Bridgeport 12193443 Shifter Crank Assembly Milling Machine

Product Description

The BRIDGEPORT 12193443 is a shifter crank assembly designed as a direct replacement component for Bridgeport milling machines. This assembly is part of the J-Head top housing mechanism, where it provides the mechanical linkage needed to shift spindle speeds or engage gear ranges during machine operation. It is a service and maintenance part used by machine tool technicians and millwrights performing repairs on Bridgeport-style knee mills. The component is sold as an individual assembly, making it suitable for targeted repairs without requiring a full subassembly replacement.

This shifter crank assembly is intended for use with Bridgeport I Series milling machines equipped with the J-Head top housing. It fits into the gear-shifting mechanism located in the upper head casting. This part is typically needed when the existing crank is worn, damaged, or missing, causing difficulty engaging spindle speed ranges. It is a common service item in machine shops, vocational training facilities, and manufacturing environments where Bridgeport-style vertical knee mills are in regular service.

Key Features

• Direct-fit shifter crank assembly for J-Head top housing applications
• Compatible with Bridgeport I Series milling machines
• Sold as a complete assembly for straightforward component replacement
• OEM-style fitment supports accurate reinstallation without modification
• Individual unit packaging supports single-unit repair orders

Compatibility

Designed for use with Bridgeport I Series milling machines fitted with the J-Head top housing, as specified by the manufacturer.

Installation Notes

Installation of this shifter crank assembly should be performed by a qualified machine tool technician or millwright. Before beginning disassembly, power down the milling machine completely and lock out the main disconnect per OSHA lockout/tagout procedures. Access to the J-Head top housing typically requires removal of the top cover and related hardware. Refer to the Bridgeport J-Head service manual for the correct disassembly sequence and reassembly torque specifications before proceeding.