Note: Before replacing the generator brush, please prepare the necessary spare parts.
1. Open the hood and disconnect the wiring from the battery (start with the negative).
2. On E-series and F7P engines (with 16 valves), remove the generator as described in Chapter 5.
3. On C-series and F3P engines, the brush holder/regulator can be removed without removing the alternator.
4. If the generator cannot be removed, disconnect the electrical wiring from it (see illustrations).
6.4a. Disconnect the generator wiring - engine F3P.
6.4b. Remove the rubber boot...
6.4 sec....then disconnect the main power cable from the generator - F3P engine
5. Note the location of the brush holder/regulator wire on the B+ terminal of the generator. Unscrew the nut and disconnect the wire (see illustration).
6.5 Disconnect the regulator/brush holder wiring from the rear of the alternator - F3P engine.
6. Remove the plastic cover from the studs on the back of the generator (see illustration).
6.6 Remove the plastic cover from the back of the generator - F3P engine.
7. Remove the two screws securing the regulator/brush holder to the rear of the generator (see illustration).
6.7. Unscrew the mounting screws - F3P engine.
8. Disconnect the remaining wire from the terminal on the back of the generator, then remove the regulator/brush holder (see illustration).
6.8 Remove the regulator/brush holder - F3P motor.
9. Measure the length of the protruding part of the brush (see illustration).
6.9. Measure the length of the protruding part of the generator brush.
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The manufacturer doesn't specify any minimum values, but as a guideline, it shouldn't be less than 5 mm. If any brush is worn more than this, the regulator/brush holder should be replaced. If the brushes are still serviceable, clean them with a cloth dampened with fuel. Make sure the spring tension for both brushes is the same. The brushes should move freely in the holders.
10. Clean the generator rings with a cloth dampened with gasoline. Check the generator ring surfaces for scratches, burns or corrosion.
11. Install the regulator/brush holder in the reverse order of removal.
12. If the generator has been removed, install it as described in Chapter 5.