANIC FINDS GEAR LUBE INSIDE BOTH BRAKE DRUMS ON A DRIVING AXLE.
WHAT IS THE MOST LIKELY CAUSE OF THIS PROBLEM? A. A BAD PINION
SEAL.
B. A PLUGGED AXLE VENT. (CORRECT AWNSER)
C. A BAD WHEEL BEARING.
D. A BAD DIFFERENTIAL CASE SEAL.


6. WHEN COMPLETING A BRAKE RELINE, WHAT BRAKE LINKAGE SHOULD THE
MECHANIC LUBRICATE? A. THE ANCHOR PINS.
B. THE CAMSHAFTS.
C. THE SLACK ADJUSTER.
D. ALL OF THE ABOVE. (CORRECT AWNSER)




7. IN THE SYSTEM SHOWN BELOW, A QUICK RELEASE VALVE WOULD BE NEEDED
AT: A. POINT E.