63
ASSEMBLY
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Fit the decompressor weight (4) and the relative
spring (5). The spring must be preloaded by half a
turn when fitted. Then check that the decompressor
mass returns automatically to its initial position af-
ter being displaced. If this does not happen, replace
the spring.
N.B. Oil the contact areas between the decompressor
mass and the other parts in the camshaft assembly.
4.17.2 Fitting the valvegear
Fit the head (1) onto the cylinder, tapping it several
times in the area of the dowels in order to facili-
tate seating. Fit the washers (2) and screw the nuts
(3) onto the studs, tightening them in diagonal se-
quence, starting with the studs in proximity to the
dowels, after applying molycote grease. Tighten in
diagonal sequence to 30 Nm. Then, using a pro-
tractor disc (A), continue tightening the nuts on the
studs, forcing them through a rotation of 70°. If such
a tool is not available, tighten the nuts to 50 Nm.
Tighten the M6x25 bolt (4) to 10 Nm.
Fit the water pump drive sprocket (5) into its hous-
ing in the timing case, with the smaller-diameter
face towards the inside, and then the water pump
shaft (6) after you have lubricated it with oil.
Check the diameter of the water pump shaft in the
area where it makes contact with the seals. Signs of
wear may be visible in this area. If the diameter is
less than the limit value, replace the shaft to avoid
sealing problems.
Minimum diameter 9.7mm
4
5
A