Lycoming TEO-540-C1A Maintenance Manual page 115

TEO-540-C1A Engine Maintenance Manual
TEO-540-C1A Engine Maintenance Manual
Problem
Rough Idle
Engine will not idle
unless the boost pump
is on
© 2018 Avco Corporation. All Rights Reserved
November 2018
Table 1 (Cont.)
Fault Isolation Guide
Cause
Fault in the ignition
system
Uneven cylinder
compression
Engine to airframe
ground strap not
connected or broken
Battery negative cable
loose or faulty connection
to airframe
Discharged battery or
weak charging system
Low fuel pressure
Corrective Action
1. Visually examine the
harness for physical damage.
2. Examine leads using a high-
tension lead tester.
3. Replace worn or damaged
components as necessary.
4. Complete the following
procedures:
• Spark Plug Removal
• Ignition Lead Inspection
• Spark Plug Inspection
• Spark Plug Cleaning
• Spark Plug Gap Setting
• Spark Plug Rotation
• Spark Plug Installation
1. Complete the cylinder
compression check.
2. Complete a borescope
inspection of low-pressure
cylinder(s).
Clean terminals. Reconnect
ground strap and preform a
continuity check.
Ensure battery cables are
properly connected and tight.
Preform a continuity check.
Replace with a charged battery.
Test charging system
1. Complete a check for a
blocked fuel pump filter and
an inoperative NTO light.
2. Replace the fuel pump or
fuel pressure regulator.
Ref.
74-20
&
05-30
72-30
AMM
AMM
AMM
73-10
12-30
Page 85