Geely JL481Q, Manual, Page: 52 / 198

5. Check valve stem and valve guide
(1) Use inner dia. micrometer to measure inner diameter of
guide (Fig. 82).
Inner diameter of valve guide: 6.000-6.018mm;
(2) Use micrometer to measure diameter of valve stem(Fig. 83).
Diameter of valve stem:
Intake: 5.960-5.975mm;
Exhaust: 5.960-5.975mm.
(1) Standard oil clearance
Subtract measured valve stem diameter from measured
inner diameter of the valve guide to obtain:
Intake: 0.025-0.058mm;
Exhaust: 0.025-0.058mm.
(2) Max. oil clearance
Intake: 0.08mm
Exhaust: 0.10mm
If oil clearance is larger than the maximum value, replace valve
and valve guide.
Fig. 79 Check planeness on three planes of cylinder head
At cylinder block side
At intake manifold side
At exhaust manifold side
Fig. 80 Use dye penetrant to check
whether there is crack in cylinder head
Fig. 83 Measure diameter of valve stem at
position shown in the Fig.
Fig. 82 Check and measure inner diameter of valve guide
Fig. 81 Eliminate fuel combustion residue on valve
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