SPRING 1W1788 - Caterpillar

Engine:
3306B (S/N: 8NS1-UP; LRW1-UP)
3406C (S/N: 9ES1-UP; LRX1-UP)
3406E (S/N: 8AZ1-UP)
3412 (S/N: 4BZ1-UP)
3412C (S/N: 9EP1-UP; BCW1-UP; LRY1-UP)
3456 (S/N: CCB1-UP; CBX1-UP)
Description of Change: Effective July 2003, the VR6 voltage regulator became the standard regulator in production. This voltage regulator has the droop rheostat installed on the face of the regulator. Therefore, an external rheostat assembly is not required.Adaptable To: The 202-8634 Voltage Regulator Gp (VR6) replaces the VR3 voltage regulator in production. The 202-8634 Voltage Regulator Gp is a direct replacement for VR3 voltage regulators that currently exist in the field. When upgrading from a VR3 voltage regulator (equipped with the 4P-3848 Current Transformer Gp ) to the 202-8634 Voltage Regulator Gp (VR6), refer to the procedure below. This procedure needs to be followed in order for the droop circuit to operate properly.Replacement Procedure
Disconnect and remove the 7C-8760 Rheostat Assembly from the VR3 regulator and the 9Y-9437 Transformer .
Label the wires that go to the connector on the 9Y-9437 Transformer .
Cut off the connector from the 9Y-9437 Transformer. When cutting off the connector, make the cut as close to the connector as possible.
Install fork terminals on the 9Y-9437 Transformer wires.
Disconnect the sensing leads from the VR3 voltage regulator.Note: The sensing leads connect to the same terminals on the VR3 and the 202-8634 Voltage Regulator Gp (VR6).
Remove the VR3.
Install the VR6 in place of the VR3.
Connect the sensing leads to the VR6.
Install the black wire from the 9Y-9437 Transformer to Terminal 5 or Terminal 5A on the 202-8634 Voltage Regulator Gp (VR6).
Connect a 1 ampere droop circuit between Terminal 5 and Terminal 6 on the VR6 voltage regulator.
Connect a 5 ampere droop circuit between Terminal 5A and Terminal 6 on the VR6 voltage regulator.
Install the white wire from the 9Y-9437 Transformer to Terminal 6 on the VR6 voltage regulator.For schematic and droop operation information, refer to Specifications, Systems Operation, Troubleshooting, Testing and Adjust, RENR2480, "VR6 Voltage Regulator".