TM 10-4320-307-24
4-11
INJECTOR REPAIR (CONT).
11.
Inspect cup retainer as follows:
a.
Inspect threads for damage.
b.
Check outside cone area for nicks and burrs that could prevent proper seating with the sleeve in the head.
c.
Inspect inside of cone area on cup seating ledge for nicks or burrs that could prevent the cup from seating.
12.
Inspect compression springs as follows:
a.
Check spring for excessive wear or mutilation.
b.
Test spring tension on spring tester. This spring tester is capable of very accurate measurements of spring
lengths and applied load by means of standards and dial indicator gauge.
c.
If injector springs compress to the given dimensions, less than the minimum acceptable worn limit, the spring
must be discarded.
Load Required to Compress Spring to Length
Approx. Free
Length
Minimum
Maximum
Length Inch (mm)
Inch (mm)
lb. (kg)
lb. (kg)
Small Compres-
1.490
1.055
85.70
95.70
sion Spring
(37.8460)
(26.80)
(38.8)
(43.4)
Large Compres-
1.506
0.930
110.0
126.0
sion Spring
(38.2524)
(23.62)
(49.8)
(57.1)
d.
Check squareness of spring used in top stop injector.
(1) Place spring in V-block and stand assembly up on a flat surface.
(2) Maintain contact between coils of the spring and the V-block and baseplate while rotating the spring.
Measure flatness of the ground ends (approximately 270 degrees) with dial indicator.
(3) Turn spring over in V-block and check opposite end using the procedure as outlined in step (2).
NOTE
The amount must not exceed 0.016 inch (0.41 mm) on each end. Springs which
do not meet this standard must be discarded.
13.
Inspect spring retainer. Replace retainer if it is worn more than 0.003 inch (0.076 mm) deep.
14.
Inspect plunger links for wear. If wear can be seen or felt. it shall be considered excessive and link should be
replaced.
15.
Inspect filter screen for clogging or deterioration of screen. Replace filter screen if it is worn through or torn.
16.
Inspect roll pins in injector adapter for damage. Replace roll pins if damaged.
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