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9LD Workshop Manual _ cod. 1.5302.286 - 3° ed_rev. 02
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Distance between the piston at the top dead centre and the
cylinder surface
Head seal thickness
Disassembly / Reassembly
CONNECTING ROD
Remove the oil sump.
Remove the connecting rod cap.
Important
Both connecting rod/piston units should be fitted back into the
corresponding cylinders; mark them so as to identify the correct
combination during reassembly.
 See page 40 for specifications as to the tightening of the connecting
rod big end bearing.
Piston clearance
Piston clearance = 0.65 ÷ 0.70 mm, for standard engines
=0.55 ÷ 0.60 mm, for 97/68 CE and EPA engines
The piston in the TDC (top dead centre) position may extend or be
short of the upper surface of the cylinder.
Use a dial indicator to measure the difference between the two
surfaces (piston crown and upper cylinder surface) and use a suitable
thickness copper gasket B for the cylinder head to adjust the
clearance volume A.
(See image below)
Piston - Refitting
Connect piston to connecting rod in a way that the combustion chamber
centre b is at right angle under nozzle tip a.
Lubricate piston pin and introduce it into the piston by exerting pressure
with your thumb.
Check that both circlips are well inside their seats.