95
Fig. 8.7
B1 A1
D
C
B2
A2
B
Tab. 8.5
ED0053030410
INFORMATION ABOUT OVERHAULING
8.4 Crankshaft
8.4.1 Dimensional check and overhauling
Wash the crankshaft thoroughly using suitable detergent.
Insert the pipe cleaner into all lubrication ducts B and blow
compressed air to free them completely from any dirt residues.
Check the state of wear and integrity of journals C and
connecting rod D.
Perform the operations described in Par. 9.3.1 and Par. 9.3.5
- except points 2, 3, 5, 9 and 10.
Tighten capscrews J (Fig. 9.9) and K (Fig. 9.10) observing
the cycles, tightening, and subsequent rotation.
Cycle 1 - Screw J - Torx M14x1,5 - Torque 60 Nm. (Fig. 9.9)
Cycle 2 - Screw K - Torx M10x1.25 - Torque 30 Nm. (Fig. 9.10).
Measure the crank pins A1 with a micrometer, and using a
dial gauge measure the internal diameter of the connecting
rod half-bearings A2. Measure the main journals B1, with
a micrometer, and using a dial gauge measure the internal
diameter of the crankshaft half-bearings B2. If the values
described in Tab. 8.5 do not correspond, proceed with grinding
all gudgeon pins A1 e B1.
Important
• The crankshaft and connecting rod must be replaced every
time they are assembled to prevent seizure, as they are made
of special lead-free material.
• The MAX allowed value of wear for A1 e A2 is 0.120 mm.
• The MAX allowed value of wear for B1 e B2 is 0.120 mm.
• To grind the crankshaft, a decrease in diameter of the half-
bearings and connecting rod is provided for at 0.25 mm and
0.50 mm, to grind gudgeon pins A1 and B1, measure the
values of diameters A2 and B2 by assembling the decreased
half-bearings, define the diameter to grind of pins A1 and B1,
observing the clearance indicated in Tab. 8.5.
• Tab. 8.5 details the dimensional values of new components
only.
REF. DIMENSIONS (mm)
CLEARANCE
VALUE (mm)
A1 60.980 - 61.000
0.034 - 0.09
A2 61.034 - 61.069
B1 79.978 - 80.000
0.036 - 0.10 4
B2 80.036 - 80.082
Connecting rod and journal diameter
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