Spark Plugs - Lycoming TEO-540-C1A Maintenance Manual

TEO-540-C1A Engine Maintenance Manual
TEO-540-C1A Engine Maintenance Manual

2. Spark Plugs

Two long reach spark plugs (Figure 5) are installed on each cylinder head (Figure 2) of the
engine for a total of 12 spark plugs per engine.
NOTICE: Typically, engines with long reach spark plugs are identified by yellow paint on the
cylinder fins between the spark plug hole and the rocker covers where shown in
Figure 5.
Refer to the TEO-540-C1A Illustrated Parts Catalog to identify the correct spark plug approved
for use in these engines.
3. Spark Plug Removal
A. Make sure that the battery is disconnected from the engine.
B. Hold the ferrule and loosen the spark plug nut and disconnect it from the ignition lead.
CAUTION
C. Use the applicable sized socket on top of the spark plug and turn the socket to remove the
spark plug from the engine cylinder head (Figure 2).
D. Identify by tag or label each spark plug as it is removed, according to cylinder number and
top or bottom position.
E. Remove and discard the gasket from the spark plug.
4. Ignition Lead Inspection
NOTICE: The ignition leads are an all-weather, shielded wire constructed with over-braid.
A. Examine spark plug ignition leads (Figures 1 and 2) and spark plug ceramics for corrosion
and deposits.
B. Examine each ignition lead for chafing, insulation breakdown, frayed wiring, deterioration,
heat damage, wear, and cracking. Replace the harness if any lead shows chafing, cracks, or
wear, frayed wiring, or damage.
C. Examine the ignition lead connections. Make sure the ignition lead connections (Table 1) are
secure.
D. Make sure the ignition lead mounting clamps are tight.
© 2018 Avco Corporation. All Rights Reserved
November 2018
Long Reach Spark Plug & Location
HOLD FERRULES WHILE LOOSENING THE SPARK PLUG COUPLING
NUT TO PREVENT TWISTING THE CONDUIT OR CABLE.
Figure 5
74-20
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