Igniter Plugs - Piper Malibu Meridian PA-46-500TP Airplane Maintenance Manual

1.

Igniter Plugs

The spark igniters are located at 4 and 9 o'clock positions on gas generator case, adjacent to fuel
manifold. Observe all safety precautions when working on ignition system. See also Pratt & Whitney
Canada's Maintenance Manual - Turboprop Gas Turbine Engine Model(s) PT6A-38/-40/-41/-42/-42A -
Part No. (P/N) 3021442, 74-20-00.
WARNING: RESIDUAL VOLTAGE IN THE EXCITER CAN BE VERY HIGH. ENSURE IGNITION IS OFF
AND SYSTEM IS INOPERATIVE FOR AT LEAST SIX (6) MINUTES BEFORE REMOVING
COMPONENTS. ALWAYS USE INSULATED TOOLS. REMOVE COUPLING NUTS AT
EXCITER END FIRST. DO NOT TOUCH OUTPUT CONNECTORS OR COUPLING NUTS
WITH BARE HANDS.
A. Removal
(1) Remove power from ignition system.
(2) Disconnect coupling nut from igniter.
CAUTION: WHEN UNSCREWING COUPLING NUTS, DO NOT ALLOW BRAIDING,
(3) Remove igniter plug and copper gasket from gas generator case.
B. Installation
CAUTION: USE ONLY P&WC-APPROVED ANTI-SEIZE COMPOUND (I.E. - NEVER-SEEZ OR
SILVER GOOP) DURING REINSTALLATION. TAKE CARE TO APPLY COMPOUND
ONLY TO IGNITER THREADS OR BOSS THREADS.
(1) Install new copper gasket and igniter into gas generator case. Tighten igniter and torque to 300
inch-pounds. Loosen to 0 inch-pounds and retorque to 300-360 inch-pounds.
CAUTION: DO NOT ALLOW IGNITION CABLE BRAIDING, FERRULE OR IGNITER PLUG
(2) Reconnect ignition cable to igniter plug. Tighten coupling nuts fingertight plus 45 degrees.
C. Cleaning and Inspection
(1) Cap cable end of igniter plug to prevent foreign material from entering during cleaning.
NOTE: Never clean electrode end (firing) of igniter. Do not remove carbon from electrode or
annular gap area as carbon deposits in gap area aid igniter operation.
(2) Using felt swab soaked in solvent (i.e. - Varsol or isopropyl alcohol); clean inside surface of
terminal well.
(3) Dry igniter with dry, compressed air.
CAUTION: IF IGNITER PLUG IS DROPPED, INTERNAL DAMAGE, NOT DETECTABLE BY
(4) After cleaning igniter, inspect electrode end for erosion limits. (Refer to Chart 1.)
CAUTION: SHOULD AN IGNITER PLUG BE DROPPED, INTERNAL DAMAGE, POSSIBLE
CAUTION: IF IGNITER PLUG IS DROPPED, INTERNAL DAMAGE, NOT DETECTABLE BY
7G13
PIPER AIRCRAFT, INC.
PA-46-500TP, MALIBU MERIDIAN
MAINTENANCE MANUAL
DISTRIBUTION
FERRULES, OR IGNITER PLUG TO TURN AT SAME TIME.
TO TURN WHEN SCREWING ON COUPLING NUT.
TEST, CAN OCCUR AND IGNITER PLUG MUST BE REPLACED.
NOT DETECTABLE BY TEST, CAN OCCUR. RECOMMENDATION IS TO
REPLACE THE IGNITER PLUG.
TEST, CAN OCCUR, AND IGNITER PLUG MUST BE REPLACED.
74-20-00
Apr 15/07
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