Volvo Penta D2-55, Workshop Manual

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33
Group 21 Short block
Overhauling the rocker arm
mechanism
Special tools: 999 6400
1. Remove the screw from the front edge of the
rocker arm shaft.
Screw an M8 bolt into the rocker arm shaft. Grab
the bolt with i.e. a pair of pliers and pull the rocker
arm shaft out.
2. Disassemble the rocker arm mechanism. Remove
the rocker arms, springs and washers.
3. Clean the components. Be especially careful with
the rocker arm shaft oil channels and the oil holes
in the rocker arms
4. Check the wear of the rocker arm shaft with a mi-
crometer.
5. Check that the rocker arm bearing surface is not
worn oval. Check the clearance between rocker
arm and shaft.
Check that the spherical section of the adjust-
ment screw is not deformed or worn. The threads
on the pin and lock nut should be undamaged.
The lock nut should be in good condition.
6. Oil the rocker arm shaft and assemble the various
parts.
Assembly of cylinder head
Special tools: 885 023, 885 498
1. Press the new valve stem seals onto the valve
guides.
Note. The seals for the inlet and exhaust valve
guides are different. The inlet valve seal has a silver
spring while the exhaust valve seal’s spring is black.
2. The valves must be installed in the correct order.
Oil the valve stems and install one valve (1) in it’s
guide. Place the valve spring (2) and spring wash-
er (3) in place and compress the spring with valve
spring compressor 885 023 and pressure foot 885
498. Install the valve cotters (4).
Be careful when mounting the valves and when
compressing the springs, so that the valve stem
seals are not damaged. Check that the valve cot-
ters are properly seated.
3. Install the valve caps (5) once all the valves are
fitted.
4. Mount new core plugs if these have been re-
moved.
5. Install the glow plugs. Tightening torque, please re-
fer to “Technical Data”. Install the power rail.
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