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Cylinder Head
3---1
3. CYLINDER HEAD
A. Removing cylinder head
1. Clean the engine externally and drain the coolant. Discon-
nect the coolant hoses from the cylinder head and the thermo-
stat housing.
2. Remove the suction hoses between the turbocharger and
the air filter and between the turbocharger and the inlet mani-
fold.
3. Disconnect the turbocharger pressure and return oil pipes.
4. Remove the pipes to the thermostart fuel reservoir.
5. Remove the injector leak---off fuel pipes and the delivery
pipes. Remove the injectors. Fit blanking---off caps on all
open connections.
6. Remove the inlet and exhaust manifolds and the thermostat
housing.
Note!
It is possible to remove the cylinder head even thought
these parts are attached to the head.
7. Remove the valve cover and the breather hose.
8. Remove the rocker arm mechanism and the push rods.
9. Loosen all the cylinder head bolts firstby a 1/4 turn and then
remove them. Remove the cylinder head.
B. Removing valves
Ensure that valves which are to be re---used are marked, so
that they are fitted in their original locations.
9052 47200
23--- 1
9101 66200
1. Install the counter screw 9052 47200 for the valve spring in-
stalling tool in the rocker arm cover bolt. On the 320--- and
620/634---engines there is not a screw stud at the valves for
the centre cylinder. A bolt of suitable length should be used
instead.
2. Compress the valve springs using lever 9101 66200. Re-
move the valve cotters, spring guide and spring. Remove the
valves.
C. Checking cylinder head
1. Remove the soot from the exhaust ports, clean the sealing
surfaces and wash the cylinder head.
2. Check for cracks and other damage.
23--- 2
3. Check the flatness of the cylinder head by using a straight
edge. An uneven or warped surface should be surface
ground. The height of the cylinder head, after grinding, should
not be less than
104,00 mm
. The valve disc depth from the
cylinder head surface should be
0,60 mm
for the exhaust
valves and
0,70 mm
for the inlet valves.
9101 66000
23--- 3
4. Straighten and clean the injector location seat in the cylin-
der head with cutter 9101 66000.