ASE A1 Engine Repair Practice Test

66. An engine is leaking oil past several oil seals. Technician A says a stuck closed PCV valve would cause this problem. Technician B says a clogged crankcase breather tube would result in this condition. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

66.

Answer A is wrong. A stuck closed PCV valve results in excessive crankcase pressure and oil forced past seals and gaskets.

Answer B is wrong. Engine breather hoses and filters get kinked or clogged, restricting flow and allowing blowby gases to build in the crankcase.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Both technicians are correct.

67. Technician A says that a rich air-fuel ratio can result in excessive carbon buildup on the engine's valves and pistons. Technician B says coolant entering the combustion chamber results in excessive carbon buildup in the cylinder and piston crowns. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

67.

Answer A is correct. Poor fuel and rich air-fuel ratios result in excessive carbon buildup on the valves and piston crowns. The intake valves in gasoline direct injection engines do not benefit from fuel cleaning the intake port and valve.

Answer B is wrong. Coolant entering the combustion chamber will typically vaporize, soften and then "wash" the carbon off the piston crown.

Answer C is wrong. Technician A is correct

Answer D is wrong. Technician A is correct

68. Technician A says a blown head gasket results in coolant entering the combustion chamber. Technician B says a blown head gasket could result in contaminated milky brown engine oil. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

68.

Answer A is wrong. Coolant entering the combustion chamber will vaporize, resulting in white-colored exhaust smoke.

Answer B is wrong. Coolant enters the crankcase through a blown head gasket or leaking intake manifold jacket and mixes with the oil. As a result, the oil turns milky brown and can be seen on the dipstick and accumulate around the oil and radiator fill neck.

Answer C is correct. Both Technicians are correct.

Answer D is wrong. Both Technicians are correct.

69. Technician A says to use a feeler gauge to measure the top compression piston ring end gap. Technician B says if the piston ring end gap is too small, the ends may touch, resulting in scuffing and binding. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

69.

Answer A is wrong. Use a feeler gauge to measure the top compression piston ring end gap.

Answer B is wrong. Too much piston ring end gap results in compression leaks and blowby, and too little gap results in the ends touching, causing scuffing, binding, and possible catastrophic engine failure.

Answer C is correct. Both technicians are correct.

Answer D is wrong. Both technicians are correct.

70. Technician A says when replacing a cylinder head to reuse the torque to yield bolts as long as they are cleaned and oiled before they are reinstalled and torqued. Technician B says after removal, a torque to yield bolt always returns to its original length. Who is correct?

  • A. Technician A
  • B. Technician B
  • C. Both A and B
  • D. Neither A or B

70.

Answer A is wrong. With a standard bolt, a technician could torque the bolt to its yield point, and it would return to its original form and length when removed. It has elasticity; it can stretch and then return to its original form.

Answer B is wrong. Cleaning a bolt that has stretched does not restore it to its original length.

Answer C is wrong. This answer could be correct if the TTY bolt passes all of the manufacturer's required specifications. Be careful when clamping cylinder heads with these bolts.

Answer D is correct. Neither technician is correct. Due to the nature of their design, torque to yield bolts or stretch bolts should not always be reused.

ASE A1 Engine Repair Quiz
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