BASE-VALVE MECHANISM COVER 2226953 - Caterpillar

Illustration 1 g00901139
27-SI End View
Table 1
27-SI Alternators    
Part Number     Nominal Voltage     Nominal Current    
9L-5938 Alternator Gp     12 V     58 A    
3T-7070 Alternator Gp     12 V     58 A    
9W-1082 Alternator Gp     12V     83 A    
Table 2
Specifications for 27-SI Alternators (1)    
CAT Part Number    9L5938    3T7070    9W1082    
Torque of Pulley Nut (4)     100 7 N m (75 5 lb ft)    
100 7 N m (75 5 lb ft)    
100 7 N m (75 5 lb ft)    
Torque of Four Through Bolts (3)    
6.2 0.6 N m (5.5 5 lb in)    
6.2 0.6 N m (5.5 5 lb in)    
6.2 0.6 N m (5.5 5 lb in)    
Torque of "B+" Terminal (Nut) (1)    
7.1 0.9 N m (63 8.0 lb in)    
7.1 0.9 N m (63 8.0 lb in)    
7.1 0.9 N m (63 8.0 lb in)    
Torque of "B-" Terminal (Bolt) (2)    
2.3 0.6 N m (20 5 lb in)    
2.3 0.6 N m (20 5 lb in)    
2.3 0.6 N m (20 5 lb in)    
Voltage Rating     12 V     12 V     12 V    
Rated Output Current     58 A     58 A     83 A    
Polarity     Negative Ground     Negative Ground     Negative Ground    
Rotation     CW or CCW     CW or CCW     CW    
Test Speed     5000 rpm     5000 rpm     7000 rpm    
Rated Output Current at the Test Speed     37.0 A     47.8 A     61.1 A    
Output Voltage at
25 °C (77 °F)     27.4 0.6 V     27.4 0.6 V     14.0 0.3 V    
Resistance of Rotor Field Winding at
27 °C (81 °F)     2.4 to 2.7 ê     2.4 to 2.7 ê     2.2 to 2.7 ê    
Current of Rotor Field Winding at the Voltage Rating and
27 °C (81 °F)     3.3 to 3.8 A     2.5 to 2.8 A     5.7 to 7.1 A    
Turn-On Speed at
25 °C (77 °F)     2000 rpm     2000 rpm     2000 rpm    
( 1 ) Refer to Illustration 1.