Lombardini CHD series - Valve Timing Procedures; Camshaft timing; Valve timing without considering timing marks; Valve timing check

- 54 - Workshop Manual LDW CHD _ cod. 1.5302.345 - 6° ed_rev. 05
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Disassembly / Reassembly
Valve timing without considering timing marks
Locate piston 1(onywheel)atthetopdeadcenter.Positiontwo
small rods A of the same length onto the tappets.
Rotate camshaft stopping when cylinder 1 tappets are in overlap
position (intake open exhaust closed).
Using the straight edge B check that rods A are at the same
length.
Mark the idler gear with camshaft and timing gear.
Camshaft timing
Fit idler gear B by making timing mark 2 coincide with timing
mark 1 on the camshaft control gear A and mark 3 with 4 on the
timing gear C.
Valve timing check
Check valve timing at the crankshaft.
Thevaluesshownarecheckedattheywheelcircumference(with
ywheeldiameterof290eachdegreecorrespondsto2.53mm).
Set valve clearance at 0.65-0.70 mm (after checking reset the
value to 0.15 mm).
Set dial gauge on intake valve to a zero value; by rotating the
crankshaft according to its direction of rotation you can measure
α
(intake valve opening advance referred to top dead center S) and
β (intake valve closing delay referred to bottom dead center I).
Follow the same procedure for exhaust valves checking
γ (exhaust
valve opening advance )and
δ ( exhaust valve closing delay).