HYDM440M Hydraulic Motor | 4.40 cid Marzocchi

HYDM440M Hydraulic Motor | 4.40 cid Marzocchi

• HYDM440M is a Marzocchi external-gear hydraulic motor used as a
  direct cross-reference substitute for AR422741.
• Displacement: 4.40 in³/rev (≈72 cc/rev) for confident starting
  torque and smooth, steady running.
• Sized for mid- to larger-frame Annovi Reverberi (AR) triplex plunger
  pumps where reliable speed control, compact packaging, and predictable
  alignment matter.
• Mounted with the pump on a shared rigid base so shafts share the
  same centerline, reducing side loads on bearings and seal packs and helping
  assemblies run cooler, quieter, and longer than belt systems.
• Close-coupled geometry preserves access to the coupling, oil sight glass, and
  vented dipstick so a single technician can perform coupling checks, oil changes,
  and torque verification with common tools.
• Ideal where hydraulic power is present and space is tight—trailers and service
  bodies, enclosed vans, plant carts, rental fleets, and contractor rigs.

Hydraulic Motor & Ports

• Motor type & brand: Marzocchi external-gear (LSHT) motor,
  compact round-body form factor, 4.40 in³ / 72 cc displacement for high-torque
  pump drives.
• Typical hydraulic ports:
  SAE-12 ORB (3/4″) pressure/return plus
  SAE-8 ORB (1/2″) case drain when the build requires it
  (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 Manufacturer, Ports & Warranty

• Pump manufacturer: Annovi Reverberi (AR)—industry leader in
  quality since 1958; pumps engineered and made in Modena, Italy.
• AR pumps ship with crankcase oil installed and include a vented dipstick and
  sight glass for quick pre-start checks.
• Typical AR manifolds in this class:
  • XWL50.20 class (≈13 GPM @ 3000 PSI):
    1″ F-BSPP inlet / 1/2″ F-BSPP outlet.
  • RTX60 / RTX70 frames (≈15.8 GPM @ 4350 PSI; ≈18.5 GPM
    @ 2900 PSI): 1″–1¼” F-BSPP inlet / 1/2″ F-BSPP
    outlet.

  Adapters to NPT are readily available—always verify porting on the exact pump
  selected.

• Warranty: AR water end carries a
  5-year limited, conditional warranty; coverage requires proper
  hydraulic and water-side installation, correct filtration and lubrication, and
  operation within published limits (seals and valves are consumables).

Integration Checklist HYDM440M (Shop-Ready)

• Match motor displacement and available hydraulic flow/pressure to target pump
  speed:
  rpm ≈ 231 × hydraulic gpm ÷ motor displacement (in³).
• Confirm torque:
  lb-in ≈ displacement (in³) × psi ÷ 6.283.
• Plan power:
  hydraulic hp ≈ gpm × psi ÷ 1714, then apply realistic
  efficiency for true shaft power.
• Set upstream system reliefs correctly for your duty class.
• Specify 10–25 μm return filtration with an adequate β-rating.
• Size reservoir for heat rejection (practical rule:
  2–3× total system flow) and add an oil cooler for hot
  climates, prolonged bypass, or continuous duty.
• Water side: keep suction short, straight, and oversize from a flooded feed; use
  anti-collapse suction hose and a coarse inlet strainer to protect volumetric
  efficiency and prevent cavitation.
• Install an adjustable unloader and correctly sized high-pressure relief; add a
  glycerin-filled gauge for commissioning/diagnostics and a thermal relief on the
  bypass loop for extended gun-closed operation.
• Verify hose bend radii on suction, pressure, and bypass runs; never overspeed
  the pump or run it dry; confirm seal and O-ring compatibility when using
  detergents or hot water.

HYDM440M Hydraulic Motor | 4.40 cid Marzocchi

Applications & Benefits

• Applications: mobile wash skids on service trucks and trailers; heavy-equipment
  yards and rental turn-backs; municipal/DOT fleet and wastewater maintenance;
  marine/tug-boat and dock washdown; food & beverage sanitation and packaging
  rooms (observe local hygienic standards); agriculture and ranch equipment wash;
  conveyor and parts-cleaning cells; general plant maintenance and contractor
  rigs.
• Direct-drive HYDM440M advantages: smoother torque for stable pressure and calm trigger
  cycling; no belts to tension, no belt dust, and less guard bulk.
• Alignment-stable geometry helps extend seal and bearing life, while compact
  footprint and predictable hose routing support clean, repeatable OEM builds.
• In summary, HYDM440M (4.40 in³ / 72 cc) is a drop-in Marzocchi
  substitute for AR422741 that delivers high torque, smooth
  speed, and alignment-friendly mounting for AR triplex pumps—supporting compact,
  professional hydraulic-powered pressure-wash packages with long component life.