Session 3: Inspection and Replacement of Sleeves, Connecting Rod and Engine Bearing
Module 2: Serviceability, Replacement or Repair of Engine Components
Textual Question-Answers
Check Your Progress
Fill in the blanks
1. In an engine, the cylinder liner, also known as a ……………inside of the cylinder to protect it from wear and damage. lines theAns: bore sleeve
2. If a connecting rod is damaged beyond repair, it needs to be…………with a new one.
Ans: replaced
3. One of the indicators of worn-out engine bearingsis the presence of ………..in the oil.
Ans: metal particles
4. Inspecting the ……….. of the crankshaft is done using a dial gauge to check for runout or bending.
Ans: alignment
Multiple Choice Questions
1. What is the purpose of a cylinder liner or bore sleeve in an engine?A) To hold the spark plugs
B) To line the inside of the cylinder and protect it
C) To connect the piston to the crankshaft
D) To control the flow of coolant
Ans: B) To line the inside of the cylinder and protect it
2. What is the primary reason for inspecting the cylinder liner?A) To check the color of the liner
B) To ensure proper coolant flow
C) To measure the piston size
D) To identify wear, scratches, or damage
Ans: D) To identify wear, scratches, or damage
3. What could cause scratches on a cylinder liner?
A) Excessive coolant flow
B) Incorrect piston size
C) Piston ring sticking
D) Too much engine oil
Ans: C) Piston ring sticking
4. The connecting rod in an engine serves to:
A) Direct the flow of air
B) Convert rotational motion to up-and-down motion
C) Hold the fuel injectors
D) Control exhaust gas emissions
Ans: B) Convert rotational motion to up-and-down motion
Answer the following questions
1. What is the function of connecting rod?
Ans: The connecting rod connects the piston to the crankshaft and convertsthe reciprocating motion of the piston into rotary motion of the crankshaft.
2. Why do some connecting rod have hole drilled from small end tothe big end bearing?
Ans: The hole is drilled to allow lubricating oil to flow from the small endto the big end bearing for proper lubrication and cooling.
3. Which parts are connected to the small end of the connectingrod?
Ans: The piston is connected to the small end of the connecting rod throughthe gudgeon pin.
4. Which part of connecting rod is connected with crankshaft?Ans: The big end of the connecting rod is connected with the crankshaft.
5. How to check bend in connecting rod?
Ans: Bend in a connecting rod is checked using a connecting rod aligneror by placing it on a surface plate and checking with a dial gauge.
6. How to check clearance between connecting rod and crankshaft?Ans: The clearance is checked using plastigauge or by measuring thejournal and bearing with a micrometer and bore gauge.
Activity
1. Make a list of steps required for inspection and replacement ofcylinder liner or bore sleeve
Ans:
S. No. Steps
1. Drain engine oil and coolant
2. Remove cylinder head, piston, and connecting rod
3. Inspect the liner for wear, scratches, taper, and ovality
4. Remove damaged liner, fit new liner, and reassemble engine
5. Make a poster showing ovality and taperness
Ans: The students should try themselves.
