Valve Seat, Change; Rocker Arm Mechanism, Overhaul - Volvo Penta D1-13 Workshop Manual

P0008007
P0008014
47701798 05-2013 © AB VOLVO PENTA
A

Valve Seat, Change

The valve seats should be changed when distance "A",
measured with a new valve exceeds 1.8 mm (0.071").
1 Remove the old valve seat by heating it with a gas
torch between 600–700 °C (1112– 1292 °F) diag-
onally across the seat.
Let the cylinder heat cool for 3-5 min in the air. Then
carefully tap the seat out with a mandrel (check that
the cylinder head is not damaged).
The valve seat can also be milled out (check that
the cylinder head is not damaged).
2 Carefully clean the valve seat bed in the cylinder
head. Check the cylinder head for cracks.
3 Cool the new valve seat with carbon dioxide snow
etc. to minus 60–70 °C (140–158 °F) and possibly
heat the cylinder head to 60–100 °C (140–212 °F).
4 Seat the seat into the cylinder head. Use a hydraulic
press and a suitable mandrel.
5 Machine the seats to the correct angle and width.

Rocker Arm Mechanism, Overhaul

1 Remove the plug at the front of the rocker arm shaft.
If the shaft has a stop screw, it must be removed
before the shaft is pulled 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 micro-
meter.
5 Check that the rocker arm bearing surfaces are not
worn oval. Check the clearance between rocker
arm and shaft. Check that the spherical part of the
adjustment screw is not deformed or worn. The
threads on the pin and lock nut must be undam-
aged. The lock nut must be in good condition.
6 Oil the rocker arm shaft and disassemble the other
components.
21-4 Valve Mechanism
75