Opel Kadett Owner's Manual page 58

2C•8 DOHC (16-valve) engine
11.24a Cylinder head bolt tightening
sequence
25 The remainder of refitting is a reversal of
the removal procedure, noting the following
points:
a) Use new gaskets on the thermostat
housing, the manifolds and the camshaft
cover (see illustration).
12.4 Removing a tappet. Note the oil ring
(arrowed)
12.5 Detail of valve spring compressor
head and tube
12.6c . . . the valve spring . . .
11.24b Angle tightening a cylinder head
bolt
b) Use a new camshaft toothed belt and
tension it as described in Section 7.
c) Tighten all fastenings to the specified
torque.
d) Run the engine until the cooling fan cuts
in. If the hydraulic tappets have been
disturbed, they may be noisy for a few
minutes until they settle down. Switch the
engine off, remove the camshaft cover
again and tighten the cylinder head bolts
through the final specified stage.
12 Cylinder head - overhaul
1 Remove the manifold gaskets
2 Remove the camshafts, slackening the
bearing cap nuts progressively until the valve
spring pressure is released.
3 Remove the spark plugs.
12.6a Remove the valve . . .
12.6d . . . the valve stem oil seal
(arrowed) . . .
11.25 Fitting a new gasket to the camshaft
cover
4 Using a sucker or a magnet, remove the
hydraulic tappet buckets from their bores (see
illustration). If they are to be re-used, keep
them in order so that they can be refitted to
their original locations. To stop the oil draining
out of them, store them in a bath of clean
engine oil with the oil ring lowermost.
5 Prepare a box with 16 compartments to
receive the valve components. Using a valve
spring compressor and a piece of tube with
two slots cut in it, compress a valve spring
(see illustration). Extract the collets from the
top of the valve stem using a pencil magnet or
a magnetic screwdriver.
6 Carefully release the compressor and
remove the valve, the spring upper seat and
the spring. Pull off the valve stem oil seal with
longnosed pliers and recover the valve spring
seat. Place all the components in the
appropriate compartment in the box (see
illustrations).
12.6b . . . the spring upper seat . . .
12.6e . . . and the valve spring seat