landrover Workshop Repair Guides

Land Rover Engine Overhaul Manual | V8 Workshop Service Manuals

Valves - lapping-in > < Valve seat inserts - inspection
Page 40
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ENGINE

OVERHAUL

11

Valve seat inserts - renew

NOTE: Service valve seat inserts are
available 0.025 mm (0.001 in) oversize on
outside diameter to ensure interference fit.

1. Remove worn valve seats.

CAUTION: Take care not to damage
counterbore in cylinder head.

2. Heat cylinder head evenly to approximately

120

°

C (250

°

F).

WARNING: Handle hot cylinder head with
care.

3. Using a suitable mandrel, press new insert fully

into counterbore.

4. Allow cylinder head to air cool.

Valve seats and seat inserts - refacing

CAUTION: Renew worn valve guides and
seat inserts before lapping valves to their
seats.

1. Check condition of valve seats and valves that

are to be re-used.

2. Remove carbon from valve seats.

3. Reface valves as necessary. If a valve has to

be ground to a knife-edge to obtain a true seat,
fit a new valve.
Valve seating face angle = 45

°

Valves - lapping-in > < Valve seat inserts - inspection