Valve And Rocker Arm - Kubota Z400-B Handbuch

[2] VALVE AND ROCKER ARM
Valve Clearance
1. Loosen the lock nut and the adjusting screw on the rocker
arm.
2. Turn the adjusting screw to adjust the valve clearance at
the top dead center (T.D.C.) during compression stroke of
the piston.
3. Tighten the lock nut and check the valve clearance again
after several turns of the flywheel.
• NOTE:
• To get T.D.C. of piston, find its "TC" mark on the fly ­
wheel and align it with the punch mark line on the rear
end plate (See photo).
0.15
to
0.18
mm
Factory specification
0.0059 to 0.0071 in.
Valve Stem Clearance
1. Remove the carbon from the valve guide.
2. Make sure that the valve stem is straight and insert the
valve into the valve guide.
3. Set the dial indicator with its tip on the stem near the end
of the valve guide.
4. Measure the clearance, moving the valve sideways.
If the measurement exceeds the allowable limit, replace
0.1 mm
0.004 in.
6.010 to 6.025 mm
the valve guide or the valve.
Factory
Clearance between specification
valve stem and valve
Allowable
guide
limit
OJ {J.'IFlII,8
V I
'd b i D • Factory
a~e 9UI~:r~e
. . • specification
Factory
specification
stem O.D. Allowable
limit
1.
Press out the valve guide toward the head cover using a
.ReplacinjlValve Guide
(When removing)
valve guide replacing tool
(When installing)
1. Clean the valve guide bore and apply engine oil to the
bore, before installing the valve guide.
2. Press in the valve guide until its end comes flush with the
cylinder head surface using a valve guide replacing tool.
• IMPORTANT:
• Ream precisely the bore to the specified dimension after
installing the valve guide.
(fli!ij.'(){ii
Valve guide bore
0.23661
to
0.23721
in.
5.969
to
5.980
mm
0.23496
to
0.23543
in.
5.93
mm
0.2335
in.
S-87