HYDM403 Hydraulic Motor | 2.46 cid Parker

Overview

• HYDM403 is a Parker low-speed/high-torque (LSHT) hydraulic motor
  with 2.46 in³/rev (≈40.3 cc/rev) displacement.
• Delivers strong starting torque and smooth, steady running for
  mid-frame Annovi Reverberi (AR) triplex plunger pumps where precise
  speed control, compact packaging, and predictable alignment matter.
• Mounted with the pump on a shared rigid base so the motor and pump
  share a true centerline, reducing side loads on bearings and seal packs so assemblies
  run cooler, quieter, and longer than belt drives.
• Close-coupled layout leaves room for short, direct suction, tidy pressure and bypass
  routing, and perimeter space for an unloader block without tight bends.
• Technicians retain clear access to the coupling, oil sight glass, vented dipstick,
  and fasteners for single-tech preventive maintenance.

Hydraulic Motor & Ports

• Motor type & brand: Parker LSHT hydraulic motor
  (external-gear or gerotor family depending on build).
• Displacement chosen for mid-frame AR duty with calm trigger cycling and stable
  working pressure.
• Typical hydraulic ports: SAE-12 ORB (3/4 in) pressure and return
  plus a SAE-8 ORB (1/2 in) case drain – verify on the supplied motor.
• Observe A/B port orientation for correct rotation and route the case drain above
  reservoir oil level to prevent aeration.
• Size hose IDs generously and respect bend radii on all lines to avoid restriction
  and heat.

Pump Ports & Example Pairings

• Pump manufacturer: Annovi Reverberi (AR) – pumps engineered and
  made in Modena, Italy.
• Mid-frame RK/RK21xx manifolds commonly:
  1/2 in F-BSPP inlet and 3/8 in F-BSPP outlet.
• XWL/RTX mid-frames typically:
  1 in F-BSPP inlet and 1/2 in F-BSPP outlet.
• Adapters to NPT are readily available; keep suction short, straight, and oversize
  from a flooded feed and use anti-collapse suction hose plus a coarse inlet strainer.
• Performance pairing examples (select per duty and never overspeed the pump):
  • RK2120 ≈ 5.5 GPM @ 2900 PSI
  • XWL50.20 ≈ 13 GPM @ 3000 PSI
  • RTX60 ≈ 15.8 GPM @ 4350 PSI
  • RTX70 ≈ 18.5 GPM @ 2900 PSI

Integration Checklist & Sizing

• Match motor displacement and available hydraulic flow/pressure to target pump speed:
  rpm ≈ 231 × hydraulic gpm ÷ motor displacement (in³).
• Confirm torque with
  lb-in ≈ displacement (in³) × psi ÷ 6.283.
• Confirm power with
  hp ≈ gpm × psi ÷ 1714, then apply realistic efficiencies to
  validate shaft power.
• Set upstream reliefs correctly for your duty class and include a case drain if the
  motor specification calls for it.
• Specify 10–25 μm return filtration with an adequate beta rating and
  size the reservoir for heat rejection (rule of thumb: 2–3× total system
  flow).
• Add an oil cooler for hot climates, prolonged bypass, or continuous duty.
• Water side: add an adjustable unloader, a correctly sized high-pressure relief,
  a glycerin-filled gauge for commissioning/diagnostics, and a thermal relief on the
  bypass loop for extended gun-closed operation.

Warranty & Ownership

• AR pumps ship with oil in the crankcase and include a vented dipstick and sight
  glass for quick pre-start checks.
• AR water ends carry a 5-year limited, conditional warranty.
• Proper hydraulic and water-side installation, correct filtration and lubrication,
  and operation within published limits are required for coverage.
• Seals and valves are normal wear items and treated as consumables.

Applications & Benefits

• Compact, belt-free package with alignment-stable geometry that helps extend seal
  and bearing life.
• Smooth LSHT torque for stable pressure and calm trigger cycling.
• Predictable hose routing supports repeatable OEM builds and fast pump swaps; no
  belt retensioning or belt dust.
• Ideal for mobile wash skids, service trucks, municipal/DOT fleets, wastewater and
  sanitation rigs, heavy-equipment yards and rental turn-backs, and food &
  beverage sanitation and process rinse (follow local standards).
• Also suited to marine and tug-boat dock washdown, agriculture and ranch equipment
  wash, conveyor and parts-cleaning cells, plant carts, and contractor rigs seeking
  a tidy, professional hydraulic motor–driven AR pump solution.