The Multiquip 12279H2301 is a genuine OEM Rear Crankshaft Oil Seal designed for C30HDNI and C30HDN series Mayco concrete pumps, including the C30HDNI Precision and C30HDNI Zenith variants. As a direct OEM replacement, this seal is manufactured to the same material grade and dimensional tolerances as the original component, ensuring a correct installation without guesswork. Sourced directly from Multiquip, part 12279H2301 is the confirmed correct seal for these cycloidal-drive pump models.
Key Features
- OEM-Grade Seal Material — Manufactured to the original compression rating and lip profile, maintaining proper contact with the crankshaft surface to prevent oil migration.
- Direct-Fit Replacement — Dimensioned to seat correctly in the rear crankcase housing of C30HDNI and C30HDN pumps with no modification to the bore or shaft.
- Broad Variant Coverage — Fits C30HDNI, C30HDN, C30HDNI Precision, and C30HDNI Zenith models, making it the go-to seal across the C30 Mayco pump family.
- Prevents Crankcase Oil Loss — A correctly seated rear crank seal keeps oil where it belongs, protecting internal engine components from running dry and preventing contamination of the pump mechanism.
- Fuel and Oil System Safety — A failed crankshaft seal allows oil to reach hot engine surfaces, creating a fire and smoke hazard on the jobsite; replacing it promptly restores safe operating conditions.
A rear crankshaft oil seal sits at the back of the engine crankcase and forms a dynamic barrier between the rotating crankshaft and the outside environment. Its job is to contain engine oil within the crankcase while preventing dirt, debris, and moisture from entering. When this seal wears, hardens, or cracks, oil begins to leak past the crankshaft journal — leading to low oil levels, contamination of surrounding components, and the risk of engine damage if left unaddressed. Replacing the seal at the first sign of weeping or oil accumulation at the rear of the engine is the most cost-effective way to protect the pump's powerplant.
Part Details
| Part Number | 12279H2301 |
|---|---|
| Brand | Multiquip |
| Part Type | Genuine OEM |
| Description | Rear Crankshaft Oil Seal |
Compatibility & Fitment
| Name | Model |
|---|---|
| Mayco Pumps | C30HDNI |
| Mayco Pumps | C30HDN |
| Mayco Pumps | C30HDNI Precision |
| Mayco Pumps | C30HDNI Zenith |
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.
