Piper Cherokee Six Service Manual page 452

PIPER CHEROKEE SIX SERVICE MANUAL
234
Figure 7A-53. Removing Spark Plug Frozen to Bushing
not apply to plug removal and sufficient torque must be used to unscrew the plug. The
higher torque in removal is not as detrimental as in installation, since it cannot stretch the
threaded section. It does, however, impose a shearing load on this section and may, if
sufficiently severe, produce a failure in this location.
NOTE
Torque indicating handle should not be used for spark plug
removal because of the greater torque requirement.
c. Place spark plugs in a tray that will identify their position in the engine as soon as
they are removed.
NOTE
Spark plugs should not be used if they have been dropped.
d. Removal of seized spark plugs in the cylinder may be accomplished by application
of liquid carbon dioxide by a conical metal funnel adapter with a hole at the apex just large
enough to accommodate the funnel of a CO2 bottle. (Refer to Figure 7A-53.) When a seized
spark plug cannot be removed by normal means, the funnel adapter is placed over and
around the spark plug. Place the funnel of the CO2 bottle inside the funnel adapter and
release the carbon dioxide to chill and contract the spark plug. Break the spark plug loose
with a wrench. A warm cylinder head at the time the carbon dioxide is applied will aid in
the removal of an excessively seized plug.
e. Do not allow foreign objects to enter the spark plug hole.
POWER PLANT
Added: 7/28/75
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