Boston Gear 34678 Sleeve Bearing 3/8 in Id Oil Bronze

Product Description

The BOSTON GEAR 34678 is an oil impregnated bronze sleeve bearing designed to support rotating shafts in a wide range of light-duty and medium-duty mechanical assemblies. With a 0.377-inch inside diameter, a 0.627-inch outside diameter, and a 0.5-inch overall length, this plain bore bearing provides a self-lubricating interface between shaft and housing. The sintered bronze construction retains oil within its porous matrix, releasing it continuously during operation to reduce friction and extend service life without the need for frequent external lubrication. It is rated for a maximum pressure-velocity (PV) value of 50,000 psi, and it conforms to SAE 20 (ISO 68) and SAE 30 (ISO 100) oil standards. Maintenance technicians, millwrights, and HVAC or pump repair specialists are the typical installers.

This bearing is suited for residential and light commercial applications where low-speed, moderate-load shaft support is required. Common install scenarios include electric motor rebuilds, fan assemblies, small pump shafts, conveyor components, and appliance drive mechanisms. The compact 0.5-inch length makes it a practical choice for space-constrained housings where a standard sleeve bearing is called for. Its oil impregnated bronze material performs reliably in environments where re-lubrication access is limited or impractical.

Key Features

• Oil impregnated bronze construction delivers continuous self-lubrication without external grease fittings
• Plain bore design accepts standard 3/8-inch shafts with a nominal inside diameter of 0.377 inches
• Maximum PV rating of 50,000 psi supports moderate-load, low-to-medium speed applications
• Conforms to SAE 20 (ISO 68) and SAE 30 (ISO 100) lubricant standards
• Compact 0.5-inch overall length suits tight axial clearance installations
• Weighs approximately 0.023 pounds, minimizing added mass in precision assemblies

Compatibility

Designed as an OEM-style replacement sleeve bearing for mechanical assemblies requiring a plain bore, oil impregnated bronze bushing with a 3/8-inch inside diameter and 5/8-inch outside diameter.

Installation Notes

Sleeve bearings of this type are installed by pressing the bearing into a prepared housing bore to achieve proper interference fit; a bearing press or arbor press is recommended to avoid cocking the bearing during installation. Ensure the housing and shaft surfaces are clean and free of burrs before pressing. Power down and de-energize all equipment before beginning bearing replacement. Do not hammer directly on the bearing face, as this can distort the bore and compromise oil retention in the sintered matrix.