Valve Guide Replacement - Honda NC700XA Service Manual

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Measure and record each valve guide I.D.
SERVICE LIMIT: 5.04 mm (0.198 in)
Subtract each valve stem O.D. from the corresponding
guide I.D. to obtain the stem-to-guide clearance.
SERVICE LIMITS:
IN: 0.075 mm (0.0030 in)
EX: 0.085 mm (0.0033 in)
If the stem-to-guide clearance is out of standard,
Reface the valve
determine if a new guide with standard dimensions
seats whenever the
would bring the clearance within tolerance. If so,
valve guides are
replace any guides as necessary and ream to fit.
replaced (page 10-
If the stem-to-guide clearance exceeds the service limit
22).
with the new guides, replace the valves and guides.

VALVE GUIDE REPLACEMENT

Chill the replacement valve guides in the freezer
section of a refrigerator for about an hour.
Heat the cylinder head to 100 – 150°C (212 – 302°F)
Do not use a torch
with a hot plate or oven.
to heat the cylinder
To avoid burns, wear heavy gloves when handling the
head; it may cause
heated cylinder head.
warping.
Support the cylinder head and drive out the valve
guides from combustion chamber side of the cylinder
head.
TOOL:
Valve guide driver [1]
Drive in the valve guides to the specified depth from the
top of the cylinder head.
SPECIFIED DEPTH:
IN: 17.7 – 18.0 mm (0.70 – 0.71 in)
EX: 19.6 – 19.9 mm (0.77 – 0.78 in)
TOOL:
Valve guide driver [1]
Let the cylinder head cool to room temperature.
Ream new valve guides after installation.
Use cutting oil on
the reamer during
Insert the reamer [1] from the combustion chamber side
this operation.
of the cylinder head and always rotate the reamer
clockwise.
TOOL:
Valve guide reamer, 5.010 mm
Clean the cylinder head thoroughly to remove any
metal particles.
Reface the valve seat (page 10-22).
07942-8920000
07743-0020000
[1]
07984-MA60001
CYLINDER HEAD/VALVES
10-21
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