RING-THRUST 3529703 - Caterpillar

Electric Power Generation:
SR4 (S/N: 1MS1-UP; 2ED1-UP; 3RD1-UP; 4SJ1-UP; 5DA1-UP; 5NJ1-UP; 5TD1-UP; 5UA1-UP; 6CA1-UP; 6EJ1-UP; 6FA1-UP; 6LA1-UP; 6MA1-UP; 6NA1-UP; 6NW1-UP; 6PA1-UP; 6SA1-UP; 6TW1-UP; 6ZW1-UP; 7AJ1-UP; 8FD1-UP; 8HG1-UP; 8SW1-UP; 8WW1-UP; 9DW1-UP; 9FG1-UP; 9HW1-UP; 9LW1-UP; 9RW1-UP; CFY1-UP; CXH1-UP; CXJ1-UP)
SR4B (S/N: 4RJ1-UP; AER1-UP; AFE1-UP; AFH1-UP; AFK1-UP; AFN1-UP; AFR1-UP; AGE1-UP; CXF1-UP)
Engine:
3406C (S/N: KPS1-UP; 2AM1-UP; 4BM1-UP)
3408 (S/N: 78Z1-1143)
3408B (S/N: 78Z1144-UP)
3408C (S/N: TAM1-UP; 1TS1-UP)
3412 (S/N: 81Z1-14500)
3412C (S/N: 5FL1-UP; 81Z14501-UP; 9BR1-UP; 9EP1-UP)
3412E (S/N: TGC1-UP)
3456 (S/N: 9BZ1-UP)
3508 (S/N: 8TL1-UP)
3512B (S/N: 4DR1-UP)
3516 (S/N: PTD1-UP)
G3408 (S/N: 6RJ1-UP)
G3408C (S/N: BAZ1-UP)
G3412 (S/N: R7A1-UP; KAP1-UP)
Description of Change: A new star-type lockwasher is now being used in the termination of the wiring conductor terminals for generator varistors. This new star-type lockwasher will help provide a more secure connection at the generator varistor conductor terminals and thus improve varistor reliability.Adaptable To: The 1H-4393 Lockwasher is now used in the termination of the wiring conductor terminals for 9Y-9412 Varistors. The 1H-4393 Lockwasher is effective with the serial numbers listed in Table 1 and is adaptable to the serial numbers listed above.In the event of field service work requiring the replacement of the generator varistor, a new 1H-4393 Lockwasher should be used when installing the new varistor. A new 1H-4393 Lockwasher should also be used if the varistor wiring conductor terminals become loose and require tightening. The 1H-4393 Lockwasher should not be recycled during field service work. It is recommended that you use a new 1H-4393 Lockwasher whenever you are required to replace the generator varistor.
Table 1
Effective Serial Numbers for the 1H-4393 Lockwasher    
Sales Model     Effective Serial Number    
SR4     S/N:5NJ01107    
S/N:8SW00684
S/N:9RW01562
S/N:CFY02412
SR4B     S/N:AER00420    
S/N:AFE00569
S/N:AFH00338
S/N:AFK00632
S/N:AFN00886
S/N:AFR00587
S/N:AGE01015