Figure 3-29. Valve seat-sectional view

TM 9-2815-213-34

NOTE

If nylok capscrew breakaway torque is

less than 15 inch pounds, replace

capscrews.

Figure 3-29. Valve seat-sectional view.

(a) Install injector sleeve holder (15, fig. B-28) on a

scrap injector and cup assembly into each injector

sleeve. Tighten sleeve holders to 10/12 foot-pounds

torque or injector capscrews to 30/35 foot-pounds torque

as shown in figure 3-30.

(b) Using water heated to 175/200 degrees

Figure 3-31. Injector tip protrusion measurement.

Fahrenheit, test cylinder head for leaks at 35/85 pounds

pressure.

Valves.

(1) Inspect valve heads for pitted, cupped,

of water leaks. Mark sleeves for replacement that

cracked, or excessively worn condition. Check valve

evidence leakage. If cylinder head shows leakage,

head rim thickness (fig. 3-32) and replace valve if less

replace head.

than 1/16 inch.

(d) Open water outlet valve to check for free water

(2) Inspect valve stems for scored, cracked or

circulation through cylinder head.

excessively worn condition. If stems are worn beyond

(2) Inspect injector sleeves for scratches on cup

0.4490 inch replace valve.

seat area and for continuous contact by using Prussian

(3) Inspect collet recesses (fig. 3-32) for

Blue. Mark sleeve that is scratched on does not show

serviceability.

continuous seat contact, of at least 0.060 inch wide, for

f. Crosshead Giudes (fig. 3-33).

replacement.

(1) Check crosshead guides with a square. They

(3) Check injector tip protrusion by installing

must be perpendicular at four right angles with the

injector assembly and torquing to 30/35 footpounds. If

cylinder head.

injector protrusion exceeds 0.125 inch mark sleeve for

(2) Measure outside diameter of crosshead

replacement (fig. 3-31).

guides using a micrometer. Guides must measure

0.4322 inch minimum. Discard if worn beyond that limit.

(3) Measure crosshead protrusion above block to

2.090/2.110 inches. Discard guides not within these

tolerances.

g. Valve Guides (fig. 3-34).

(1) Adjust a small bore gage with a micrometer

at 0.0002 inch above worn limit, and use as "No-Go"

gage.

(2) Mieasure the hole at several points crosswise

and endwise of the head.

(3) Mark valve guide for replacement if worn

larger than 0.4545 inch inside diameter.

(4) Inspect sharp edge of guides for chips,

cracks and burrs. If damaged, mark for replacement.

Figure 3-30. Injector sleeve holder installation.

3-17