The Multiquip 12035H9820 is a genuine OEM Piston Ring Set (OS=0.50 oversize) designed for Mayco C30HDNI and C30HDN series concrete pumps, including the C30HDNI Precision and C30HDNI Zenith variants. As a direct Multiquip OEM component, part 12035H9820 is manufactured to the same specifications as the original rings installed at the factory, ensuring a correct fit during engine rebuild or oversize bore service. This ring set is the right choice when cylinder walls have been bored or honed to the 0.50mm oversize dimension, restoring proper compression and oil control to the engine. DHS Equipment stocks this genuine OEM part to help keep your Mayco concrete pump working at full capacity.
Key Features
- Genuine OEM Oversize Specification: — Manufactured to exact OS=0.50 oversize tolerances, ensuring correct ring-to-bore clearance after a 0.50mm overbore — not a universal fit ring that requires guesswork.
- Complete Ring Set: — Includes the full complement of piston rings for one piston, covering compression and oil control rings so you have everything needed for a proper engine rebuild in a single part number.
- Direct Engine Rebuild Fitment: — Engineered specifically for the C30HDNI, C30HDNI Precision, C30HDNI Zenith, and C30HDN Mayco concrete pump engine assemblies, dropping in without modification to the piston or connecting rod.
- Compression and Oil Seal Integrity: — Correctly sized rings restore combustion chamber sealing and control oil consumption; worn or improperly sized rings cause blow-by, power loss, and excessive smoke that compromise pump output.
- Fuel Efficiency and Power Recovery: — Proper ring seal ensures the engine delivers its rated output to drive the concrete pump, so material flow rates and pumping distance are maintained after a rebuild.
Piston rings form the dynamic seal between the piston and the cylinder wall inside an internal combustion engine. They serve two critical roles: the compression rings prevent combustion gases from escaping past the piston, maintaining the pressure needed to generate power, while the oil control ring scrapes excess lubrication oil from the cylinder wall and returns it to the crankcase. When rings wear or the cylinder is bored oversize to correct wear, standard-dimension rings will no longer seal correctly — an oversize ring set like the 12035H9820 at OS=0.50 is required to match the enlarged bore and restore full engine performance. Running an engine with worn or incorrect rings leads to reduced compression, increased oil consumption, hard starting, and ultimately shortened engine life.
Part Details
| Part Number | 12035H9820 |
|---|---|
| Brand | Multiquip |
| Part Type | Genuine OEM |
| Description | Piston Ring Set OS=0.50 |
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.
