Technical data

13773-001
74-30
Page 1
SWITCHING
1. DESCRIPTION
This section describes that portion of the ignition system which provides a means of rendering the ignition
electrical power supply inoperative. This includes the ignition switch.
2. MAINTENANCE PRACTICES
A. Ignition Switch (See Figure 74-301)
(1) Removal - Ignition Switch
(a) Turn ignition switch to the OFF position.
(b) Remove engine cowling. (Refer to 71-10)
(c) Disconnect battery. (Refer to 24-30)
(d) Remove retaining nut securing ignition switch to bolster panel, remove placard plate, and
pull switch from forward side of bolster panel.
WARNING:
Prior to disconnecting ignition switch, ground P-leads at magnetos to
prevent accidental firing of engine.
CAUTION: When removing wire leads from ignition switch, note EXACT location of
attaching leads for reference on reinstallation.
(e) Loosen screws from terminals on back of ignition switch and remove wire leads.
(2) Installation - Ignition Switch
(a) Connect wire leads to ignition switch. (Refer to 91-00)
(b) Perform ignition switch functional check. (Refer to 74-30)
(c) Position ignition switch in bolster panel, position placard on ignition switch, and install
retaining nut.
(d) Connect battery. (Refer to 24-30)
(e) Install engine cowling. (Refer to 71-10)
(3) Functional Check - Ignition Switch
(a) Acquire necessary tools, equipment, and supplies.
(b) Remove engine cowling. (Refer to 71-10)
(c) Disconnect battery. (Refer to 24-30)
(d) Check right P-lead continuity:
1
Remove P-lead from right magneto.
2
Attach P-lead to ohmmeter and to airframe ground.
3
With switch in OFF or L position, ohmmeter should indicate a closed circuit.
4
With ignition switch in R or BOTH position, ohmmeter should indicate an open cir-
cuit.
5
Connect P-lead to right magneto.
(e) Check left P-lead continuity:
Description P/N or Spec. Supplier Purpose
Ohmmeter -
Fluke
a
a. or equivalent
Test continuity
30 Nov 2000