Deck 13: Four-Stroke Engine Lower-End Inspection

Question 1

Use a hammer to assist in separating the engine halves on a four-stroke engine.

Answer 1

False

Question 2

Detail how you inspect a crankshaft and its journals and what you should do to the oil holes in the crankshaft.

Answer 2

Inspect the connecting rod journals closely for signs of scoring or roughness. You should measure the bearing surfaces with a micrometer and check your measurements against the service manual. Check the crank for run-out and be sure to verify that the holes in the crankshaft are free from obstructions of any kind.

Question 3

A _______ oil pump is used in the majority of four-stroke motorcycle engines.

A)gear
B)plunger
C)centrifugal
D)trochoid

Answer 3

D

Question 4

______ is used to measure the clearance between the journal and bearing in a plain bearing engine.

A)Plastigage
B)Prussian blue
C)Litmus paper
D)Dykem

Question 5

How do you check the transmission before the rest of the engine is assembled?

Question 6

Plain bearings are color coded.

Question 7

Connecting rods in a four-stroke engine have ______ stamped on them for information purpose.

A)ID numbers
B)codes
C)clearance specifications
D)"born on" date

Question 8

You will have to remove the engine to inspect a slipping clutch.

Question 9

Explain how you would identify the location of the shift forks when reassembling the engine.

Question 10

A ______transmission can be removed from the cases without separating the halves.

A)direct drive
B)cassette
C)primary kick
D)constant mesh

Question 11

Describe how you break in a new engine and the precautions you should observe when doing so.

Question 12

Describe the procedure to identify the connecting rods and what you should do to the rod caps and bearings.

Question 13

An excessive clunking noise is a characteristic sound that indicates a transmission problem.

Question 14

Measure the clearance between the tip and body of a rotor type oil pump with a________.

A)micrometer
B)small bore gauge
C)feeler gauge
D)caliper

Question 15

Babbitt bearings are used in some four-stroke engines.