Lombardini 9 LD 625-2 EPA, Workshop Manual

Page: 47 / 88

- 47 - 9LD Workshop Manual _ cod. 1.5302.286 - 3° ed _rev. 02
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Disassembly / Reassembly
Valve timing - Angles
The angle values are determined by turning the driving shaft clockwise
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
γγγγγ
= Exhaust valve open
δ δδ
δδ
= Exhaust valve closed
Timing angles for checking puposes
(valve clearance = 0,65÷0,70 mm)
α α α α α
= 1° before S
β β β β β
= 21° after I
γγγγγ
= 23° before I
δ δδ
δδ
= 1° after S
HYDRAULIC PUMP
Hydraulic pump p.t.o
A hydraulic pump of group 1 ( 1P ) or 2 ( 2P ) can be installed on the gear
side, 3rd p.t.o.
Valve timing check
Check valve timing at the crankshaft.
The values shown are checked at the flywheel circumference (with
flywheel of 291 mm. diameter each degree corresponds to 2.5 mm).
Set valve clearance at 0.65÷0.70 mm (after checking restore the value
at 0.15÷0.20 mm).
Set dial gauge on intake valve to a zero value; by rotating the driving
shaft according to its direction of rotation you can measure
α α α α α
(intake
valve opening advance referred to top dead centre S ) and ß (intake valve
closing delay referred to bottom ( I ) dead centre).
Follow the same procedure for exhaust valves checking
γγγγγ
(exhaust valve
opening advance) and
δ δδ δδ
(exhaust valve closing delay).