ENGINE REPAIR MICHIGAN MECHANIC STUDY GUIDE – Questions And Solutions
Which of the following is true about adjusting valve tappet clearance a. The valve tappet clearence on a high mileage egine should be adjusted tighter than specifications for a newly rebuilt engine.
B. Valve tappet clearance should be adjusted at tdc at the end of the compression stroke. (correct answer )
C. Valve tappet clearance should be adjusted at bdc at the end of the exhaust stroke.
D. None of the above. (not correct answer )
The hydraulic lifters are noisy at highway speeds but quiet at low speeds. What should you do first as you diagnose this problem? a. Check lifter leakdown rate.
B. Check crankcase oil level. (correct answer )
C. Check lifter clearance hot. (not correct answer )
D. Check lifter clearance cold.
The valve timing on most engines is controlled by: a. An on board computer. (not correct answer )
B. A centrifugal advance unit.
C. A vacuum advance unit
D. A belt, chain or gear drive. (correct answer )
The bearing inserts below have been plastigaged. What can you determine about these pictures? a. Both bearing journals are out of round. (not correct answer )
B. Insert "b" has more clearance.
C. Insert"a" has more clearance.
D. Both bearings have excessive taper.
The compression test has showed that the middle two cylinders on one side of
a v-8 engine had readings of 50 psi. The other cylinders had readings between 135 psi and 140 psi. What is the likely cause of this condition? a. A burned
exhaust valve
B. A blown intake manifold gasket.
C. A blown head gasket. (correct answer ) D. A burned intake valve. (not correct answer )
Excessively worn valve guides: a. May be replaced if removable.
B. May be reamed to oversize.
C. May cause oil consumption.
D. All of the above. (correct answer )
Intake valve deposits, as shown below: a. Will not affect engine performance.
B. Can reduce volumetric efficiency and affect high rpm performance.
C. Can cause driveability problems during cold engine operation.
D. Both b and c. (correct answer )
What is being checked on the valve spring in the illustration below? a. Installed height (correct answer )
B. Squareness
C. Coil taper
D. Tension (not correct answer )
You are using a vacuum gauge connected to the intake manifold. Which of the following is true? a. When the engine is rapidly accelerated, the needle will rise to a high reading. (possible correct answer )
B. When the throtle is released suddenly from 2500 rpm, the needle will snap to a higher than normal reading for an instant.
C. A "normal" gauge reading at idle would be 7-10 inches.
D. All of the above. (not correct answer )
What are the minimum and maximum measurements of a shaft given 2.125 plus or minius .015? a. 2.062-2.250 (not correct answer )
B. 1.975-2.275
C. 2.110-2.140 (correct answer )
D. 2.124-2.126
The mechanic has determined that no fuel squirts into the carburetot when the throttle is opened quickly. What could be caused by: a. Disconnected linkage.
B. A hardened accelerator pump plunger.
C. A plugged pump nozzle.
D. All of the above. (correct answer )
Which of the following is true about adjusting valve tappet clearance a. The valve tappet clearence on a high mileage egine should be adjusted tighter than specifications for a newly rebuilt engine.
B. Valve tappet clearance should be adjusted at tdc at the end of the compression stroke. (correct answer )
C. Valve tappet clearance should be adjusted at bdc at the end of the exhaust stroke.
D. None of the above. (not correct answer )
The hydraulic lifters are noisy at highway speeds but quiet at low speeds. What should you do first as you diagnose this problem? a. Check lifter leakdown rate.
B. Check crankcase oil level. (correct answer )
C. Check lifter clearance hot. (not correct answer )
D. Check lifter clearance cold.
The valve timing on most engines is controlled by: a. An on board computer. (not correct answer )
B. A centrifugal advance unit.
C. A vacuum advance unit
D. A belt, chain or gear drive. (correct answer )
The bearing inserts below have been plastigaged. What can you determine about these pictures? a. Both bearing journals are out of round. (not correct answer )
B. Insert "b" has more clearance.
C. Insert"a" has more clearance.
D. Both bearings have excessive taper.
The compression test has showed that the middle two cylinders on one side of
a v-8 engine had readings of 50 psi. The other cylinders had readings between 135 psi and 140 psi. What is the likely cause of this condition? a. A burned
exhaust valve
B. A blown intake manifold gasket.
C. A blown head gasket. (correct answer ) D. A burned intake valve. (not correct answer )
Excessively worn valve guides: a. May be replaced if removable.
B. May be reamed to oversize.
C. May cause oil consumption.
D. All of the above. (correct answer )
Intake valve deposits, as shown below: a. Will not affect engine performance.
B. Can reduce volumetric efficiency and affect high rpm performance.
C. Can cause driveability problems during cold engine operation.
D. Both b and c. (correct answer )
What is being checked on the valve spring in the illustration below? a. Installed height (correct answer )
B. Squareness
C. Coil taper
D. Tension (not correct answer )
You are using a vacuum gauge connected to the intake manifold. Which of the following is true? a. When the engine is rapidly accelerated, the needle will rise to a high reading. (possible correct answer )
B. When the throtle is released suddenly from 2500 rpm, the needle will snap to a higher than normal reading for an instant.
C. A "normal" gauge reading at idle would be 7-10 inches.
D. All of the above. (not correct answer )
What are the minimum and maximum measurements of a shaft given 2.125 plus or minius .015? a. 2.062-2.250 (not correct answer )
B. 1.975-2.275
C. 2.110-2.140 (correct answer )
D. 2.124-2.126
The mechanic has determined that no fuel squirts into the carburetot when the throttle is opened quickly. What could be caused by: a. Disconnected linkage.
B. A hardened accelerator pump plunger.
C. A plugged pump nozzle.
D. All of the above. (correct answer )
