Wacker Neuson 5100050646 Filler Cap

The Wacker Neuson Filler Cap is a genuine OEM filler cap designed for the RD18, RD24, RD28, RD40, and RD45 series tandem rollers. Sourced directly from Wacker Neuson, this is the same part installed at the factory — built to the exact tolerances and material specifications required for correct sealing performance on these machines. It fits an extensive range of RD series configurations including standard, C, O, DPF, and electric variants, as well as ROPS and CAB versions of the RC110. Confirm your model number against the fitment list to ensure this is the correct cap for your machine.

Key Features

• OEM Sealing Integrity — Manufactured to the exact thread pitch and sealing surface specification required by Wacker Neuson, ensuring a leak-free closure every time the cap is seated.
• Direct Drop-In Replacement — Threads directly into the original filler neck without modification; matches the torque and retention characteristics of the cap it replaces.
• Broad RD Series Coverage — Compatible with RD18, RD24, RD28, RD40, and RD45 tandem roller families across standard, C, O, DPF, and electric configurations, plus RC110 ROPS and CAB models.
• Contamination Defense — A correctly seated filler cap keeps dirt, debris, and moisture out of the fluid reservoir, protecting internal components from premature wear caused by contamination.
• Fluid Loss Prevention — A worn or damaged filler cap can allow fluid to escape during operation, leading to low fluid levels and potential system damage; replacing it promptly keeps fluid levels stable and the machine operating correctly.

A filler cap seals the fluid reservoir fill point on the tandem roller, preventing fluid loss and blocking contaminants from entering the system during operation and storage. When the cap is cracked, cross-threaded, or missing its sealing element, fluid can escape or degrade due to contamination — both of which can cause accelerated wear or system failure in the roller's hydraulic or water-sprinkling circuit. Replacing a faulty filler cap with the correct OEM part is one of the simplest preventive maintenance steps an operator can take to protect the machine's long-term serviceability.

Part Details

Compatibility & Fitment

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.