Lombardini LDW 502, Руководство по обслуживанию

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service manual
mod. 051135
6
A
6.4 CHECKING TIMING BELT RATING
6.4.1 Valve adjustments
1 - Bring the piston to the compression top
dead centre.
2 - Adjust the screw (A) and the lock nut in
order to adjust the rocker arm valve
clearance to 2 mm.
3 - Rotate the crankshaft clockwise through
360° in order to make the piston reaching
the balancing top dead centre.
4 - Apply a magnetic goniometer on the
crankshaft pulley and set it to zero.
5 - Place two dial indicators on the collars of
the intake and exhaust valves, then set
them to zero.
6 - Rotate the crankshaft clockwise until the
dial indicator moves away from zero.
7 - Measure the rotation angle of the crankshaft
by using the magnetic goniometer.
The value registered indicates when the
intake valve starts opening.
8 - Go on rotating the crankshaft clockwise
until the dial indicator stops at point “0”.
9 - Measure the rotation angle of the crankshaft
by using the magnetic goniometer.
The value registered indicates when the
intake valve starts closing.
The values registered must coincide with
those indicated on the timing angle
diagrams (see “Distribution timing angle
diagram”).
10 - Repeat these procedures on the other
valves.
Fan drive pulley
magnetic
goniometer
Intake
valve
Exhaust
valve
OVERHAULS AND TUNING