Lombardini LDW 502, Service Manual

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service manual
mod. 051135
6
B
A
6.5 DIAGRAM OF TIMING BELT RATES
Rotate the crankshaft clockwise to find out the
timing rates of the entire cycle in each cylinder
(operation and control).
Timing belt operating angles (valve
clearance 0.25 mm)
α αα
αα
= 14° before S (top ded centre)
βββββ
= 38° after I (bottom dead centre)
γγγγγ
= 34° before I (bottom dead centre)
δδδδδ
= 18° after S (top ded centre)
Timing belt control angles (valve clearance
2 mm)
α αα αα
= 25° after S (top ded centre)
βββββ
= closes 2° dopo I (bottom dead centre)
γγγγγ
= 5° after I (bottom dead centre)
δδδδδ
= 18° before S (top ded centre)
6.6 ADJUSTING STATIC INJECTION TIMING
In order to adjust injection timing, it is necessary
to remove the rocker arm cover.
See “Disassembling rocker arm cover” for the
correct procedure.
1 - Disassemble the injector pump fuel rail (A).
2 - Select the cylinder on which the injection
static advance adjustment will be carried
out.
3 - Unscrew the rocker arm support nut (B)
corresponding to the cylinder on which the
procedure will be carried out.
Legenda
S = piston at top dead centre
I = piston at bottom dead centre
α = α =
α = α =
α =
intake valve open
β = β = β = β = β =
intake valve closed
γ = γ = γ = γ = γ =
exhaust valve open
δ = δ = δ = δ = δ =
exhaust valve closed
OVERHAULS AND TUNING