Starting/Charging Systems (H4SO): Generator: Inspection: Brush

1. Measure the length of each brush. If wear exceeds the service limit, replace the brush. Each brush has the service limit mark (A) on it.

   Brush length: 

   Service limit (1) 

   5.0 mm (0.197 in) 

   Standard (2) 

   18.5 mm (0.728 in) 

   Fig 1: Measuring Length Of Brush

   Courtesy of SUBARU OF AMERICA, INC.
2. Checking brush spring for proper pressure

Using a spring pressure indicator, push the brush into the brush holder until its tip protrudes 2 mm (0.08 in). Then measure the pressure of brush spring. If the pressure is less than 2.648 N (270 g, 9.52 oz), replace the brush spring with a new one. The new spring must have a pressure of 4.609 to 5.786 N (470 to 590 g, 16.58 to 20.810 oz).

Fig 2: Checking Brush Spring For Proper Pressure

Courtesy of SUBARU OF AMERICA, INC.