Marathon — Field Flashing
Maintenance · Automatic voltage regulator / exciter field
From a Marathon service manual — check it applies to your exact model before use.
Before you start
- Failure to remove the exciter field leads from the automatic voltage regulator during flashing procedures may destroy the regulator.
- Batteries may explode when exposed to an electric arc.
Procedure
- Remove the exciter field leads from the automatic voltage regulator during flashing procedures.
- Connect the F+ and F- leads to the battery's corresponding positive and negative terminals.
- Use an appropriate length of lead wire to separate the battery from the point of connection.
- After 3 to 5 seconds, remove the F- lead; an inductive arc should result.
- If no arc is drawn, repeat the procedure.
- Reconnect the F+ and F- leads to the regulator.
- Restart the generator and verify that terminal voltage is developed.
- If terminal voltage does not develop, repeat the field flashing procedure and/or consult the troubleshooting section.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- 3 to 5 seconds
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.