Automotive Technology Chapters 27 & 28

In checking a journal bearing clearances in a turbocharger, Technician A says the dial indicator is positioned so that it can touch the main turbocharger shaft between the bearings. Technician B says move the shaft up and down from either the compressor or turbine end to check bearings. Who is correct?

• A only

• B only

• Both A and B

• Neither A nor B

An engine is lacking power, Technician A says it could be caused by a dirty air cleaner. Technician B says it could be caused by a restriction in the air intake system. Who is correct?

• A only

• B only

• Both A and B

• Neither A nor B

A dirty air filter can cause the air/fuel ratio to be _____.

• Rich

• Lean

• Constant

• Absolute

Technician A says the heat riser is used to allow exhaust gasses to pass more quickly through the exhaust manifold. Technician B says the heat riser is used to aid in vaporization of fuel. Who is correct?

• A only

• B only

• Both A and B

• Neither A nor B

Manifolds are classified as wet if _____.

• the ambient atmosphere is humid

• moisture has entered the fuel lines

• coolant passages are cast into the manifold

• moisture from the road surface is entering the engine

_____ is the measure of the amount of air pressure, above atmospheric, that a turbocharger can deliver.

• Vacuum

• Boost

• Horsepower

• Torque

Technician A says intake manifold design can increase horsepower. Technician B says horsepower is not affected by air flow. Who is correct?

• A only

• B only

• Both A and B

• Neither A nor B

An engine with a turbocharger needs to be inspected. Technician A says the radial clearances should be checked on the main shaft. Technician B says the axial clearances should be checked on the main shaft. Who is correct?

• A only

• B only

• Both A and B

• Neither A nor B

Technician A says the wastegate is normally open to allow exhaust gasses to by-pass the turbine. Technician B says the wastegate is normally closed to allow exhaust gasses to turn the turbine. Who is correct?

• A only

• B only

• Both A and B

• Neither A nor B

A resonator is used to _____.

• increase air flow

• reduce noise

• sense air/fuel ratio

• heat up the catalytic converter