The Wacker Neuson Piston Ring Set is a genuine OEM component designed for the APT4S and APT4T pump series, including standard, cold weather, surge brake, and electric brake configurations. As a factory-sourced part, this ring set meets the original design tolerances specified for these pumps, helping restore proper compression and oil control to the engine. It fits across the full range of APT4S and APT4T models, making it a practical go-to for scheduled engine rebuilds or compression-loss repairs on this pump family.
Key Features
- OEM Compression and Oil Control Tolerances — Manufactured to the exact ring gap and tension specifications of the original engine design, ensuring proper cylinder sealing rather than an approximate fit.
- Direct Engine Rebuild Replacement — Drops into the existing piston grooves without reworking or resizing, streamlining the rebuild process on APT4S and APT4T engines.
- Broad APT Series Coverage — Compatible with APT4S and APT4T pump models across standard, cold weather, surge brake, and electric brake variants, covering the full current lineup.
- Restores Lost Compression — Worn piston rings allow combustion gases to bypass the piston, robbing the engine of power and increasing oil consumption. Fresh rings bring compression back to operating spec.
- Genuine Wacker Neuson OEM Part — Sourced directly through the Wacker Neuson parts program, so you get the same ring set the pump left the factory with — not an approximation of it.
Piston rings seal the gap between the piston and the cylinder wall, serving two critical jobs: keeping combustion pressure above the piston where it belongs, and controlling how much oil travels up from the crankcase. When rings wear or break, compression drops, the engine loses pulling power, oil burns off faster than it should, and exhaust smoke increases. Replacing the piston ring set during an engine overhaul or in response to those symptoms restores cylinder sealing and oil management, returning the pump engine to its designed operating condition.
Part Details
| Part Number | 5200020065 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Piston Ring Set |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| APT4S Pump w/Skid | APT4S | 5200018977 |
| APT4T Pump, Surge Brake | APT4T | 5200019643, 5200019644 |
| APT4T Pump, Surge Brake, Cold Weather | APT4T CW | 5200019792, 5200019793 |
| APT4S Pump w/Skid, Cold Weather | APT4S CW | 5200019798 |
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.
