DS 19 OPERATION No. DS 112-4 : Work on the cylinder head. Op. DS 112-4 77
PARTICULAR POINTS
Replacement of an inlet rocker assembly.
Removal.
1 Drain the radiator and the cylinder block.
4 It is necessary to remove the last exhaust rockershaft, in order to allow the removal of the last fixing screw of the inlet rockershaft and the
cylinder head (remove the 4
th
exhaust rockershaft, the first five fixing screws of the inlet rockershaft, the washer and the spring of the 1
st
inlet rocker, in order to disengage the inlet rockershaft with its rear bracket).
Assembly
8 Make sure that the cylinder head fits correctly on the centering dowels.
When fitting the inlet rockershaft and rear bracket assembly, position the lubrication holes of the rockershaft towards the bottom, valve side.
Tighten the cylinder head: 1
st
tightening 21.75 ft/lb (3 m.kg), 2
nd
tightening 43.5 ft/lb (6 m.kg) (do not exceed the tightening torsion and
observe the order of tightening indicated on Pl.7. Make sure that the push rods are correctly positioned).
10 Adjust the valve rocker clearances: inlet = 0.008 in (0.20 mm), exhaust 0.010 in (0.25 mm) (see Op. 112-0).
14 Fill the water cooling system, the vane of the heater control open (bleed).
Replacement of an exhaust valve rocker assembly.
In order to replace a bracket, it is necessary to remove the inlet rockershaft (see above).
Replacement of an inlet valve sealing ring or spring.
Removal.
29 Drain the radiator and cylinder block. Unscrew the cylinder head fixing screws.
Raise the inlet rockershaft, in order to disengage the push-rod of the valve in question and put the rockershaft in position.
30 With piston of the valve in question at top dead centre, release the rocker at the side, place the collar MR-4244 in position and compress
the valve springs.
If necessary, release the cup retaining cotters with a light tap with a hammer.
Assembly.
33 Raise the inlet rockershaft, in order to put the removed push-rod into position (see paragraph 29).
34 Tighten the cylinder head: 1
st
tightening 21.75 ft/lb (3 m.kg), 2
nd
tightening 43.5 ft/lb (6 m.kg) ( do not exceed the tightening torsion and
observe the order of tightening indicated on Pl.7. Make sure that the push rods are correctly positioned).
35 Check the valve rocker clearances: inlet = 0.008 in (0.20 mm), exhaust 0.010 in (0.25 mm) and adjust if necessary.
To Next Page
Loading...
