The Pentair Mechanical Shaft Seal Set (354545S) is the OEM replacement 5/8 in. mechanical seal for the SuperFlo, SuperFlo VS/VST, SuperMax, SuperMax VS, Challenger, OptiFlo, and Dynamo pump families. IMPORTANT: THIS LISTING IS FOR A SEAL SET (KIT)Part 354545S is sold as a seal set — both the rotating and stationary seal faces are included. You are purchasing a complete replacement kit, not an individual seal component. IMPORTANT: MANUFACTURE DATE RESTRICTION — SUPERFLO VS/VST AND SUPERMAX VS PUMPSThis seal set fits SuperFlo VS/VST and SuperMax VS variable speed pumps manufactured before June 17, 2019. Pumps built on or after that date use a different seal specification. Check the date code on your pump's nameplate before ordering. The mechanical shaft seal sits between the pump's wet end and motor, preventing water from migrating along the shaft into the motor housing. When the seal wears or fails, water can reach the motor bearings, causing premature motor failure. Replacing the shaft seal at the first sign of leakage behind the pump volute protects the motor and restores dry-running integrity. Specifications Pentair Part Number 354545S Part Name Mechanical Shaft Seal, 5/8 in. Shaft Diameter 5/8 in. Quantity Included Set (Kit) Sub-Category Pump Parts — Seals Fits Into Brand Equipment Line Model / Part Number Notes Pentair SuperMax 348191 Seal Set Pentair OptiFlo OPTIFLO — Pentair Challenger CHALLENGER-HIGH-FLOW Challenger High Flow Pump standard mechanical seal Pentair SuperFlo SUPERFLO-VS-VST Mfg. Before 06/17/19 Pentair SuperMax SUPERMAX-VS Mfg. Before 06/17/19 Pentair Challenger CHALLENGER Mechanical seal, 5/8 in. PS 200 Pentair Dynamo DYNAMO — Pentair Challenger CHALLENGER HIGH PRESSURE PUMP 5/8 in. mechanical seal PS 200 Pentair SuperFlo SUPERFLO VS/VST Shaft Seal — Mfg. Before 06/17/19 Pentair SuperMax SUPERMAX VS Shaft Seal — Mfg. Before 06/17/19 Pentair SuperFlo 354803S SuperFlo Pump seal set — 3/4 HP Single Speed Motor Pentair SuperFlo 354821S SuperFlo Pump seal set — 1 HP Single Speed Motor Pentair SuperFlo 354823S SuperFlo Pump seal set — 1-1/2 HP Single Speed Motor Pentair SuperFlo 354815S SuperFlo Pump seal set — 2 HP Single Speed Motor Pentair SuperMax 354804S Seal Set — SuperMax Pump, 3/4 HP Motor. Verify fitment before ordering. Pentair SuperMax 354822S Seal Set — SuperMax Pump, 1 HP Motor. Verify fitment before ordering. Pentair SuperMax 354824S Seal Set — SuperMax Pump, 1-1/2 HP Motor. Verify fitment before ordering. Pentair SuperMax 354816S Seal Set — SuperMax Pump, 2 HP Motor. Verify fitment before ordering. Pentair SuperMax 355021S Seal Set — SuperMax Pump, 1 HP SQFL Motor. Verify fitment before ordering. Pentair SuperMax 355023S Seal Set — SuperMax Pump, 1-1/2 HP SQFL Motor. Verify fitment before ordering. ...and additional compatible models. Verify your model number with your equipment manual before ordering. Compatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering. Poolaroo Pro Tip A weeping seal is always easier and cheaper to fix than a failed motor. If you see a small drip from the area directly behind the pump volute — particularly after the pump shuts off — that's the mechanical seal telling you it's time. When replacing 354545S, clean the seal cavity thoroughly before seating the new faces, and never touch the polished seal faces with bare fingers. Handle both the rotating and stationary faces only by their rubber components to avoid contaminating the mating surfaces, which shortens seal life significantly.
