Spark Plug Gap Adjustment - Piper APACHE PA-23-235 Service Manual

tilating air passages
of the heater.
385
Should this happen, remove the gasket
with a wire hook.
0.050 to 0.060 inch BEND TO ADJUST
b. Inspection and Servicing:
1. If the spark plug appears to CENTER
ELECTRODE
be in good condition,
except for a mild
GROUND ELECTRODE
coating of oxide on the porcelain and
electrodes,
it may be cleaned and re-
used. Cleaning is accomplished on a
conventional airplane type spark plug
cleaner, except that it will be necessary
to use two or more adapters in order
to raise the long extension of the plug
far enough out of the cleaner nozzle
opening to provide an effective job. Plug
the ceramic insert cavity at the ter- Figure 13-28. Spark Plug Gap
minal-end of the plug with a piece of Adjustment
paper or cloth to keep out any of the
cleaning sand. Wipe this cavity out thoroughly with a cloth, wet with carbon tet-
rachloride.
If, after cleaning, the spark plug porcelain is white, and the elec-
trodes are not eroded, re-gap the spark plug by carefully bending the ground
electrode until a 0.055 inch feeler gauge can be inserted between the end of the center
electrode and the ground electrode.
NOTE
If the spark plug fails to clean up properly and/or if
electrodes
are badly eroded, it should be replaced.
c. Installation:
(Refer to Figure 13-28.)
1. If a new spark plug is being installed, be sure to measure the gap which
should be between 0.051 and 0.060-inches.
Do not bend the center electrode.
NOTE
The spark plug can be checked visually for sparking
across the gap prior to installing the plug as follows:
Disconnect the wire from the No. 3 terminal on the
heater wiring side of the terminal strip to de-energize
the fuel solenoid valve. Connect the high-voltage lead
temporarily and lay the spark plug on the heater jacket.
HEATING AND VENTILATING SYSTEM
Reissued: 2/18/81
PIPER AZTEC SERVICE MANUAL
5E14