TM 53740-214-14
Table 5-3. Direct and General Support Maintenance Troubleshooting (Continued)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
ENGINE SKIPS AT HIGH SPEED (Continued)
Figure 5-174. Spark Plug Defects
(2)
Electrodes worn so thin they cannot be regapped.
(3)
Oil fouling, soft, wet, oily covering the insulator and the plug nose. If there is oil fouling, notify
your supervisor.
(4)
Build-up of deposits between insulator and the plug shell.
(5)
Broken insulator or bent electrode.
NOTE
If the spark plug must be replaced, set the gap at 0.025 inches (0.64 mm).
Oil fouling is a sign of internal engine damage.
c.
Check the spark plug gap.
(1)
Reset the gap at 0.025 inches (0.64 mm) if necessary and go to Step 1d.
(2)
If the gap is ok, go to Step 1d.
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