Yamaha DT200L 1984-1988 Service Manual page 69

INSPECTION AND REPAIR
ENG
INSPECTION AND REPAIR
Cylinder Head
1. Remove:
• Carbon deposits
Use a rounded scraper CD.
NOTE:
Take care to avoid damaging the spark plug
threads. Do not use a sharp instrument. Avoid
scratching the aluminum.
2. Inspect:
• Cylinder head water jacket Crust of
minerals/ Rust-- Remove.
• Cylinder head warpage out of specifica-
tion^-Re-surface.
Warpage Measurement and Re-surface-
ment Steps:
• Attach a straight edge and a thickness
gauge on the cylinder head.
• Measure the warpage limit.
Warpage Limit:
0. 03 mm (0. 0012 in)
• If the warpage is out of specification, re-
surface the cylinder head.
• Place a 400-600 grit wet sandpaper on
the surface plate, and re-surface the head
using a figure-eight sanding pattern.
NOTE:
Rotate the head several times to avoid remov-
Ing too much material from on side.
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