SOS Mechanic Certificate -Engine
Repair
WHICH OF THE FOLLOWING IS TRUE ABOUT ADJUSTING VALVE TAPPET
CLEARANCE - Answer- VALVE TAPPET CLEARANCE SHOULD BE ADJUSTED
AT TDC AT THE END OF THE COMPRESSION STROKE.
THE HYDRAULIC LIFTERS ARE NOISY AT HIGHWAY SPEEDS BUT QUIET AT
LOW SPEEDS. WHAT SHOULD YOU DO FIRST AS YOU DIAGNOSE THIS
PROBLEM? - Answer- CHECK CRANKCASE OIL LEVEL.
THE VALVE TIMING ON MOST ENGINES IS CONTROLLED BY: - Answer- A
BELT, CHAIN OR GEAR DRIVE
THE BEARING INSERTS BELOW HAVE BEEN PLASTIGAGED. WHAT CAN YOU
DETERMINE ABOUT THESE PICTURES? - Answer- INSERT"A" HAS MORE
CLEARANCE.
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? - Answer- A BLOWN HEAD GASKET.
EXCESSIVELY WORN VALVE GUIDES: - Answer- ALL OF THE ABOVE.
INTAKE VALVE DEPOSITS, AS SHOWN BELOW: - Answer- BOTH B AND C
WHAT IS BEING CHECKED ON THE VALVE SPRING IN THE ILLUSTRATION
BELOW? - Answer- INSTALLED HEIGHT
YOU ARE USING A VACUUM GAUGE CONNECTED TO THE INTAKE MANIFOLD.
WHICH OF THE FOLLOWING IS TRUE? - Answer- WHEN THE ENGINE IS
RAPIDLY ACCELERATED, THE NEEDLE WILL RISE TO A HIGH READING.
WHAT ARE THE MINIMUM AND MAXIMUM MEASUREMENTS OF A SHAFT
GIVEN 2.125 PLUS OR MINIUS .015? - Answer- 2.062-2.250
THE MECHANIC HAS DETERMINED THAT NO FUEL SQUIRTS INTO THE
CARBURETOT WHEN THE THROTTLE IS OPENED QUICKLY. WHAT COULD BE
CAUSED BY: - Answer- ALL OF THE ABOVE.
A WARM ENGINE HAS LOW OIL PRESSURE. THE MOST LIKELY CAUSE OF
THE LOW OIL PRESSURE IS: - Answer- LEAKY MAIN BEARING SEALS
Repair
WHICH OF THE FOLLOWING IS TRUE ABOUT ADJUSTING VALVE TAPPET
CLEARANCE - Answer- VALVE TAPPET CLEARANCE SHOULD BE ADJUSTED
AT TDC AT THE END OF THE COMPRESSION STROKE.
THE HYDRAULIC LIFTERS ARE NOISY AT HIGHWAY SPEEDS BUT QUIET AT
LOW SPEEDS. WHAT SHOULD YOU DO FIRST AS YOU DIAGNOSE THIS
PROBLEM? - Answer- CHECK CRANKCASE OIL LEVEL.
THE VALVE TIMING ON MOST ENGINES IS CONTROLLED BY: - Answer- A
BELT, CHAIN OR GEAR DRIVE
THE BEARING INSERTS BELOW HAVE BEEN PLASTIGAGED. WHAT CAN YOU
DETERMINE ABOUT THESE PICTURES? - Answer- INSERT"A" HAS MORE
CLEARANCE.
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? - Answer- A BLOWN HEAD GASKET.
EXCESSIVELY WORN VALVE GUIDES: - Answer- ALL OF THE ABOVE.
INTAKE VALVE DEPOSITS, AS SHOWN BELOW: - Answer- BOTH B AND C
WHAT IS BEING CHECKED ON THE VALVE SPRING IN THE ILLUSTRATION
BELOW? - Answer- INSTALLED HEIGHT
YOU ARE USING A VACUUM GAUGE CONNECTED TO THE INTAKE MANIFOLD.
WHICH OF THE FOLLOWING IS TRUE? - Answer- WHEN THE ENGINE IS
RAPIDLY ACCELERATED, THE NEEDLE WILL RISE TO A HIGH READING.
WHAT ARE THE MINIMUM AND MAXIMUM MEASUREMENTS OF A SHAFT
GIVEN 2.125 PLUS OR MINIUS .015? - Answer- 2.062-2.250
THE MECHANIC HAS DETERMINED THAT NO FUEL SQUIRTS INTO THE
CARBURETOT WHEN THE THROTTLE IS OPENED QUICKLY. WHAT COULD BE
CAUSED BY: - Answer- ALL OF THE ABOVE.
A WARM ENGINE HAS LOW OIL PRESSURE. THE MOST LIKELY CAUSE OF
THE LOW OIL PRESSURE IS: - Answer- LEAKY MAIN BEARING SEALS
