Mitsubishi S3Q2, Руководство по обслуживанию

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INSPECTION AND REPAIR OF BASIC ENGINE
6-2
1. Inspecting and repairing cylinder head and valve mechanism
1.1 Measuring distortion of the bottom surface
of the cylinder head
With a straight edge placed on the bottom face of the
cylinder head, measure the bottom face distortion using a
feeler gauge. If the measurement exceeds the limit, grind the
bottom face using a surface grinder.
Note: Do not grind the surfaces more than 0.2 mm [0.008
in.] in total (cylinder head bottom surface plus
crankcase top surface).
Measuring distortion of the bottom surface of the
cylinder head
1.2 Measuring clearance between rocker arm
and rocker shaft
Measure the inside diameter of the rocker arm and outside
diameter of the rocker shaft.
Replace the rocker arm or rocker shaft if the clearance
exceeds the limit.
Measuring rocker arm inside diameter and rocker shaft
outside diameter
1.3 Measuring perpendicularity and free length
of valve spring
Measure the perpendicularity and free length of the valve
spring. If the limit is exceeded, replace the valve spring with
a new one.
Squareness and free length of spring
Item Standard Limit
Bottom surface
distortion 0.05 mm
[0.0020 in.] or less
0.20 mm
[0.0079 in.]
Item Nominal Standard Limit
Rocker arm
inside
diameter
ø 19 mm
[0.75 in.]
19.01 to 19.03 mm
[0.7484 to 0.7492 in.]
-
Rocker shaft
diameter ø 19 mm
[0.75 in.]
18.98 to 19.00 mm
[0.7472 to 0.7480 in.]
-
Clearance
between
rocker arm
and shaft
-
0.01 to 0.05 mm
[0.0004 to 0.0020 in.]
0.07 mm
[0.0028 in.]
Measuring
directions
Measuring
points
Item Standard Limit
Free length
48.85 mm
[1.9232 in.]
47.60 mm
[1.8740 in.]
Perpendicularity
θ
= 1.5° or less
Δ
(gap) = 1.3 mm
[0.051 in.] or less
Lf = 48.85 mm
[1.9232 in.]
Δ
= 1.5 mm
[0.059 in.]
over entire
length
Set length/set
force
43 mm [1.69 in.]/
176 to 196 N
{18 to 20 kgf}
[130 to 145 lbf]
43 mm
[1.69 in.]/
147 N
{15 kgf}
[108 lbf]
ٌ
Lf
ǰ
Free length
Spring perpendicularity (gap)