ase a 1 test preparation - school district of grafton engine has push rods & rocker arms: [ ]...
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Advanced Auto Tech ASE A 1 Test Preparation
Engine Lower End Theory & Service
To make work easier, one of the first steps often done before engine removal is to clean & degrease the engine compartment.
True or
False
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
Wearmated parts should be marked, labeled & kept organized to assist with failure analysis.
True or
False
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
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
Magnetic crack detection on ferrous parts is often referred to by its trade name Magnafluxing ® …there is also a dye method for use on nonferrous metal (aluminum & magnesium) components.
True or
False
Low engine oil pressure can be an indicator of main bearings with insufficient oil clearance…more often than oil pump issues.
True or
False
Low engine oil pressure can be an indicator of main bearings with insufficient oil clearance…more often than oil pump issues.
Camshafts always turn at twice the crankshaft RPM. 360º of cam rotation & 720º of crank rotation in a 4 stroke cycle.
True or
False
To determine piston ring groove wear, side clearance should be measured using new piston rings.
True or
False
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
Wrist pins are offset toward the major thrust surface of the cylinder in an effort to eliminate piston slap.
True or
False
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
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
Following cylinder honing or deglazing, how & with what should the engine block be cleaned?
After block line boring, a block must be fit with bearings that are: [ ] standard size [ ] under size [ ] over size
After crank main journal regrinding, a block needs bearings that are: [ ] standard size [ ] under size [ ] over size
Which engine has push rods & rocker arms: [ ] overhead valve [ ] overhead cam [ ] rotary [ ] Fhead
Determine the displacement of a cylinder & 4 cylinder engine with 3.000 Bore & a 4.000” Stroke: B x B x S x .785 x # of Cyls. = Disp.
Top Dead Center
Bottom Dead Center
Determine the displacement of a cylinder & 8 cylinder engine with 3.500 Bore & a 4.250” Stroke: B x B x S x .785 x # of Cyls. = Disp.
Top Dead Center
Bottom Dead Center
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.
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.
What tool is used to remove or ream the cylinder ring ridge out of the top of the cylinder prior to piston removal?
How is compression ratio mathematically determined?
http://performancetrends.com/
Which parts in an engine block control crankshaft end play? Or…which parts could be worn & result in excessive end play?
Distance measured from TDC to BDC in the cylinder:
A. Stroke B. Taper C. OutofRound D. Crank Throw
Loud, dull knock from the lower end of the engine block
A. Rod Bearing B. Main Bearing C. Wrist Pin D. Piston Slap
Also known as freeze plugs
A. Spark Plugs B. Core Plugs C. Pipe Plugs D. Expansion Tubes
Top piston ring
A. Scraper or Wiper Ring B. Segmented Ring C. Oil Control Ring D. Compression Ring
Double knock heard at engine idle speeds
A. Rod Bearing B. Main Bearing C. Wrist Pin D. Piston Slap
Precision insert bearing surface coating that is an alloy of: tin, copper, and antimony
A. Babbit B. Assembly Lube C. Anaerobic D. RTV Aerobic
Connecting rod journal
A. Rod Bearing B. Main Bearing C. Wrist Pin D. Crank Pin
Bottom piston ring
A. Bauk Ring B. Blocking Ring C. Oil Control Ring D. Compression Ring
Determined by comparing TDC and BDC cylinder diameters
A. Stroke B. Taper C. OutofRound D. Compression Ratio
Cylinder diameter
A. Stroke B. Taper C. OutofRound D. Bore
Distance from the centerline of the main journal to the centerline of the rod journal on the crankshaft
A. Stroke B. Taper C. OutofRound D. Crank Throw
Fastens the piston to the upper end of the connecting rod
A. Rod Bearing B. Main Bearing C. Wrist Pin D. Crank Pin
Harmonic balancer used to dampen crankshaft torsional vibration
A. Saddle Bore B. Bearing Saddle C. Vibration Damper D. Pilot Bearing
Determined by comparing bore diameters measured 90º to each other at the top of the cylinder
A. Stroke B. Taper C. OutofRound D. Crank Throw
Engine block main bearing centerline
A. Saddle Bore B. Bearing Crush C. Bearing Spread D. Bearing Clearance
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.
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.
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
Right angle movement of the crankshaft while in vblocks 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 runout can be checked by installing the end main bearing caps, and setting up a dial indicator on the center of the crank. Runout should be zero!
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
Polished bearing surface on a crankshaft
A. Thrust Plate B. FullRound Bearing C. Precision Insert D. Bearing Journal
Measure a Standard ” Main Journal Diameter:
Measure a Standard ” Main Journal Diameter:
2” to 3” Micrometer
2” to 3” Micrometer
Measure a Standard ” Rod Journal Diameter:
1” to 2” Micrometer
1” to 2” Micrometer
Measure a Metric (mm) Main Journal Diameter:
Measure a Metric (mm) Main Journal Diameter:
Measure a Metric (mm) Rod Journal Diameter:
2152010
2152010
57.00 00.50 00.49 57.99
2152010
2152010
46.00 00.50 00.40 46.90
2152010
2152010
2.000 0.200 0.025 0.009 2.234
2152010
2152010
2.000 0.100 0.009 2.109
1” 2” Micrometer
2” 3” Micrometer
1.000 0.500 0.050 0.015 1.565
2.000 0.400 0.050 0.018 2.468
17.00 00.00 17.00
7.00 0.12 7.12