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Service Manual Mitsubishi SL-Series diesel engines
Version 08/2004
CYLINDER HEAD AND VALVE
MECHANISM
ENGLISH
INSPECTION
2. Clearance between valve stem and valve guide
The valve guide wears more rapidly at its both
ends than at any other parts. Measure the bore in
the guide for the stem at its ends with an inside
micrometer caliper to find the clearance between
the stem and guide. If the clearance exceeds the
limit, replace the guide or valve whichever is badly
worn.
Unit: mm (in.)
3. Valve guide replacement
1) Remove the guide from the cylinder head by
pushing it with a tool and an arbor press from
the bottom side of the head.
2) Install a new guide into the cylinder head by
pushing it with an arbor press from the upper
side of the head until the specified height to
the top of the guide is obtained.
3) Insert a new valve into the guide and make
sure the valve slides in the guide freely.
4) After the valve guide has been replaced,
check the valve contact with its seat.
Figure 69 Measuring valve guide
Inside micrometer
caliper
Item
Nominal
size
Standard Limit
Clearance
between
valve stem
and valve
guide
Inlet
valve
— 0.02 to
0.05
(0.000 8 to
0.002 0)
0.10
(0.003 9)
Exhaust
valve
— 0.05 to
0.085
(0.002 0 to
0.003 35)
0.15
(0.005 9)
Height to top of valve
guide
10
(0.39)
9.5 to 10.5
(0.374 to
0.413)
—
NOTE
Before measuring the valve guides, clear the guides
of lacquer and carbon.
Figure 70 Height to top of valve guide
Cylinder head
Valve guide
10 ± 0.5 mm
(0.39 ±
0.020 in.)
15 mm
(0.59 in.)