Assembling And Tightening The Cylinder Head On Engines With Hydraulic Tappets; Cylinder Head Tightening Steps - Kohler LAMBARDDINI LDW 1503 Workshop Manual

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57
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Reassemble the complete pin inserting the seats of the rocker-arms on their respective rods and screw up the fastening screws
of the supports by hand.
Important
• To avoid bending the push rods or damaging the tappets, the fastening screws of the rocker-arm pin supports must be tightened
gradually before reaching the final torque.
This procedure will give time for the excess oil in the tappets to drain away.
Each time you start to tighten up the fastening screws of the supports, you can use the upper spring support cup of the valve spring
as an indicator to know how far to screw them up.
The cup must never be compressed so much that it touches the valve stem oil sealing ring fitted on the guide.
Workshop Manual LDW CHD _ cod.
Disassembly / Reassembly
Cylinder head tightening for engines without hydraulic
tappets
Use a torque wrench (fitted with tool for angular tightening).
It is recommended to replace the screws whenever the head is
disassembled.
• The cylinder head must never be retightened.
• It is advisable to lubricate the lower part of the screws with anti-
seize of the type MOLYSLIP AS COMPOUND 40.

Cylinder head tightening steps

Following the number sequence shown in the figure 57 bolts
should be tightened in four susequent steps with the following
LDW 1503
torque values:
1603
1st step = 40 Nm
2nd step = 70 Nm
3rd step = 100 Nm
4th steps =
LDW 2004
2004/T
2204
2204/T
Assembling and tightening the cylinder head on engines
with hydraulic tappets
• Before re-assembling the cylinder head the tappets must be
removed from their housing and released.
This operation must be carried out using a pin 1.
Insert pin 1 inside the tappet and open the non-return valve.
The excess oil is released by turning the tappet upside down.
Rotate the crankshaft so as to position the pistons at half stroke
for three-cylinder engines.
For four-cylinder engines, place the piston of cylinder number one
at 150° after the top dead centre (in crossover stage).
Fit the head, insert the fastening screws and tighten them in the
order shown in figure 57 and to their respective torques (see
"Cylinder Head Tightening Stage).
ED0053031210 - 1° ed_rev. 00
Important
For bolts 10 R: Rotate wrench by 180° (in two
steps 90°+90°)
For bolts 12 R (present only in the TURBO
engines): perform a rotation of the key of 270° (in
three steps, 90° + 90°+ 90°).
Important
4
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