Lombardini LDW 502, Руководство по обслуживанию

Страница: 45 / 98

- 45 -
service manual
mod. 051135
6
D
V
d 5 2 0 , 0 1 1 ÷ 5 7 9 , 9 0 1
c Ø - b Ø
5 2 0 , 0 ÷ 0 1 0 , 0
0 4 , 0
b Ø 0 2 0 , 0 2 ÷ 0 1 0 , 0 2
c Ø 0 0 0 , 0 2 ÷ 5 9 9 , 9 1
a Ø 5 3 0 , 0 4 ÷ 0 2 0 , 0 4
e 0 2 0 , 5 5 ÷ 0 0 0 , 5 5
6.2.6 Dimensional check and overhaul of
connecting rods
1 - Check that the contact surfaces are
perfectly clean and intact.
2 - Assemble the cap (N) onto the connecting
rod big end and tighten the screws to a
torque of 38 Nm.
3 - Using a micrometer, measure diameters
øa-b.
Important
– If the diameter of the conncting rod
small end does not match the diameter
of the wrist pin, the connecting rods
must be replaced to achieve the right
match (see “Table of connecting rod
dimensions”).
– The half-bearings are supplied smaller
than the nominal dimensions, by 0,25
mm and 0,50 mm.
– Before replacing the connecting rods,
check that the weight difference does
not exceed 10g to prevent weight
imbalances (see “Table of connecting
rod dimensions”).
– Protect the contact surfaces with
lubricant oil, to prevent them from
rusting.
Important
Protect the contact surfaces with lubricant
oil, to prevent them from rusting.
6.2.7 Checking parallelism of the
connecting rod axes
1 - Insert the wrist pin (V) in the connecting
rod small end.
2 - Use a dial indicator to check that there is
parallelism between the small end and big
end axes. Parallel deviation, measured at
the very tip of the wrist pin, must not
exceed 0.015-0.030mm. If parallel values
do not correspond to those indicated,
replace the connecting rod with an original
spare.
3 - After carrying out all checks and overhauls,
remount the connecting rods, pistons and
sealing rings (see “Pre-assembly of sealing
rings - pistons” and “Pre-assembly of
connecting rods - pistons”).
connecting
rod small end
connecting
rod
connecting
rod big end
connecting
rod
Table of connecting rod dimensions
Dimensions
Clearance
(mm)
wear &
tear limit
(mm)
Ref.
OVERHAULS AND TUNING