The Wacker Neuson 5100030251 is a genuine OEM Water Tank Cap designed for the RD7 and RD27 series tandem rollers. This is a direct factory replacement sourced from Wacker Neuson, ensuring the correct fit and seal for the water system on your walk-behind and ride-on roller. Compatible models include the RD7A, RD7H, RD7He, RD7Ye, RD27-100, and RD27-120, covering a wide range of both standard and Pro configurations. When a water tank cap is cracked, missing, or no longer sealing properly, the drum wetting system can lose pressure or allow contamination — replacing it promptly with part 5100030251 keeps your water system functioning as intended.
Key Features
- Genuine OEM Seal Integrity — Manufactured to Wacker Neuson's original specification, this cap delivers the correct thread engagement and sealing surface to maintain a closed water system without leaks or pressure loss.
- Drop-In Replacement — Threads directly onto the water tank filler neck as originally installed, with no modification to the tank or water system assembly needed.
- Broad RD7 and RD27 Series Coverage — Fits the RD7A, RD7H, RD7He, RD7Ye, RD27-100, and RD27-120 across multiple serial number ranges, including Tier 4 Final and walk-behind configurations.
- Protects Drum Wetting System Performance — A properly sealing cap keeps the water supply pressurized and free of debris, allowing the drum wetting nozzles to deliver consistent asphalt release during paving passes.
- Contamination Prevention — Keeps dirt, dust, and job site debris out of the water tank, protecting nozzles and water lines from premature clogging or damage.
The water tank cap seals the filler opening on the roller's onboard drum wetting system, which sprays water onto the compaction drums to prevent fresh asphalt from sticking during rolling operations. A secure, airtight cap is essential for maintaining consistent water flow to the drum spray bars — without it, the system can lose prime, draw in contaminants, or fail to deliver water evenly across the drum surface. A worn or missing cap may seem like a minor issue, but it can lead to asphalt pickup on the drums, reduced compaction quality, and accelerated wear on downstream water system components.
Part Details
| Part Number | 5100030251 |
|---|---|
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Water Tank Cap |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| RD7 Tandem Roller | RD7A | 5100017196, 5200015243, 5200015246 |
| RD7 Tandem Roller | RD7He | 5100017193, 5100017194, 5200015241, 5200015244, 5100038031, 5100018451 |
| RD7 Tandem Roller | RD7H | 5100017195, 5100017338, 5200015242, 5200015245 |
| Hydrostatic Vibratory Roller | RD27-120 | 5200005879, 5200014922, 5200014923, 5200014869, 5200023557, 5200023555, 5200024441, 5200005877, 5200021389 |
| Hydrostatic Vibratory Roller | RD27-100 | 5200005878, 5200014868, 5200023556, 5200023554, 5200021387, 5200005876 |
| RD7Ye Tandem Roller | RD7Ye | 5100027116, 5100027117, 5100038032, 5100048340 |
| Water System cpl. | Water System cpl. | 5100045168 |
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.
