Yamaha XVS6501997, Руководство по обслуживанию

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4-12
CYLINDER HEADS
ENG
NOTE:
NOTE:
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NOTE:
6. Remove:
S
Cylinder head
D
Loosen the bolts and nuts in the proper se-
quence.
D
Follow the numerical order shown in the il-
lustration. Loosen each bolt 1 / 4 of a turn at a
time until all of the bolts are loose.
Front cylinder head
When removing the front cylinder head cam-
shafts, repeat the rear cylinder head camshafts
removal procedures. However, note the follow-
ing points.
1. Align:
S
“I” mark
(with the stationary pointer)
Removal steps:
D
Turn the crankshaft clockwise 290
_
.
D
Align the “I” mark a with the stationary point-
er b on the crankcase cover (left) when the
front piston is at TDC on the compression
stroke.
D
When the “I” mark is aligned with the station-
ary pointer the punch mark
c on the cam-
shaft sprocket should be aligned with the sta-
tionary pointer
d on the cylinder head.
D
The front piston is at TDC on the compres-
sion stroke when there is clearance at both of
the rocker arms. If there is no clearance then
turn the crankshaft clockwise one full turn.
D
Check that the front piston is at TDC in the
compression stroke.
CYLINDER HEAD INSPECTION
1. Eliminate:
S
Carbon deposits (from the combustion
chambers)
Use a rounded scraper.
Do not use a sharp instrument to avoid damag-
ing or scratching:
D
Spark plug threads
D
Valve seats
2. Inspect:
S
Cylinder heads
Scratches / damage
Replace.