Man D 2866 LE 401, Repair Manual

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Replacing valve seat insert
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Removing valve seat insert
Note:
If the valve seat inserts have to be changed it is necessary to change the valve guides too, as other-
wise exact refacing of the valve seat inserts after the replacement cannot be guaranteed.
For these reasons previously mentioned the tool for removing and installing valve guides and valve
seat inserts was also designed in such a way that if this tool is used valve seat inserts can be re-
placed only together with the valve guides, i.e. valve guides, however, can also be changed alone.
Fig. 1
Use a valve seat machining tool (valve seat lathe)
to cut an approx. 3-4 mm wide groove in the valve
seat insert.
Insert internal puller into the groove and tighten it.
Fig. 2
Note:
To avoid damage to the cylinder head seal-
ing face, lay disc (2) or similar item under the
arms (3) of the support.
Turn threaded spindle (4) into the internal puller
(1), align the arms (3) of the support and pull out
valve seat insert by turning the nut (5).
Clean contact face of the seat insert in the cylinder
head.
Fig. 3
If no valve seat machining tool is available, the
following procedure may be followed:
D
Apply circular weld bead on the valve seat us-
ing an arc welding set (arrows),
D
then pull out valve seat insert.
D
Clean contact face of the seat insert in the
cylinder head.
2816
3581
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