1
Valve stem cap (12 rqr)
2
Valve spring lock retainer (24 rqr)
3
4
Valve spring retainer (12 rqr)
5
Valve spring (12 rqr)
6
Tappet (12 rqr)
7
Adjusting screw (12 rqr)
8
9
Intake valve (6 rqr)
10
Intake valve guide (6 rqr)
11
Valve tappet guide bushing (12 rqr)
12
Valve seat insert (6 rqr)
Figure 17. -Continued.
b. Inspection and Repair.
(1) Inspect the pistons for wear, galling,
scoring, burned condition, and out-of-
round. The piston diameter is 4.288
inches minimum and '4.241 inches
maximum.
The wing groove width
diameter is 0.097 inch minimum and
0.098 maximum.
Replace defective
pistons.
(2) Inspect piston for cylinder bore fit and
clearance. Pistons should be fitted with
the cylinder bore of the block at room
temperature, 680-75F. Check the piston
fit in the cylinder bore using a strip of
0.004 inch feeler gage stock, the feeler
being attached to a small scale of
approximately 15 pounds capacity. The
correct piston fit is obtained when the
feeler gage can be withdrawn from
between the piston and cylinder wall with
a pull of 5-10 pounds on the scale. The
feeler gage must be inserted between the
piston and cylinder wall midway between
the piston pin bosses, where the diameter
of the. piston is the greatest. Check the
fit of the piston when it is 2 inches down in
the cylinder bore in an inverted position.
The correct piston to cylinder wall
clearance is 0.004 inch. Piston clearance
should be in accordance with specification
shown in the limits and clearance table.
Figure 17. -Crane engine valve assemblies, exploded
view.
TAGO 5030A
55