HYDM403 Hydraulic Motor | 2.46 cid Parker

HYDM403 Hydraulic Motor | 2.46 cid Parker | The Parker Heavy-Class Option

HYDM403 brings Parker to the heavy end of the motor line: a 2.46 in³ (40.3cc) Parker gear motor serving the same workhorse band as the line’s 2.38 cid Marzocchi — roughly 27 horsepower of pump drive at 1450 RPM — for the operations whose hydraulic world already speaks Parker. Parker Hannifin is the largest motion-and-control company on earth; its motors, fittings, and filtration run through a huge share of North American truck upfits and industrial systems, and for fleets standardized on that ecosystem, the HYDM403 keeps the wash system inside it: familiar build behavior, familiar distribution, one brand across the machine and the drive it powers.

The duty band is the 13 GPM tier and its neighbors at full published ratings: XWL 50.20-class platforms at their 25 HP demand, SXW heavy washdown, and the strong strip-and-production systems that consume the mid-teens GPM of oil this displacement drinks. The slightly larger swallow than its Marzocchi counterpart trades a touch more flow for a touch less working pressure at identical duty — in practice the classes overlap completely, and the honest selection criterion is the one on the shop’s shelves already.

HYDM403 Specifications

• SKU: HYDM403
• Manufacturer: Parker Hannifin
• Type: External gear hydraulic motor — heavy-frame class
• Displacement: 2.46 in³ (40.3cc) per revolution
• Oil Flow for Pump-Speed Drive: Approximately 15.4 GPM at 1450 RPM
• Pressure and Speed Ratings: Parker heavy gear class — confirm the build sheet with WSHPWR for your duty point
• Drive Duty: Approximately 27 HP of pump drive at 1450 RPM
• Shaft: 7/8″ class
• Ports: SAE O-ring class

Sizing the HYDM403

The selection line — RPM ≈ 231 × hydraulic GPM ÷ 2.46 — lands the pump at 1450 RPM on roughly 15.4 GPM of oil. Torque follows pressure — T ≈ 2.46 × ΔPSI ÷ 6.283 — carrying the ~27 HP tier at heavy gear-class working pressures with margin over the 25 HP platforms that define the band: the pairing that works at 85% of capability instead of 100% is the pairing that lasts. Verify your circuit’s honest, sustained delivery at working pressure — this class consumes 15-plus GPM all shift, and brochure numbers that sag under load are the classic heavy-system disappointment — then call WSHPWR with flow, pressure, and target pump for the confirmed match and the Parker build sheet.

The Parker Ecosystem Play

Brand standardization is an underrated hydraulic specification, and nowhere more than at the heavy class where downtime bills by the hour. A fleet whose trucks already run Parker pumps, Parker hose, and Parker filtration knows exactly how the brand behaves at temperature, where its distribution sits on a Saturday, and what its service documentation looks like — and the HYDM403 extends all of that to the wash drive instead of introducing a stranger. For mixed shops, it is simply the second qualified answer in the workhorse band: same duty coverage as the Marzocchi route, chosen by ecosystem, availability, and preference rather than performance difference.

Completing the Build

The HYDM403 lives in the heavy mounting world — the HYDBK4-class cast-iron-mount architecture and the adjustable HYDBK3 base (whose compatible-brand list names Parker explicitly) both serve it, with coupling and interface confirmed against your pump at order. As a repower it restores fielded Parker-motored systems with their original architecture intact: confirm the 7/8″-class shaft and mount against the installation, swap the component, resume production the same day. WSHPWR verifies fitment against your stated pump and circuit on every heavy-class order.

Installation & Operation Notes

Confirm rotation direction against your pump before plumbing — gear motors are direction-specific by port assignment, and at this torque a backward start is an expensive mistake. Set the circuit relief within the motor’s rating, specify 10–25 micron return filtration with an adequate beta rating, route the return generously to tank, and plumb any case drain above reservoir oil level to prevent aeration. Treat oil cooling as a design item at 27 horsepower of continuous drive, torque mounting hardware to spec on structure worthy of the assembly, and verify pump speed at commissioning by the flow-÷-displacement math or a phototach — the pump’s rated RPM governs the ceiling, always.

Quality Assurance & Maintenance

Every HYDM403 carries Parker’s factory testing and ships only after WSHPWR confirms the fitment against your stated pump and circuit. The ongoing program is gear-motor minimal at heavy scale: clean, filtered oil, a correct relief, periodic hose-end and drain-line inspection, cooling-system condition on the schedule — no internal service program. Protected that way, the motor routinely outlasts the wet ends it drives.

HYDM403 Key Features & Applications

• 2.46 cid Parker — the Parker-ecosystem answer in the heavy workhorse band.
• ~27 HP of pump drive at 1450 RPM on roughly 15.4 GPM of oil — margin over the 25 HP platforms.
• One brand across machine, hose, filtration, and now the wash drive.
• Suits the HYDBK3/HYDBK4 mounting architectures; Parker named in the adjustable base’s compatibility.
• The straight repower for fielded Parker-motored heavy systems.
• Ideal for XWL 50.20-class and SXW pump drives, Parker-standardized fleets, production wash and strip systems, and truck circuits carrying honest 15-plus GPM.