Heald Bore-Matic Service Manual

Service manual for Heald Bore-Matic boring machines, covering models 221, 222, 224, 321, 322, 324, 421, 422, 424, 425, and 426. This workshop manual provides complete technical guidance for maintenance, troubleshooting, and repair across single and multi-spindle configurations. The manual begins with general machine description and installation procedures, then moves into detailed operating instructions for all control mechanisms—push buttons, hand throttle, feed cams, and tappet adjustment. You'll find comprehensive coverage of pilot valve operation, throttle systems, and boring head control essential for both routine setup and problem diagnosis. The hydraulic system section documents the power unit, check valves, relief valves, and oil pressure settings across all operating modes, with fully illustrated circuits for rapid advance, fast feed, advance start, slow feed, table stop, two-way boring, intermediate stop valve function, start valve operation, and correction of uneven table motion. Parts list information supports field repair and component replacement. This PDF serves as the authoritative reference for keeping Bore-Matic machines running reliably in production.