Man D 2840 LE 301, Repair Manual

Page: 119 / 194

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Checking the valve timing
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Note:
Unsynchronised valve timing can cause
severe engine damage.
For this reason, following engine faults that
can cause twisting of the shrunk-on cam-
shaft toothed wheel, the correct seating
must be checked by checking the valve
timing.
This check is also recommended after the
camshaft is fitted.
Fig. 1
Remove the cylinder head cover from the 1st cylin-
der.
Set the valve clearance of the 1st cylinder cor-
rectly.
Fig. 2
Turn the engine using the barring gear until the
valves of the 1st cylinder overlap.
Turn the engine back to approx. 50
_
before “TDC”,
then turn forwards to 30
_
before “TDC” again.
− Observe graduation on flywheel −
Fig. 3
Place the dial gauge with approx. 2 mm initial ten-
sion on the valve spring retainer of the exhaust
valve on cylinder no. 1 and set to “0”.
Turn engine in running direction through 180
_
.
− Exhaust valve fully closed −
Read the stroke of the valve on the dial gauge.
The valve stroke must be between 4.5 and
5.3 mm.