The Wacker Neuson 5200021703 is a genuine OEM Mechanical Seal designed for APT4S and APT4T series pumps. As a direct OEM replacement sourced from Wacker Neuson, this seal is manufactured to the same specification as the original component installed at the factory. It fits the APT4S Pump with Skid, APT4S Pump with Skid Cold Weather, APT4T Pump with Surge Brake, APT4T Pump with Electric Brake, and their respective Cold Weather variants. Verify your model and machine number against the fitment list before ordering to ensure a correct, confident match.
Key Features
- OEM-Grade Sealing Material — Manufactured to the same material and dimensional specification as the original seal, ensuring consistent compression and leak-free performance at the pump shaft interface.
- Drop-In Shaft Replacement — Designed to seat directly onto the pump shaft in the same position as the outgoing seal, with no alterations needed to surrounding pump components.
- Broad APT Series Coverage — Fits multiple APT4S and APT4T configurations including Surge Brake, Electric Brake, and Cold Weather variants, making it a single-part solution across the APT4 pump family.
- Leak Prevention at the Source — A worn or degraded mechanical seal allows fluid to migrate past the shaft, leading to pump inefficiency and potential damage to the motor or bearing assembly. Replacing it promptly restores the sealed boundary between the fluid end and the drive end.
- Fluid Containment and Operator Safety — A compromised mechanical seal can result in uncontrolled fluid leakage at the pump housing. Maintaining a properly functioning seal is essential to safe pump operation and site cleanliness.
The mechanical seal in a centrifugal pump creates a dynamic barrier between the rotating pump shaft and the pump housing, preventing the fluid being pumped from escaping along the shaft. It works by holding two precision-lapped faces — one stationary and one rotating — in contact under spring load, forming a nearly frictionless yet fluid-tight interface. When this seal wears, cracks, or loses its face-to-face contact, fluid begins to leak outward at the shaft, which can accelerate bearing wear and ultimately cause pump failure if left unaddressed.
Part Details
| Part Number | 5200021703 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Mechanical Seal |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT4S Pump w/Skid, Cold Weather | APT4S CW | 5200019798 |
| APT4S Pump w/Skid | APT4S | 5200018977 |
| APT4T Pump, Surge Brake, Cold Weather | APT4T CW | 5200019792, 5200019793 |
| APT4T Pump, Surge Brake | APT4T | 5200019643, 5200019644 |
Verify Before You Order
Fitment is machine-number and revision-specific; always confirm your model and serial number against the fitment list.
Why Buy From DHS Equipment
Every part is verified against the manufacturer's part number before it ships, so what you order is what arrives. We carry parts from leading OEM brands and our own DHS Quality Parts line of professional aftermarket components. Need help finding the right part? Our team is available to confirm compatibility whenever you need it. Orders are processed fast to keep your jobs on track. We don't just sell parts. We keep you jobsite ready.
Questions? Contact our team at [email protected] or 866-611-9369 — DHS Equipment is here to help you maintain peak performance.
