Spark Plug Cleaning - Lycoming TEO-540-C1A Maintenance Manual

8. Spark Plug Cleaning

Refer to the spark plug manufacturer's cleaning instructions.
9. Spark Plug Gap Setting
A. Make sure the "Spark Plug Cleaning" procedure in Chapter 05-30 was completed and that the
inside of the spark plug barrel is clean and dry and does not have any residue from cleaning.
NOTICE: Serviceable spark plugs are to be re-installed, otherwise use new replacement long-
reach spark plugs per the TEO-540-C1A Illustrated Parts Catalog.
B. Before spark plug installation set the spark plug gap in accordance with the spark plug
manufacturer's instructions.
C. Reset and test the spark plugs in accordance with the spark plug manufacturer's instructions.
10. Spark Plug Rotation
NOTICE: As part of routine service, rotate spark plugs in different locations per Table 3 every 100
hours of engine operation or annually (whichever occurs first) or when there is evidence
of spark plug fouling.
A. Remove all of the spark plugs. Refer to the "Spark Plug Removal" procedure in this chapter.
B. Examine each spark plug and ignition lead. Refer to the "Spark Plug Inspection" and
"Ignition Lead Inspection" procedures in this chapter.
C. Complete the "Spark Plug Cleaning" procedure in Chapter 05-30.
CAUTION
D. Apply Copper-Based Anti-Seize (Figure 6) or engine oil to
the threads of each spark plug (starting two full threads from
the electrode.)
E. Rotate acceptable spark plugs - move the bottom spark plugs
to the upper position; move the upper spark plugs to the
bottom position, per the rotation scheme in Table 3.
F. Refer to the "Spark Plug Installation" procedure in this
chapter.
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USE CARE TO PREVENT THE COPPER-BASED ANTI-SEIZE FROM
GETTING ON THE SPARK PLUG ELECTRODE OR IN THE
COMBUSTION CHAMBER.
DO NOT APPLY A GRAPHITE-BASED COMPOUND TO THE SPARK
PLUG THREADS.
Spark Plug Rotation Scheme
#1 Top
#2 Top
#3 Top
#4 Top
#5 Top
#6 Top
TEO-540-C1A Engine Maintenance Manual
TEO-540-C1A Engine Maintenance Manual
Table 3
with #6 Bottom
with #5 Bottom
with #4 Bottom
with #3 Bottom
with #2 Bottom
with #1 Bottom
© 2018 Avco Corporation. All Rights Reserved
Figure 6
Copper-Based Anti-Seize
Applied to Spark Plug Threads
November 2018