A1 Post Test Quiz

Press-fit piston pins are installed with about: 0.003 inch of interference 0.001 inch of clearance 0.002 inch of clearance 0.001 inch of interference

0.001 inch of interference

The specific gravity of a fully charged battery with an electrolyte temperature of 80'b0F will be about: 1.265 1.245 1.225 1.285

1.265

Valve margin must be at least: 1/64 inch 1/32 inch 1/16 inch 1/8 inch

1/32 inch

If the manufacturer specifies 15 to 21 in-Hg of manifold vacuum at sea level, what would be the acceptable range when testing at a 5000 foot elevation? 14 to 20 15 to 21 20 to 26 10 to 16

10 to 16

A typical electronic multi-port injection system operates at a system pressure of about: 35 psi 45 psi 25 psi Over 50 psi

35 psi

The preferred rate for charging an automotive battery is: 5 to 15 amps 15 to 25 amps Less than 20 amps Less than 5 amps

5 to 15 amps

A thermometer, timing light, and tachometer can be used to check the operation of: A fan clutch The cooling system The thermostat An electric fan

A fan clutch

Which of the following tests is NOT used to check the operation of an intake air preheat system? Thermostatic bulb test Temperature sensor test A manifold vacuum test Vacuum diaphragm test

A manifold vacuum test

With the engine running, an engine thump at normal temperature can mean: A loose drive belt A worn water pump A poor pressure cap seal A restriction in the water jacket

A restriction in the water jacket

A Hall-Effect switch on a computer-controlled engine triggers spark plug firing through the use of: A light-emitting diode and a reluctor plate A semiconductor and a permanent magnet A pick-up coil and a trigger wheel A magnetic pulse generator and an armature

A semiconductor and a permanent magnet

Insufficient system pressure in a port fuel-injection system can be caused by all of the following EXCEPT : A defective fuel-pressure regulator A sticking fuel pump check valve A clogged fuel filter A faulty fuel accumulator

A sticking fuel pump check valve

Internal cracks on a cast-iron cylinder head can be located by which of the following methods? Magnetic particle testing Pressure testing Dye penetrant testing All of the above

All of the above

A compression test was performed on a four cylinder engine with the following results: cylinder #1 = 138 psi, cylinder #2 = 127 psi, cylinder #3 = 115 psi, cylinder # 4 = 135 psi. Technician A says low compression in cylinders 2 and 3 indicates that the cylinder head gasket is leaking between these two cylinders. Technician B says the compression test is not conclusive enough to determine the problem. Uneven readings may be caused by burnt, sticking, or improperly adjusted valves or carbon deposits on the valve faces. Who is right? A only B only Both A and B Neither A nor B

B only

Technician A says the close wound end of a variable-pitch valve spring should be installed up, with the tight coils at the tip end of the valve. Technician B says the close wound end of a variable-pitch valve spring should be installed down, with the tight coils at the spring seat of the cylinder head. Who is right? A only B only Both A and B Neither A nor B

B only

Camshaft lift is the difference between: Camshaft runout and base circle diameter Journal diameter and lobe height Base circle Base circle diameter and lobe height

Base circle diameter and lobe height

f0fs24 cf0 Connecting rods are marked: Before removal After removal On the bottom of the cap With a scribe

Before removal

A cylinder bore measures 3.067 inch below ring travel at the bottom and 3.077 below the ridge at the top. The standard factory bore is 3.065. What would be the proper repair? Bore and hone the cylinder to 3.097 inch and install 0.030 inch oversize pistons with new rings Bore and hone the cylinder to 3.075 inch and install knurled pistons with new rings Deglaze the cylinder walls and install the old pistons with new cast-iron rings Bore and hone the cylinder to 3.095 inch and install 0.030-inch oversized pistons with new rings

Bore and hone the cylinder to 3.095 inch and install 0.030-inch oversized pistons with new rings

Technician A says a full-floating wrist pin should be checked for clearance fit. Technician B says a press-fit wrist pin should be checked for interference fit. Who is right? A only B only Both A and B Neither A nor B

Both A and B

Install rods and pistons: Clean and dry By pushing gently with a wooden hammer handle With rod caps reversed By tapping with a ball peen hammer

By pushing gently with a wooden hammer handle

Which of the following operations is NOT required when replacing a cylinder head gasket? Checking for leakage Checking for squareness Checking for warpage Cleaning the bolt holes

Checking for squareness

Black exhaust smoke from a turbocharged engine can indicate: Coolant leakage into the cylinders Leaking oil seals in the turbo Clogged intake air filter High boost pressure

Clogged intake air filter

Cylinder head gasket failure may be due to all of the following EXCEPT : Vacuum leaks Compression leaks Oil leaks Coolant leaks

Compression leaks

Failure to remove the cylinder ridge before removing the piston and connecting rod assemblies from the engine block can result in: Scored cylinder walls Bent connecting rods Broken piston skirts Damaged piston ring lands

Damaged piston ring lands

Low system pressure on an engine with electronic fuel injection can be caused by all of the following EXCEPT : Clogged fuel filter Faulty fuel pressure regulator Defective fuel pump check valve Defective fuel pump

Defective fuel pump check valve

Which of the following tools will give the most accurate measurements when calculating valve guide wear? Split-ball gauge Inside micrometer Dial indicator Dial bore gauge

