Which of the following could cause the brakes on a truck to wear too fast?
A. glazed drums
B. wrong linings installed
C. Low air pressure
D. governor cut out pressure Correct Ans - B. wrong linings installed
which of the following could cause one brake on a truck to wear faster than
the others?
A. mismatched service brake chambers
B. mismatched parking chambers
C. low air pressure in service tanks
D. governor cut out too low Correct Ans - A. mismatched service
chambers
what force is used to apply the foundation brake wheel cylinders?
A. hydraulic from the steering reservoir
B. mechanical
C. electrical
D. hydraulic from the master cylinder Correct Ans - D.
there's an audible air leak from under the dash when the foot valve is applied.
technician A says the double check valve may be faulty. Tech B says the single
check valve may be faulty. who's correct? Correct Ans - Tech A only
on a straight truck equipped with air brake, the secondary tank pressure
gauge falls to zero when the wet tank air is drained. Tech A says the one way
check valve is faulty, Tech B says the foot valve may be faulty. Who's correct?
Correct Ans - Tech A only. one way check valve protects secondary tank
A loose wheel bearing adjustment can cause a faulty wheel speed sensor and a
wheel speed sensor code Correct Ans -
Air dryer purges too often. Tech A says the air dryer delivery check Valve may
be faulty. Tech B says a leaking wet tank could be the cause. Who's correct?
Correct Ans - C. Both Techs.
The safety valve releases on the air tank. Which is the most likely cause?
, A. plugged line from the supply tank to governor.
B. faulty tractor protection valve
C. stuck spitter on the air drier
D. faulty secondary tank Correct Ans - A. if the line was plugged, the
governor would not unload the compressor
A truck with hydraulic disc/drum brakes has a high firm pedal with poor
stopping. what could be the cause? Correct Ans - The brake linings are
glazed! Glazed brake linings will allow the pedal to feel high and firm with no
stopping power
Air builds on a truck in 1.5 minutes. The specs. manual says it should take 3.5
min. Tech A says the air tanks could have water build up. Tech B says the air
tanks could have oil built up. Whos correct? Correct Ans - C. Both
technicians. Any Build up reduces volume for stored air
Brake fluid is leaking from the rear of a master cylinder on a hydro boost
brake system. What is the likely cause? Correct Ans - Primary seal
leaking.
Air pressure build up time on a gear driven compressor is greater than
specifications. What is the cause?
A. a slipping drive
B. a leaking service relay
C. leaking primary tank
D. leaking parking brake chamber Correct Ans - C. A leaking primary air
tank causes extended air build up time
air leaks from the left front modulator valve during service operation. There
are no ABS codes. What is the cause? Correct Ans - Modulator Valve seat
air is leaking from a quick release valve mounted on the front axle during
service application. What is the cause? Correct Ans - Quick release
The three ports on a governor are: Correct Ans - Reservoir, Unloaded
and exhaust
Pressure valves open at : Correct Ans - 150PSI