Lombardini LDW 502, Руководство по обслуживанию

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service manual
mod. 051135
6
x Ø 0 2 0 , 7 ÷ 5 0 0 , 7
c Ø - b Ø
5 0 0 , 0 ÷ 5 0 , 0
0 1 , 0 y Ø 0 9 9 , 6 ÷ 0 6 9 , 6
Z 0 , 6 4 ÷ 5 , 3 4
W 8 , 0 ÷ 5 , 0 1 , 1
J 7 , 1 ÷ 6 , 1 0 , 2
If the length does not correspond to the value
shown, replace the springs with original spares.
2 - Use a micrometer to measure the
diameters of the valve stems and guides
(see “Table of dimensions for springs –
valve stems – valve guides”). If the
diameters do not correspond to the values
show, replace the valves and guides with
original spares.
Important
Take measurements in several places in
order to discover possible ovalization and/
or wear.
3 - Thoroughly clean the valves and their seats.
4 - Measure the width of the seal for each valve (J) and
the indentation (W) from the flat part of the cylinder
head (see “Table of dimensions for springs – valve
stems – valve guides”). If the dimensions do not
correspond to the values shown, replace the valve seat
ring with an original spare.
5 - Use a pointed tool to take out the valve seats.
6 - Remove any debris, clean the valve seat holder carefully
and scrape the mouth.
7 - Lubricate the new valve seats and put them into the
holder manually.
6.3.5 Checking and overhaulimg the valves
In order to carry out a control of the valves, it is
necessary to remove them from the cylinder
head. See “Disassembling the valves” for the
correct procedure.
1 - Use a gauge to measure the length of the
springs (see “Table of dimensions for
springs – valve stems – valve guides”).
Table of dimensions for springs - valve stems
- valve guides
8 - Use the special tool to put the valve seats in the holder.
9 - Slide the valves into their seats.
10 - Measure the degree of indentation of each valve from
the flat part of the cylinder head (see “Table of
dimensions for springs – valve stems – valve guides”).
Se le dimensioni rilevate corrispondono ai valori
indicati, smerigliare ogni valvola nella propria sede.
Important
Protect the contact surfaces with lubricant oil, to
prevent them from rusting.
11 - Assemble the valves (see “Assembling the flywheel”).
Dimensions
(mm)
Clearance
(mm)
Wear &
tear limit
(mm)
Ref.
valve guide
valve guide
valve
guide
valve seat
OVERHAULS AND TUNING