Section 2 Inspection And Maintanence Of Engine - Baja WD250U Service Manual

Section 2 Inspection and Maintenance of Engine
1. Cylinder cover
1) Clean
• Carbon deposit
Use circular scraper (1)
CAUTION:
Please do not use sharp tool to avoid scraping
• Nut of spark plug
• Valve seat ring
• Bottom face of cylinder
2) Measure
• Flatness of cylinder cover bottom face
Recorrect the bottom face or replace if
unqualified
Flatness of cylinder bottom face is less than
0.10mm (0.004in)
2. Intake and exhaust valve
1) Check
• Valve surface
• Valve rod end
Replace it if it is worn, exfoliation corroded or
unqualified
Min thickness (working limit)
(a) 0.8mm (0.031in)
Slope
(b) 0.5mm(0.020in)
Min length (working limit)
(c) 4.0mm(0.157in)
2) Check
• Valve rod end (1)
Replace the valve, valve guide pipe and valve
rod oil seal if it is mushroom-shaped or its
diameter is bigger than other rod diameter.
CAUTION:
Remove the deformation of valve rod end (1)
by polishing the valve end with oilstone.
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