Checking The Connecting Rods; Checking Connecting Rod Straightness; Check For Twisting; Check The Connecting Rod Assembly Bolts - Nanni T4.155 Workshop Manual

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4. CHECKING THE CONNECTING RODS

A. Checking connecting rod straightness
Check the straightness of connecting rods with a set of thickness
shims by installing them on the connecting rod square.
a) Check whether there is any bending.
Bending limit:
Replace the connecting rod assembly when bending exceeds the
indicated limit.
b) Check for twisting
Twisting limit:
Replace the connecting rod assembly when twisting exceeds the
indicated limit.
B. Check the connecting rod assembly bolts
Use a Vernier caliper to check the minimum diameter of the
compressed section of the bolt thread at the location where the
measurement must be made.
Nominal diameter:
Diameter limit
Replace the connecting rod bolt when the diameter is less than the
specified limit.
C. Check piston pin lubrication clearance
a. Use a diameter measurement tool to measure the internal
diameter of the connecting rod small end bush.
Inner diameter of the connecting rod small end bush:
34.012 – 34.024 mm
b. Use a micrometer to measure the diameter of the piston pin.
Piston pin diameter:
4 CYLINDERS WORKSHOP MANUAL
0.03 mm for 100 mm
0.15 mm for 100 mm
8.400 – 8.600 mm
8.20 mm
34.000 – 34.012 mm
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