Service manual

ENGINE INSPECTION
INSPECTING .THE CYLINDER HEAD
1. Visual Inspection. Check the cylinder head for cracks or
any other damage and,
if necessary, repair or replace it.
2. Distortion Inspection. Measure the cylinder head sur-
face distortion with a straight edge and the thickness
gauge. Take 6 measuring positions as shown in the dia-
gram.
If the distortion exceeds permissible limit, replace
the cylinder head. (The head has no allowance for plan-
ing and must be replaced, not renewed.)
Position Cylinder Head Distortion Limit
1,2 0.004 in (0.10mm)
ii, 4, 5, 6 0.010 in (0.25mm)
REMOVE LOCATING DOWELS
BEFORE USING STRAIGHT-EDGE
FEELER GAUGE
DISTORTION INSPECTION
3
4--~~~~~~~~~~~~~H-
5 -~+-!,:=~~_~~~o......E~~~~:-- 5
6 6
1
2
3.
Insert Inspection. Check for cracks or damage on the
insert and,
if detected, replace it.
4.
Insert Replacement. To remove the insert, place a
suitable drift into the glow plug hole, then tap the drift
with a hammer.
To install, set the insert in position and
insert the welch washer into the insert guide hole. Secure
the welch washer by tapping the raised center
of the
welch washer.
a
Use a new welch washer.
h. Insert the welch washer so that its convex surface is
toward the cylinder head gasket.
c. After installation, check to see
if the insert is com-
pletely fixed in place.
SUITABLE PUNCH ~
VALVE SPRING
REMOVING THE
INSERT
1. Free Length Check. Measure the free length pf the valve
spring and
if free length is less than the limit, replace it.
Valve Spring Inner 1.654 in (42mm)
Outer2.083 in (52.9mm)
VALVE
SPRING __
2. Squareness Check. Check the squareness of the valve
spring and,
if it is more than the limit, replace the spring.
Squareness Limit Inner 0.049 in (1.25mm)
Outer 0.054 in (1.37mm)
3. Fitting Pressure Check. Check the valve spring fitting
pressure with a valve spring tester and,
if the pressure is
less than the limit, replace the spring.
90° TEST ANGLE
Engines & Generators
14