Browning 1028273 Single Groove Sheave 4.25 in Od Cast Iron

Product Description

The BROWNING 1028273 is a finished bore single groove sheave designed for use with classical V-belts in belt-drive power transmission systems. This cast iron sheave features a 4.25-inch outside diameter and a pre-finished 0.75-inch bore, eliminating the need for additional machining before installation. The belt groove is sized for 4L or A-section belts with a pitch diameter of 3.5 inches and a B-section pitch diameter of 3.9 inches. At 2 pounds, it is compact and well-suited for light-to-medium duty drive applications. HVAC technicians, millwrights, and mechanical contractors commonly install this type of sheave on blower assemblies, fan drives, and auxiliary equipment drives.

This sheave is used in residential and light commercial belt-drive applications where a single-groove A or 4L section V-belt connects a motor to a blower, fan, or pump. The finished bore accepts a 0.75-inch shaft directly, making it a straightforward drop-in component for standard motor shaft sizes commonly found in air handling units, exhaust fans, and belt-driven equipment. The overall length through the bore is approximately 1-5/32 inches, which should be confirmed against available shaft engagement before installation.

Key Features

• Finished 0.75-inch bore — no additional machining required for standard shaft fitment
• Compatible with 4L and A-section V-belts at a 3.5-inch pitch diameter
• B-section belt pitch diameter of 3.9 inches for cross-reference applications
• Cast iron construction provides durability in continuous-duty drive applications
• Single groove design suited for single belt power transmission setups
• Overall bore length of 1-5/32 inches supports positive shaft engagement

Compatibility

Designed as an OEM-style replacement or upgrade sheave for belt-drive systems using 4L or A-section single-groove V-belts with a 0.75-inch shaft diameter.

Installation Notes

Installation should be performed by a qualified HVAC technician or mechanical contractor. Disconnect and lock out all power to the drive system before removing or installing any sheave. Ensure the shaft is clean and free of burrs before sliding the sheave into position, and verify proper belt tension and sheave alignment using a straightedge or laser alignment tool after mounting. Refer to the equipment manufacturer's service documentation for drive system specifications.