1. Alternator brushes can only cause problems if they are worn out. The brushes are part of the exciter circuit of the e / m field and are supported by rings on the rotor.
2. Disconnect the wires from the battery. Remove the 2 nuts on the end of the alternator (next to the wire "8", labeled "EXC") and carefully pull out the brush holder (see photo).
3. Inspect the brushes for abrasion and check their length and fit in the brush holder. Install new brushes as needed. In the absence of new brushes, take the generator to a workshop to replace the brushes. If the brushes get stuck in the brush holder, you can lightly file them with a fine file (at the same time, make sure that the landing of the brushes does not become too loose). Clean the brushes of dirt with a lint-free cloth soaked in gasoline and wipe the slip rings clean.
4. Installation of brushes is made in the reverse order. Be careful not to damage the brushes when reinstalling them. Connect the wires to the generator and then to the battery, after which you can start the engine.