TERRY FOX AUTOMOTIVE CH. 48 ENGINE MECHANICAL PROBLEMS TEST WHEN YOU ARE DONE THIS TEST GUESS WHAT YOU THINK YOU WILL RECEIVE FOR A MARK BELOW. IF YOU ARE WITHIN 2 MARKS YOU WILL RECEIVE 2 BONUS MARKS. I THINK I WILL RECEIVE /30
Chapter 48 Engine Mechanical Problems Test Student Name: Date: Multiple Choice: (one mark each) 1. With a gasoline engine, blue-grey smoke indicates: a. Rich fuel mixture b. Coolant leakage into combustion chambers c. Oil leakage into combustion chambers d. Lean fuel mixture 2. Low cylinder compression cannot be cause by: a. Worn camshaft bearings b. Blown head gasket c. Burned valve d. Worn piston rings 3. An automobile is brought into the shop. A compression test on the engine indicates low compression stroke pressure in all the engine s cylinders. Technician A says a complete engine overhaul is required to repair this problem. Technician B says before overhauling the engine you should check for other mechanical problems that would affect engine compression. Who is right? 4. Technician A says when inspecting an engine for mechanical troubles, you should look for engine oil leaks. Technician B says when inspecting an engine for mechanical troubles, you should look for vacuum leaks. Who is right? 5. Technician A says a leaking gasket is a common engine mechanical problem. Technician B says a burned valve is a common engine mechanical problem. Who is right? 6. Which of the following is a common cause of engine mechanical problems? a. Engine overheating b. Lack of periodic maintenance c. High engine mileage d. All of the above
7. The oil in an automotive engine has a white milky appearance. Technician A says this indicates engine coolant is probably leaking into the engine. Technician B says this indicates transmission fluid is probably leaking into the engine. Who is right? 8. An engine is brought into the shop with oil fouled spark plugs. Technician A says this problem is probably caused by an ignition system malfunction. Technician B says this problem is probably caused by internal oil leakage into the engine s combustion chambers. Who is right? 9. Oil is present in an automobile engine s coolant. Technician A says this problem is normally the result of worn valve seals. Technician B says this problem is usually caused by a leak in the radiator transmission oil cooler. Who is right? 10. An automobile s engine is producing crankcase blowby. Technician A says the solution to this problem is simple valve adjustment. Technician B says the solution to this problem normally requires extensive engine repair. Who is right? 11. Technician A says engine vacuum leaks are normally loudest at highway speeds. Technician B says engine vacuum leaks are normally loudest during engine cranking. Who is right? 12. Blue-grey smoke is coming out of an automobile s exhaust. Technician A says this condition normally indicates water in the engine s oil supply. Technician B says this condition normally indicates internal engine mechanical problems. Who is right?
13. Black smoke is coming out of a gasoline engine s tailpipe. Technician A says this normally indicates an engine mechanical problem. Technician B says this condition normally indicates a fuel system problem. Who is right? 14. White exhaust smoke is coming out of a gasoline engine s tailpipe. Technician A says white exhaust smoke may indicate an internal coolant leak into the engine s cylinders. Technician B says white exhaust smoke may be due to water condensation on a cool day. Who is right? 15. An automobile equipped with a diesel engine is brought into the shop. The customer says there is blue smoke coming out of the engine s exhaust. Technician A says this problem may be due to worn engine cylinders. Technician B says this problem may be due to worn valve seals. Who is right? 16. Technician A says a gasoline engine compression gauge can be used to perform a compression test on a diesel engine. Technician B says a gasoline engine compression gauge should not be used to perform a diesel engine compression test. Who is right? 17. Diesel engine compression readings should average approximately: a. 125-175psi b. 180-200psi c. 150-175psi d. 275-400psi 18. Valve train problems can cause all of the following except: a. Oil consumption b. Rough idle c. Crankshaft damage d. Engine missing
19. Technician A says that leaking valve stem seals will cause the engine to emit blue smoke after initial starting. Technician B says that the cylinder head must generally be removed to replace the valve stem seals. Who is right? 20. Technician A says that valve float can be caused by hydraulic lifter problems. Technician B says that valve float can be the result of weak valve springs. Who is right? 21. Technician a says that worn rocker arms can upset valve clearance. Technician B says that worn rocker arms have little effect on engine performance. Who is right? 22. All of the following are caused by blown head gasket except: a. Overheating b. Head damage c. Excess valve clearance d. Coolant leaks 23. Technician A says that a leaking intake manifold gasket can cause a vacuum leak. Technician B says that a high vacuum gauge reading indicates a blown head gasket. Who is right? 24. Technician A says that piston slap is generally loudest when the engine is warm. Technician B says that piston slap is caused by excessive piston skirt wear. Who is right 25. Technician A says that rod knock is a light, regular rapping noise that occurs when the engine is accelerating. Technician B says that rod knock is loudest when the engine is cold. Who is right?
26. Technician A says that main bearing knock is duller in pitch than rod bearing knock. Technician B says that main bearing wear will significantly reduce oil pressure. Who is right? 27. Excess crankshaft end play is caused by: a. Worn rod journals b. Worn crank throws c. Worn thrust bearings d. Worn connecting rods True or False: (one mark each) 28. True or False - A section of vacuum hose can be used to find engine vacuum leaks. 29. True or False If a cylinders compression increases when doing a wet compression test after a dry compression test it means that the compression rings are faulty. 30. True or False A leaking intake manifold gasket can cause a vacuum leak, with a resulting rough idle. TOTAL MARK /30 BONUS /2 FINAL MARK /30