Mazda CX-9 Grand Touring 2009 Manual page 563

1. Inspect brushes for wear.
If any brush is worn almost to or beyond the limit, replace all of the brushes.
Generator brush length
Standard: 22.5 mm {0.89 in}
Minimum: 5.0 mm {0.20 in}
Fig. 13: Identifying Brush Length
Courtesy of MAZDA MOTORS CORP.
Brush spring
1. Measure the force of the brush spring using a spring pressure gauge.
2. Read the spring pressure gauge at the brush tip projection of 2 mm {0.079 in} .
Replace the brush spring if necessary.
Generator brush spring force
Standard: 4.1-5.3 N {0.42-0.54 kgf, 0.92-1.19 lbf}
Minimum: 1.7 N {0.17 kgf, 0.38 lbf}
Fig. 14: Measuring Force Of Brush Spring With Spring Pressure Gauge
2008 Mazda CX-9 Grand Touring
2008 ENGINE Charging System (MZI-3.7) - Mazda CX-9