Piper PA-28-161, Maintenance Manual

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PIPER AIRCRAFT, INC.
PA-28-161, WARRIOR III
MAINTENANCE MANUAL
PAGE 1
Nov 30/06 5C7
74-10-00
ELECTRICAL POWER SUPPLY
1. Ignition System
WARNING: FAILURE TO CONSULT APPLICABLE VENDOR PUBLICATION(S), WHEN SERVICING
OR INSPECTING VENDOR EQUIPMENT INSTALLED IN PIPER AIRCRAFT, MAY
RENDER THE AIRCRAFT UNAIRWORTHY. (SEE INTRODUCTION - SUPPLEMENTARY
PUBLICATIONS.)
A. Description
Ignition of the fuel charge in each cylinder is accomplished by two spark plugs independently
excited by one of two Slick 4300 series magnetos. Each magneto separately generates, times and
distributes high tension (voltage) through leads to each cylinder.
The magnetos are controlled by two switches in the overhead switch panel. With its switch OFF, the
magneto is grounded and will not produce spark. The right magneto fires all the lower spark plugs.
The left magneto fires all the upper spark plugs.
The right magneto is standard and the left magneto is an impulse-coupled type installed to retard
magneto ignition timing (see lag angle on magneto dataplate) and provide spark for engine starting.
As the engine is cranked, a spring in the impulse coupling is wound. When the engine crankshaft
reaches the proper position for starting, the spring in the impulse coupling is released to spin the
rotating magnet and produce the spark required to fire the engine. After the engine starts, the
impulse coupling flyweights disengage the coupling due to centrifugal action. The coupling then acts
as a straight drive and the magneto fires at the normal firing position of the engine.
NOTE: Check the magneto data plate to verify the specific model number and series of the
magneto being worked on.
B. Troubleshooting
See Chart 1.
C. Replacement Magnetos
An alternative to overhaul is complete magneto replacement with a new Slick magneto. New Slick
magnetos incorporate all the latest design features and may be a cost effective alternative to
overhaul.
D. Overhaul
Overhaul is required as conditions indicate, but in no case may Slick 4300 series magnetos time-in-
service exceed the TBO for the engine. Magnetos must also be overhauled after a lightning strike or
following a sudden engine stoppage.
Information provided in this section is intended to support magneto removal, cleaning, inspection,
replacement and timing. For magneto overhaul procedures, see Slick’s F-1100 Master Service
Manual available from:
Slick Aircraft Products
(See Introduction - Supplementary Publications)