(d)
Install the igniter plug boss and guide assembly, spacer(s) and keywasher (Fig. 801). 1) Tighten the igniter plug boss and guide assembly to 375-440
pound-inches (42.4-49.7 newton-meters). 2) Safety the igniter plug boss and guide assembly with lockwire or safety cable and safety cable ferrule.
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(e) Report the engine serial number, igniter position number, engine time and cycles and the date that you installed the igniter plug guide and boss assembly to your local Pratt & Whitney representative.
S 218-017-N00
(5) Do the steps that follow until the time the diffuser case is disassembled and PW SB 72-601 is incorporated:
(a)
Examine the igniter plug guide and boss assembly for wear before or at each 7000 hours engine time.
(b)
Report the engine time and cycles and detailed condition of the parts to your local Pratt & Whitney representative.
NOTE: A monthly report of the condition of the parts is
____
optional.
S 908-008-N00
(6) Do the steps that follow at the subsequent time the diffuser case is disassembled:
(a)
Replace the igniter plug guide and boss assembly as specified in PW SB 72-601.
(b)
Report the engine serial number, igniter position number, engine time and cycles and the date that the igniter plug guide and boss assembly is replaced to your local Pratt & Whitney representative.
(c)
Report the detailed condition of the parts to your local Pratt & Whitney representative.
(d)
Give the igniter plug boss and guide assembly to your local Pratt & Whitney representative when PW SB 72-601 is incorporated.
S 418-009-N00
(7) Install the igniter plug (AMM 74-21-02/401).
F. Return the Aircraft to Its Usual Condition
S 418-010-N00
(1)
Close the right core cowl panel (AMM 71-11-06/201).
S 448-015-N00
(2)
Do the activation procedure for the thrust reverser
(AMM 78-31-00/201).
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ENGINE IGNITION CONTROL - DESCRIPTION AND OPERATION
___________________________________________________
1. General
_______
A. The ignition system is controlled by the engine ignition control module, found on the P5 overhead panel, during flight and ground starts.
B. Ignition control for normal operation is supplied by the engine start switch, the ignition switches, and the fuel control switch. With these switches positioned correctly, electrical power is supplied to the ignition exciters. The ignition exciters convert the input power into a high energy pulsating spark across the igniter plug gap. The spark initiates or sustains combustion. Power for ignition control is supplied from the battery bus for the circuit breakers on the P6 panel for the main power distribution.
C. Each engine has a dual ignition system. The ignition systems are powered by independent primary ac buses. The ignition circuit automatically switches to standby power if normal electrical power is lost.
D. To energize ignition exciter, the fuel control switch must be moved from the CUTOFF position to the RUN position.
2. Engine Ignition Control Module (Fig. 1)
______________________________
A. The engine ignition control module includes four engine start switches, a selector for the automatic ignition control, a continuous ignition switch, and a standby ignition selector.
B. There is one engine start switch for each engine. All other engine ignition control is done simultaneously for all engines depending on switch/selector position.
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