LOCKNUT 6V7688 - Caterpillar

Engine:
3508B (S/N: S2B1-UP)
3508C (S/N: TTB1-UP)
3512 (S/N: 65Z1-UP)
3512B (S/N: PTF1-UP; S2J1-UP; S2L1-UP; PTM1-UP; 1GZ1-UP)
3512C (S/N: TTC1-UP; TTF1-UP; SLM1-UP; E3W1-UP; E3Y1-UP)
3516B (S/N: S2P1-UP; S2R1-UP; S2S1-UP; S2X1-UP)
3516C (S/N: TTD1-UP; PAG1-UP; TTH1-UP; TTJ1-UP; JTS1-UP)
Petroleum Engine:
3512C (S/N: LLB1-UP)
3516C (S/N: PES1-UP)
Engine News, SEBD9921, 20 December 2013, "New Jacket Water Heater Groups Are Used on Certain 3500 Engines". The original article has been revised to update the effective serial numbers.Description of Change: The new jacket water heater groups are more resistant to vibration and are no longer dual voltage.Adaptable To: The new jacket water heater groups replace the former jacket water heater groups.The new jacket water heater groups are adaptable to the above listed engines back to first production.The new jacket water heater groups and former jacket water heater groups are listed in Tables 12.
Table 1
Single Voltage Heater    
Former Part    Voltage    New Part    
7E-6248 Jacket Water Heater Gp     240V     430-2751 Jacket Water Heater Gp    
Table 2
Dual Voltage Heater    
Former Part    Voltage    New Part    
7E-6247 Jacket Water Heater Gp     120V     430-2750 Jacket Water Heater Gp    
240V 430-2751 Jacket Water Heater Gp    
200-6504 Jacket Water Heater Gp     240V     430-2751 Jacket Water Heater Gp    
480V 430-2752 Jacket Water Heater Gp    The effective serial numbers are listed in Table 1.
Table 3
Effective Serial Numbers    
S/N:S2B00841-UP    
S/N:TTB00575-UP    
S/N:65Z01628-UP    
S/N:1GZ00245-UP    
S/N:PTF92005-UP    
S/N:PTM03002-UP    
S/N:S2J00793-UP    
S/N:S2L00988-UP    
S/N:E3W00367-UP    
S/N:E3Y00393-UP    
S/N:LLB00154-UP    
S/N:SLM00539-UP    
S/N:TTC00625-UP    
S/N:TTF00586-UP    
S/N:PAG00483-UP    
S/N:S2P00253-UP    
S/N:S2R00805-UP    
S/N:S2S00495-UP    
S/N:S2X01699-UP    
S/N:JTS00459-UP    
S/N:PES00961-UP    
S/N:TTD00418-UP    
S/N:TTH00841-UP    
S/N:TTJ00524-UP