Inspection And Testing - Yanmar 6LPA-STP2 Service Manual

Alternator Service
12/05

Inspection and Testing

Rotor Circuit and Slip Rings
1. Using an ohmmeter (Figure 11-19, (1)) check
the rotor circuit resistance. The rotor circuit
should have continuity between the slip rings. If
the resistance is not within specifications or
there is no continuity replace the rotor.
Rotor resistance:
• Standard resistance at 20°C (68°F) is 2.9 ohms
Figure 11-19
Figure 11-19
2. Using an ohmmeter (Figure 11-20, (1)) check
the rotor circuit for grounds. The rotor circuit
between the slip rings and rotor should have no
electrical continuity. If continuity is measured,
replace the rotor.
6LPA Service Manual
Figure 11-20
(1)
3. Inspect the slip rings for damage or scratches
on the surface. If the surface is damaged or
scratched, replace the rotor.
4. Measure the slip ring diameter using calipers
(Figure 11-21). If the slip ring diameter is not
within specifications, replace the rotor
Slip ring diameter:
• Standard Diameter - 14.2 to 14.4 mm (0.559 to
0.566 in.)
0004844
• Minimum Diameter - 12.8 mm (0.503 in.)
Figure 11-21
© 2007 Yanmar Marine International
ALTERNATOR
Figure 11-20
Figure 11-21
(1)
0004845
0004846
11-13