Advanced Auto Tech. ASE A 1 Test Preparation Engine Lower End Theory & Service

Transcription

1 Advanced Auto Tech ASE A 1 Test Preparation Engine Lower End Theory & Service

2 To make work easier, one of the first steps often done before engine removal is to clean & degrease the engine compartment. True or False

3 An engine sling should be held to the block or heads with bolts that thread into the block at least 1 ½ times their diameter. True or False

4 Wear mated parts should be marked, labeled & kept organized to assist with failure analysis. True or False

5 Rod bolt covers are used to protect the highly polished connecting rod journal (crankpin) during both removal & installation of pistons & connecting rod assemblies. True or False

6 Plastigage is a consumable measuring tool used to check precision insert bearing clearances. The wider it s crushed, the tighter the bearing oil clearance is. True or False

7 Magnetic crack detection on ferrous parts is often referred to by its trade name Magnafluxing there is also a dye method for use on non ferrous metal (aluminum & magnesium) components. True or False

8 Low engine oil pressure can be an indicator of main bearings with insufficient oil clearance more often than oil pump issues. True or False

9 Low engine oil pressure can be an indicator of main bearings with insufficient oil clearance more often than oil pump issues.

10 Camshafts always turn at twice the crankshaft RPM. 360º of cam rotation & 720º of crank rotation in a 4 stroke cycle. True or False

11 To determine piston ring groove wear, side clearance should be measured using new piston rings. True or False

12 Piston ring end gap is measured with the old rings to determine their wear, but end gap should be checked on new rings to assure they are not too tight and would score the cylinder wall. True or False

13 Wrist pins are offset toward the major thrust surface of the cylinder in an effort to eliminate piston slap. True or False

14 The major thrust surface of the cylinder is the one that gets the hard hit of combustion pressure. 90 to crank centerline True or False

15 The major thrust surface of the cylinder is the one that gets the hard hit of combustion pressure. 90 to crank centerline True or False

16 Following cylinder honing or deglazing, how & with what should the engine block be cleaned?

17 After block line boring, a block must be fit with bearings that are: [ ] standard size [ ] under size [ ] over size

18 After crank main journal regrinding, a block needs bearings that are: [ ] standard size [ ] under size [ ] over size

19 Which engine has push rods & rocker arms: [ ] overhead valve [ ] overhead cam [ ] rotary [ ] F head

20 Determine the displacement of a cylinder & 4 cylinder engine with Bore & a Stroke: B x B x S x.785 x # of Cyls. = Disp. Top Dead Center Bottom Dead Center

21 Determine the displacement of a cylinder & 8 cylinder engine with Bore & a Stroke: B x B x S x.785 x # of Cyls. = Disp. Top Dead Center Bottom Dead Center

22 Determine displacement of a cylinder & 4 cylinder engine with a 30 cm Bore & a 50 cm Stroke: B x B x S x.785 x # of Cyls. = Disp.

23 Determine displacement of a cylinder & 6 cylinder engine with a 25 cm Bore & a 50 cm Stroke: B x B x S x.785 x # of Cyls. = Disp.

24 What tool is used to remove or ream the cylinder ring ridge out of the top of the cylinder prior to piston removal?

25 How is compression ratio mathematically determined?

26 Which parts in an engine block control crankshaft end play? Or which parts could be worn & result in excessive end play?

27 Distance measured from TDC to BDC in the cylinder: A. Stroke B. Taper C. Out of Round D. Crank Throw

28 Loud, dull knock from the lower end of the engine block A. Rod Bearing B. Main Bearing C. Wrist Pin D. Piston Slap

29 Also known as freeze plugs A. Spark Plugs B. Core Plugs C. Pipe Plugs D. Expansion Tubes

30 Top piston ring A. Scraper or Wiper Ring B. Segmented Ring C. Oil Control Ring D. Compression Ring

31 Double knock heard at engine idle speeds A. Rod Bearing B. Main Bearing C. Wrist Pin D. Piston Slap

32 Precision insert bearing surface coating that is an alloy of: tin, copper, and antimony A. Babbit B. Assembly Lube C. Anaerobic D. RTV Aerobic

33 Connecting rod journal A. Rod Bearing B. Main Bearing C. Wrist Pin D. Crank Pin

34 Bottom piston ring A. Bauk Ring B. Blocking Ring C. Oil Control Ring D. Compression Ring

35 Determined by comparing TDC and BDC cylinder diameters A. Stroke B. Taper C. Out of Round D. Compression Ratio

36 Cylinder diameter A. Stroke B. Taper C. Out of Round D. Bore

37 Distance from the centerline of the main journal to the centerline of the rod journal on the crankshaft A. Stroke B. Taper C. Out of Round D. Crank Throw

38 Fastens the piston to the upper end of the connecting rod A. Rod Bearing B. Main Bearing C. Wrist Pin D. Crank Pin

39 Harmonic balancer used to dampen crankshaft torsional vibration A. Saddle Bore B. Bearing Saddle C. Vibration Damper D. Pilot Bearing

40 Determined by comparing bore diameters measured 90º to each other at the top of the cylinder A. Stroke B. Taper C. Out of Round D. Crank Throw

41 Engine block main bearing centerline A. Saddle Bore B. Bearing Crush C. Bearing Spread D. Bearing Clearance

42 Bearing Free Spread: The free spread is the distance between the parting lines of the half bearings in free condition. Free spread diameter will be in excess of the diameter of the housing bore. While fitment, the half bearings have to be forced into the housing, which in turn helps to firmly hold the bearings while assembly. Bearing Crush: Each half bearing is made slightly higher than exact half of the housing bore diameter. When these bearings are installed in a housing bore and the caps tightened, the parting faces mate with each other. The bearing crush creates a radial pressure and ensures proper seating of the bearing to the wall of the housing.

43 Axial movement of the crankshaft in the block, measured with a dial indicator A. Radial Runout B. Total Indicated Runout (T.I.R.) C. End Play D. Bearing Clearance

44 Right angle movement of the crankshaft while in v blocks or main bearings measured with a dial indicator A. Radial Runout B. Total Indicated Runout (T.I.R.) C. End Play D. Crank Flex Crank run out can be checked by installing the end main bearing caps, and setting up a dial indicator on the center of the crank. Run out should be zero!

45 Knock heard at most speeds, but goes away when a cylinder is denied its spark or fuel A. Rod Bearing B. Main Bearing C. Wrist Pin D. Piston Slap

46 Polished bearing surface on a crankshaft A. Thrust Plate B. Full Round Bearing C. Precision Insert D. Bearing Journal

47 Measure a Standard Main Journal Diameter:

48 Measure a Standard Main Journal Diameter: 2 to 3 Micrometer 2 to 3 Micrometer

49 Measure a Standard Rod Journal Diameter: 1 to 2 Micrometer 1 to 2 Micrometer

50 Measure a Metric (mm) Main Journal Diameter:

51 Measure a Metric (mm) Main Journal Diameter:

52 Measure a Metric (mm) Rod Journal Diameter:

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61 1 2 Micrometer Micrometer

62 0 25 mm Micrometer mm Micrometer