TM 9-6115-604-34
NAVFAC P-8-633-34
Table 9-1. General Defect Definitions (Continued)
TERM
DEFINITION
PROBABLE CAUSE
Galling
A transfer of metal from one surface to
Severe chafing action; metal particles from
another.
relative parts are embedded in opposite surfaces.
Lack of lubrication, improper -
clearances.
Grooving
Smooth, rounded furrow, such as score
Concentrated wear, parts out of alignment,
marks whose sharp edges have been pol-
lack of lubrication.
ished off.
Nick
A sharp indention.
Careless handling, or break-up of compo-
nents during operation
Peening
Deformation of the surface.
Repeated impact of foreign objects; failure of
components during operation.
Pitting
Small cavities on a surface.
Improper clearance or:
(Mechanical) Pressure of foreign material.
(Corrosive) Breakdown of surface by
chemical action
Scoring
Deep scratches.
Presence of foreign particles between loaded
surfaces having relative motion. Improper
lubrication.
Scratches
Narrow, shallow marks on surfaces.
Careless handling, foreign particles in engine during
operation. Improper lubrication.
SECTION II. MAINTENANCE OF CYLINDER HEAD ASSEMBLIES
9-3.
GENERAL. The engine intake and exhaust is controlled by four valves for each cylinder, contained in 12
individual cylinder heads. Two camshafts, one located in each cylinder bank control the opening and dosing of the
valves. Roller-type cam followers transmit the motion caused by the camshaft lobes to three push rods. Each push rod
activates an intake, exhaust, and injector rocker lever located in the rocker lever housing bolted to the top of each
cylinder head. The intake and exhaust valve crossheads, located in the cylinder heads, are moved by the rocker levers
and each crosshead opens two intake or two exhaust valves. During the dosing cycle, the valves are dosed by springs
keyed to the valve stems. Since 12 individual cylinder heads are used on the KTA 2300 engine, one cylinder head, or all
cylinder heads may be replaced or repaired at one time, depending on the job to be accomplished. The removal and
installation instructions cover the replacement of all cylinder heads. If it is desirable to replace one particular cylinder
head. lt may be possible to omit some of the steps. The technician will make this decision based on the job to be
accomplished, and the individual cylinder head or heads to be replaced.
9-4.
INSPECTION OF CYLINDER HEAD ASSEMBLIES. (See F igure 9-1 and Figure 9-2.)
a.
Visually examine the area around the cylinder head capscrews (11, Figure 9-1), and pipe plugs (19 and 20)
for evidence of coolant leakage.
b.
Check all expansion plugs (21 and 22) for evidence of coolant leakage. Check expansion plugs for
soundness by tapping lightly with a punch. Expansion plugs which penetrate easily shall be replaced in
accordance with paragraph 2-10.
c.
Inspect the head gasket area for signs of coolant leakage.
d.
Remove the valve covers in accordance with paragraph 9-5, step h.
e.
Inspect the rocker arms (12, 13, and 14, Figure 9-2) and crossheads (8, Figure 9-1) for breakage or outward
signs of cracking.
f.
Inspect the valve springs (3) for breakage.
g.
Inspect the valve guides (25) for breakage or outward signs of cracking.
9-3
