Connecting Rod - Yanmar 4LHA-HTP Operation Manual

Chapter 2 Basic Engine

6. Connecting Rod

6. Connecting Rod
The connecting rod is made of high-strength forged car-
bon steel.
The large end with the special aluminum-alloy metal
can be separated into two and the small end has a copper
alloy coil bushing.
Connecting rod —
(big end cap)
Connecting rod
6-1 Inspecting the connection rod
6-1.1 Twist and parallelism of the large and small ends
Insert the measuring tool into the large and small ends of
the connecting rod. Measure the extent of twist and
parallelism and replace if they exceed the tolerance.
Measuring parallelism
Piston pin bushing
Lube, oil hole
Crank pin metal
- —Connecting rod bolt
Parallelism
Measuring twist
Connecting rod
twist and parallelity
6-1.2 Checking thrust clearance
Fit the respective crank pins to the connecting rod anc
check to make sure that the clearance in the crankshaf
direction is correct.
Connecting rod side
clearance
2-25
.4LHA Series
mm (in.^
Standard Wear limit
0.05/100 or less 0.2
(0.0020/3.94) (0.0079)
Feeler gauge
mm (in.)
Wear limit
Standard
0.45
0.2 - 0.4
(0.0177)
(0.079-0.0157)