1199 / 1525
ENGINE
32
CONNECTING ROD :
Standard and Repair sizes of connecting rod big end bearing.
Bearing bore in
Wall thickness of bearing
installed condition.
shells ready for installation.
mm.
mm.
Standard
60.085/60.065
2.462/2.472
Standard – I
59.985/59.965
2.512/2.522
Repair size – I
59.835/59.815
2.587/2.597
Repair size – II
59.585/59.565
2.712/2.722
Repair size – III
59.335/59.315
2.83712.847
Repair size – IV
59.085/59.065
2.96212.972
Connecting rod big end bearing parent bore
65.016/65.00
mm
Maximum permissible taper and ovality in big end bearing parent bore
0.005
mm
Pretension of connecting rod bearing shells
0.08-0.14
mm
Diametral clearance between crank pins and connecting rod big end
0.050-0.095
mm
bearings
End play of connecting rod
0.100-0.400
mm
Maximum permissible out of parallelism (bend) between small end and
0.025
mm
big end bores (at 50 mm from centre axis)
Maximum permissible twist of connecting rod (at 50 mm from centre axis)
0.10
mm
Measure the twist and bend of connecting rod with a feeler gauge with respect to vertical face of the connecting
rod alignment gauge in vertical and horizontal planes and at a distance of 50 mm from the line joining centres of
small and big end bosses. If necessary straighten the connecting rod in cold condition.
Standard and Repair sizes of connecting rod small end parent bore and bush:
Parent bore
Bush outside diameter
mm
mm
Standard
39.025/39.000
39.075/39.045
Repair size – I
39.225/39.200
39.275/39.245
Repair size – II
39.525/39.500
39.575/39.545
Maximum permissible taper and ovality in small end parent bore.
0.01
mm
Maximum permissible taper and ovality in small end bush bore.
0.005
mm
Connecting rod bush inside dia
36.04/36.03
mm
(finished size after installation)
Piston pin outside dia
36.000/35.995
mm
Radial clearance between piston pin and bush
0.03-0.045
mm
Connecting rod big end centre to small end centre distance.
182.05/182.00
mm
Permissible difference in weight of connecting rods in the engine
10
gm