ENSTROM F-28F/280F SERIES MAINTENANCE MANUAL
Rev.
6
MM-6-5
Apr
7/15
6-3. Alternator
A.
General
Information
The aircraft alternator is a belt driven type. The alternator output rating is 70 amperes
continuous at approximately 12 volts D.C. or 28 volts D.C., depending on the
electrical system. Principle components of the alternator are the stator, the rotor, the
slip ring end head, the drive end head and the rectifier diodes.
B.
Troubleshooting
The following list suggests areas to be investigated should alternator performance be
suspect:
(1) Brushes – Remove and inspect for condition and seating
(2) Rotor – Test for ground or shorted windings
(3) Rectifier Diodes – Test for open or shorted diodes
(4) Stator – Test for open
(5) Bearings – Check for roughness or excessive clearance.
(6) Housing cleanliness – End housing should be kept clean by wiping with a cloth
dampened in solvent
NOTE: It is recommended that the service manual applicable to your alternator type
be consulted for detailed repair procedures.
C.
Alternator
– Removal (see Figure 6-1)
(1) Disconnect battery cables.
(2) Remove cowling and baggage box.
(3) Remove jackstrut and pulley assembly. (See Section 11-4 for Jackstrut Removal
Procedure).
(4) Remove the fan assembly exposing the alternator.
(5) Remove the four bolts attaching auxiliary oil cooler and lower the cooler.
NOTE: Allow oil cooler to hang free on attached oil lines.
(6) Remove the lower access panel from fan shroud located above the auxiliary oil
cooler.
(7) Cut safety wire on bolt securing alternator belt tension arm and remove bolt.
Pivot alternator and remove v-belt from alternator pulley.
(8) Disconnect wires from alternator.
NOTE:
Identify
wires
for
re-installation.
(9) Remove the two alternator mount bolts and remove alternator.
UNCONTROLLED COPY WHEN DOWNLOADED OR PRINTED
Visit www.enstromhelicopter.com for instructions to order an original manual and to register for email notification of updates.