Question 1

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

Accepted Answer

Using a hammer directly on engine halves can cause damage to the precision surfaces. Proper disassembly techniques and tools should be used to avoid damaging the engine.

Question 2

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

Accepted Answer

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.

Accepted Answer

Trochoid oil pumps are commonly used in four-stroke motorcycle engines due to their efficiency and compact design.

Question 4

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

Accepted Answer

Plastigage is a tool used to measure the clearance between the journal and bearing in a plain bearing engine by compressing a thin strip of plastic material and measuring its width.

Question 5

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

Accepted Answer

The answer of How do you check the transmission before...

Question 6

Plain bearings are color coded.

Accepted Answer

Plain bearings are color coded to indicate their material composition and performance characteristics.

Question 7

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

Accepted Answer

The answer of Connecting rods in a four-stroke engine have...

Question 8

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

Accepted Answer

A slipping clutch can often be diagnosed and inspected through symptoms and tests without the need to remove the engine, as the clutch assembly is usually accessible through the transmission.

Question 9

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

Accepted Answer

The answer of Explain how you would identify the location...

Question 10

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

Accepted Answer

Cassette transmissions are designed to be removed as a single unit or "cassette" without the need to split the case halves, allowing for easier maintenance and gear changes.

Question 11

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

Accepted Answer

The answer of Describe how you break in a new...

Question 12

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

Accepted Answer

The answer of Describe the procedure to identify the connecting...

Question 13

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

Accepted Answer

Clunking noises, especially when shifting gears, can indicate a problem with the transmission, such as worn gears or issues with the transmission fluid.

Question 14

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

Accepted Answer

A feeler gauge is the correct tool for measuring the clearance between the tip and body of a rotor type oil pump because it allows for the measurement of narrow gaps which cannot be accurately measured with tools like micrometers or calipers.

Question 15

Babbitt bearings are used in some four-stroke engines.

Accepted Answer

Babbitt bearings, also known as white metal bearings, are used in various applications including some four-stroke engines for their properties of low friction and good conformability.

Quiz 13: Four-Stroke Engine Lower-End Inspection