Dial bore gauge

Most turbocharger failures are caused by: Excessive high-speed operation Dirt and contamination Exhaust temperatures too high Operation with leaded gasoline

Dirt and contamination

To check base timing on a latemodel computer-controlled engine, it may be necessary to: Disconnect the throttle position sensor Disable computer controlled timing Bypass the idle air control valve Disconnect the oxygen sensor

Disable computer controlled timing

Which of the following circuits is NOT part of the cranking system? Ignition switch Engine speed sensor Starter relay Battery

Engine speed sensor

Which of the following may be a cause of low oil pressure? Worn piston rings Excessive valve guide clearance Excessive main bearing clearance Stretched timing chain

Excessive main bearing clearance

A fluorescent dye test is used to check for: External coolant leaks Combustion leaking into the coolant Coolant leaking into the crankcase Internal oil leaks

External coolant leaks

Valve springs are bench tested for all of the following EXCEPT : Installed height Tension pressure Squareness Free height

Installed height

Low readings on a starter motor cranking voltage test can be caused by all of the following EXCEPT : Low starter pinion speed Weak battery High circuit resistance Internal starter problem

Internal starter problem

Which of the following methods is NOT used for detecting cracks in a cast-iron cylinder head? Dye penetrant testing Pressure testing Magnetic particle testing Leak-down testing

Leak-down testing

To check the boost pressure of a turbocharger, a pressure gauge is installed: In the intake air plenum On the compressor side of the turbocharger At the wastegate port of the turbocharger On the turbine side of the turbocharger

On the compressor side of the turbocharger

The thermostatically controlled air cleaner should: Open the hot air passage during warmup Provide hot air at all times Provide cool air at all times Close the hot air passage during warmup

Open the hot air passage during warmup

During an oil pressure test, low oil pressure is noted only at low engine speeds, and there are no abnormal engine noises. These findings may indicate: Faulty hydraulic valve lifters Pressure-oiled rocker arm shaft assembly wear Badly worn engine bearings An open oil pump pressure relief valve

Pressure-oiled rocker arm shaft assembly wear

In a cylinder compression test, if the compression is low on the first stroke and increases on following strokes but never reaches specifications, it probably means: Excessive carbon build-up Rings may be worn or valves may be sticking Cylinder compression is okay Head gasket may be leaking

Rings may be worn or valves may be sticking

Which of the following is the proper procedure for performing a cylinder balance test? Run the engine at idle, short the spark plugs one at a time, and note any rpm drop Run the engine at 1500 rpm, short the spark plugs two at a time, and note any rpm drop Run the engine at idle speed, shorting all but two spark plugs, and note any rpm drop Run the engine at 1500 rpm, short the spark plugs one at a time, and note any rpm drop

Run the engine at 1500 rpm, short the spark plugs one at a time, and note any rpm drop

After machining, the cylinder walls are cleaned with: Soap and Water A glaze breaker Solvent A hot tank

Soap and Water

Checking manifold vacuum with a gauge will reveal all of the following problems EXCEPT : Worn valve guides Sticking hydraulic lifter Exhaust restriction Worn piston rings

Sticking hydraulic lifter

A connecting-rod alignment fixture is used to check all of the following EXCEPT: Twist Offset Stretch Bend

Stretch

A pressure tester can be used to: Test the coolant Test for exhaust leaks into the cooling system Test thermostats Test radiators, pressure caps, and hoses

Test radiators, pressure caps, and hoses

Which of the following items must be removed in order to remove hydraulic lifters from an OHV engine? The cylinder head The pushrod The camshaft The rocker arm

The pushrod

When assembling the connecting rod onto a piston: The piston notch is always to the rear of the engine The rod can be installed in one direction only The rod can be installed in either direction The piston pin must be installed in the connecting rod first

The rod can be installed in one direction only

In a high mileage engine, cylinder wear is normally the greatest at the: Top of the cylinder measured parallel to the crankshaft Top of the cylinder measured at right angles to the crankshaft Bottom of the cylinder measured parallel to the crankshaft Bottom of the cylinder measured at right angles to the crankshaft

Top of the cylinder measured at right angles to the crankshaft

To bleed off excess boost pressure during idle and low speed operation, most supercharger engines use a(n): Pressure-controlled wastegate Pop-off valve Electric cut-out switch Vacuum-operated bypass valve

Vacuum-operated bypass valve

Starter circuit resistance tests are performed with a(n): Oscilloscope Voltmeter Ohmmeter Ammeter

Voltmeter

During a manifold vacuum test a rapid needle vibration on acceleration is noticed. This can be caused by: A restricted exhaust system Worn valve guides A rich air-fuel ratio Weak valve springs

Weak valve springs

A cylinder compression test reveals fairly even compression, but lower than specification. A second wet test results in higher readings on all cylinders. These results indicate: Poor valve seating Worn valve guides Worn piston rings Leaking head gasket

Worn piston rings

The needle of a vacuum gauge rapidly vibrates between 14 and 18 in-Hg with the engine running at idle. As engine speed increases, the gauge stops vibrating and stabilizes. These readings are most likely caused by: Weak piston rings Incorrect fuel mixture Worn valve guides Weak valve springs

Worn valve guides