Marathon — Exciter Installation
Repair & overhaul
From a Marathon service manual — check it applies to your exact model before use.
Before you start
- Belleville washers must be mounted in this direction.
Procedure
- Attach a wire to main rotor leads and feed through armature bore and out the lead hole.
- Align the key in the armature bore to the keyway in the shaft; slide armature on shaft.
- Insert the capscrew and belleville washer; torque to 84 ft-lb (1/2 in.) or 300 ft-lb (3/4 in.).
- Observe polarity markings and connect main rotor leads to rectifier; torque nuts to 4 ft-lb (5.4 N-m).
- Position exciter field leads at the left (9 o'clock) inboard position.
- Mount exciter stator on front end bracket mounting pads; torque capscrews to 60 ft-lb (81 N-m).
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 84 ft-lb (114 N-m) for 1/2 in. bolt
- 300 ft-lb (407 N-m) for 3/4 in. bolt
- Rectifier nuts 4 ft-lb (5.4 N-m)
- Exciter stator capscrews 60 ft-lb (81 N-m)
Source: Marathon service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.