Usage:
325B L (2JR),
330B L (6DR) Excavators
Description of Change: Washers are now added between the return spring and the retainer of the Boom I valve in the main hydraulic control valve. Adding the washers reduces the initial rapid boom movement and improves boom modulation when the pilot hand control valve is actuated.
Adaptable To: The addition of two 5D-1247 Washers to the Boom I valve is effective with 325B L (2JR585, 588, 591-596, 598-Up) Excavator and 330B L (6DR468, 476, 483, 486-504, 506-Up) Excavator. The use of the washers is adaptable to 325B L (2JR1-Up) and 330B L (6DR1-Up) Excavators.
Illustration 1. View of typical main control valve to identify Boom I valve (B).
Illustration 2. Section view of Boom I valve and location of 5D-1247 Washers (4). (1) Spring. (2) Retainer. (3) Bolt.