AMT 1640-162-98 Mechanical Seal - Viton Type 21

The AMT 1640-162-98 is a Mechanical Seal, Viton, Type 21, size 3/4 Inch for an AMT Stainless Steel Centrifugal Pump. MECHANICAL SEAL REPLACEMENT
REMOVAL OF OLD SHAFT SEAL 1. Disconnect power supply and piping. 2. Place unit in vertical position with pump end up. 3. Disassemble pump by removing fasteners and washers which holds casing in place. Lift off casing and casing seal . 4. Unscrew impeller nut , and impeller separately by turning each counterclockwise. Impeller seal will also be freed at this time. If seal head is retained on impeller, separate at this time. NOTE: It may be necessary to use a soft hammer to tap outside of impeller in a counterclockwise direction to loosen it. NOTE: Access to motor shaft is provided at end opposite pump . Use screwdriver in slot or wrench on flats to keep motor shaft from turning. 5. Lift off casing cover while pulling seal along with it. Seal seat can now be freed by pressing through from rear of casing cover. IMPORTANT: Do not damage motor shaft, impeller stem or seal cavity in casing cover as this may cause leaks. INSTALLATION OF NEW SEAL The precision lapped faces of mechanical seal are easily damaged. To prevent leaks, handle replacement seal carefully. Do not touch seal mating faces. 1. Clean seal cavity area of casing cover . Lubricate rubber portion of seal seat with soapy water. Protect seal face with cardboard and press squarely into place, with polished side up. Then lay casing cover onto adapter , and center it around motor shaft. IMPORTANT: To avoid rubbing during operation, maintain gap between seal and motor shaft until assembly is complete. 2. Clean outside of shaft stem on impeller . Lubricate inside rubber portion of seal head with soapy water. Gently slide seal onto impeller with polished side facing away from impeller. 3. Clean outside of shaft. Lubricate inside rubber portion of seal head with soapy water. Gently slide seal onto impeller with polished side facing towards motor. Be careful not to damage seal face. NOTE: Impeller is designed to use no spring retainer between impeller and spring. If replacement seal is equipped with spring retainer, discard retainer. 4. Carefully screw impeller back onto motor shaft by turning clockwise. Be sure to snug-up impeller by holding motor shaft as during disassembly. Add impeller nut , then impeller nut and tighten. 5. Carefully lay casing seal into desired position. NOTE: Casing may be rotated to position discharge port at various angles. 6. Use fasteners and washers to attach casing. IMPORTANT: To avoid leaks, be sure to tighten fasteners in stages to prevent casing seal from slipping and becoming pinched. 7. When assembly is complete, check for interference by spinning motor shaft by hand and listening. If rubbing heard, loosen fasteners and adjust casing cover until rubbing is gone . If rubbing still persists, remove casing. Then check to be sure impeller is completely tightened and not binding on shaft threads. Seal will produce minor drag when spinning motor shaft, but rubbing anywhere else must be eliminated! Otherwise, damage to pump and/or motor may occur.