Inspection; Cylinder Head - Yamaha Motor 20C Manuel D'entretien

POWR

INSPECTION

G61000-0*
INSPECTION

CYLINDER HEAD

Cleaning
1) Using a gasket scraper, remove all traces of
gasket material from the cylinder head.
2) Using a round scraper, remove carbon deposits
from the combustion chamber.
cC
Do not scratch the surfaces of the cylinder head
and combustion chamber.
3) Using a soft brush, clean the water jacket.
Inspection
1) Using a precision straight-edge and feeler
gauge, measure the surface contacting the
cylinder block for warping.
Maximum allowable warp:
0.10 mm (0.0039 in)
If the degree of warping exceeds this specification,
re-surface the cylinder-head as follows:
Place 400 – 600 grit wet-or-dry paper on the sur-
face-plate, and resurface the cylinder-head using a
figure-eight sanding pattern.
5-15
E