Chapter 4 - Check; General; Inspection Checks - Planet ES-10024B-1 Maintenance Manual

Aircraft Alternator
Maintenance Manual
4.1

General

A. This section defines the various checks and inspections needed to assure reliable and safe
operation of the alternator while in service. They are listed in hours time in service (TIS) or in
calendar time, whichever is applicable and are the first to occur when offered a choice. Some
maintenance is one time initial and others are recurring.
B. HET recommended maintenance and checks including TIS may be superseded by the aircraft
or engine manufacturer's established time limits and schedules based on experience and/or
unique requirements under engine or airframe Type Certificate.
4.2

Inspection Checks

100 Hours TIS & each 100 hours thereafter. (or each annual/event, the first to occur)
Perform a check of the alternator assembly. Note through bolt security and proper safety wire
application. Re-torque if bolts are found loose. Check the alternator to engine mounting bolts for
proper torque per aircraft, rotorcraft and/or engine service instructions or maintenance manual.
Inspect area around the brush holder for soot. If a large amount of soot appears, remove each
brush and check for wear or damaged brushes. If severe wear has occurred, check slip rings for
gouges or scratches. Check all terminal hardware for tightness and insulators for condition.
500 Hours TIS & each 500 hours thereafter. (or each two years, the first to occur)
Remove each brush and check for wear or damaged brushes. If brush shows more than 50%
wear or has chips or damage, replace brushes (brushes must be replaced as a set only). New
brushes are 0.50 inch (12.7 mm) long. With the alternator removed, check the drive coupling
or visually check belt and belt drive line components. Adjust belt tension to proper values per
engine/aircraft service instructions or maintenance manual. Examine the alternator insulators and
replace if cracked or burnt. Inspect the aluminum housing for surface corrosion, clean and treat.
Inspect housings for cracks around through bolt holes and ears.
TBO Unlimited Hours TIS
Overhaul or replacement is based on the condition of the alternator.
based on cooling, electrical load and general service. When published, the aircraft OEM TBO
shall supersede this HET recommendation.
ES1031
Rev. A: 11 Aug. 2021

CHAPTER 4 - CHECK

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Overhaul time may vary
24-30-01
Page: 4-1