The Wacker Neuson Valve Lock Nut is a genuine OEM component designed for a wide range of Wacker Neuson equipment, including MG3 and MG5 portable generators, ML440, ML425, ML240, and ML225 light towers, MP15 and MP70 single direction plates, MPU 29 reversible plates, MDP3 trash pumps, MFS12 and MFS14 floor saws, MFP1.5 and MFP2 fire pumps, and MD3.5 modular internal vibrators. Sourced directly through the Wacker Neuson OEM supply chain, this valve lock nut is manufactured to the exact tolerances required for proper valve retention and secure locking performance across every compatible application. With fitment spanning dozens of confirmed machine configurations, the is a high-demand service part used across multiple Wacker Neuson equipment families. Keep a spare on hand to stay ahead of routine maintenance across your fleet.
Key Features
- Genuine OEM Thread and Torque Spec Compliance — Manufactured to Wacker Neuson's exact dimensional and material standards, ensuring the valve lock nut engages and holds under the correct clamping load without backing off under vibration or thermal cycling.
- Direct Drop-In Replacement — Matches the original mounting thread pattern and hex profile, so installation requires no rework, chasing, or adapting — it seats and torques exactly as the factory part does.
- Broad Fleet Coverage — A single part number that fits MG3 and MG5 generators, ML225 through ML440 light towers, MP15 and MP70 compaction plates, MDP3 trash pumps, MFS12 and MFS14 floor saws, MPU 29 reversible plates, and more — making it a practical stock item for mixed Wacker Neuson fleets.
- Secure Valve Retention Under Working Conditions — A properly functioning valve lock nut holds valve adjustment in place during operation; a worn or loosened nut allows valve clearance to shift, leading to performance loss, accelerated wear, and potential engine damage.
- Fuel System Integrity — Correct valve locking is critical to maintaining consistent compression and fuel combustion; using the correct OEM-spec nut helps ensure the engine's valve train operates within its designed parameters safely and consistently.
A valve lock nut secures the valve adjustment mechanism — typically a rocker arm adjustment screw or valve stem adjuster — and prevents it from moving out of its set position during engine operation. Once a technician sets valve clearance to specification, the lock nut is tightened down to hold that setting in place against the continuous vibration and heat generated by the engine. If the lock nut loosens, stretches, or strips, valve clearance drifts out of spec, which can cause hard starting, reduced power, excessive wear on valve train components, and in severe cases, valve contact with the piston. Replacing a worn or damaged valve lock nut with the correct OEM part — like the Wacker Neuson 5000405102 — restores proper locking function and protects the integrity of the valve adjustment.
Part Details
| Part Number | 5000405102 |
|---|---|
| Old Part Number | 0405102 |
| Brand | Wacker Neuson |
| Part Type | Genuine OEM |
| Description | Valve Lock Nut |
Compatibility & Fitment
| Name | Model | Machine Number |
|---|---|---|
| MP15 | MP15 | 5000630131, 5000630227 |
| Light Towers | ML440 | 5000630117, 5000630204, 5000630323, 5000630324, 5000630325, 5000630327 |
| Light Towers | ML240 | 5000630118, 5000630205, 5000630326 |
| Light Towers | ML425 | 5000630119, 5000630206 |
| Light Towers | ML225 | 5000630120, 5000630207 |
| Modular Internal Vibrators | MD3.5 | 5000630242 |
| Single Direction Plate | MP70 | 5000630243 |
| Single Direction Plates | MP15-CE | 5000630338 |
| Portable Generators | MG5 | 5000630137, 5000630143, 5000630233, 5000630254, 5000630224, 5000630229, 5000630237, 5000630239, 5000630252, 5000630308, 5000630310, 5000630334 |
| Trash Pumps | MDP3 | 5000630140, 5000630144, 5000630176, 5000630177 |
| Reversible Plates | MPU 29 | 5000630141, 5000630228 |
| Floor Saw | MFS14 | 5000630186, 5000630221 |
| Floor Saw | MFSX14 | 5000630246 |
| Portable Generators | MG3 | 5000630142, 5000630135, 5000630256, 5000630225, 5000630230, 5000630234, 5000630238, 5000630240, 5000630253, 5000630309, 5000630311, 5000630335 |
| Floor Saw | MFS12 | 5000630187, 5000630220 |
| Portable Generators | MG3sd | 5000630201, 5000630215, 5000630235 |
| Portable Generators | MG5sd | 5000630202, 5000630214, 5000630236 |
| MG5 Generator | MG5d | 5000630211 |
| MG3 Generator | MG3d | 5000630213 |
| Fire Pump | MFP1.5 | 5000630258 |
| Fire Pump | MFP2 | 5000630259 |
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.
