The Wacker Neuson 5200021836 Key is a genuine OEM component designed for the APT4T and APT4S series self-priming trash pumps. As a direct OEM part, it is manufactured to the exact specifications required for proper fit and function across multiple APT4T and APT4S configurations, including Electric Brake, Surge Brake, and Cold Weather variants. Whether you are servicing a standard APT4S Pump with Skid or a Cold Weather-equipped APT4T, part number 5200021836 is the correct factory replacement. Stocking the right key keeps your pump drivetrain secure and your equipment operating as intended.
Key Features
- Genuine OEM Construction — Manufactured to exact dimensional tolerances for positive engagement and secure torque transfer at the shaft interface.
- Drop-In Replacement — Slots directly into the original keyway without alteration, restoring the connection between shaft and driven component as originally assembled.
- Broad APT Series Fitment — Compatible with APT4T Electric Brake, APT4T Surge Brake, APT4T Cold Weather, APT4S with Skid, and APT4S Cold Weather variants.
- Drivetrain Integrity — A correctly seated key prevents shaft slippage under load, ensuring the pump impeller maintains full rotational drive and consistent flow output.
- Verified by Part Number — Sourced directly from Wacker Neuson under part number 5200021836, eliminating guesswork when ordering for multiple APT pump configurations.
A key is a small, precision-machined component that sits in a slot — called a keyway — cut into both a rotating shaft and the hub of a driven component such as an impeller or pulley. It locks the two parts together rotationally so that torque from the engine transfers cleanly to the pump end without slipping. When a key shears or wears, the shaft spins freely inside the hub, the driven component stops turning, and the pump loses output entirely — even though the engine continues to run. Replacing a worn or sheared key with the correct OEM part restores full mechanical engagement and prevents accelerated wear to the surrounding keyway surfaces.
Part Details
| Part Number | 5200021836 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Key |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT4T Pump, Electric Brake, Cold Weather | APT4T CW | 5200019793, 5200019792 |
| APT4T Pump, Surge Brake | APT4T | 5200019643, 5200019644 |
| APT4S Pump w/Skid, Cold Weather | APT4S CW | 5200019798 |
| APT4S Pump w/Skid | APT4S | 5200018977 |
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.
