HYDBK4 | Hydraulic Motor Pump Base Kit 4 with Mounting Hardware

HYDBK4 | Hydraulic Motor Pump Base Kit 4 with Mounting Hardware | Heavy-Duty Base

HYDBK4 is the base kit for the big end of the compact world: Annovi Reverberi’s heavy-duty mounting platform built around a 14″ × 19″ × 1-5/8″ zinc-plated 10-gauge steel plate reinforced with two welded rib supports, a cast iron hydraulic motor mount, and an L100 flex drive coupler — pre-drilled for AR’s XW and SXW series pumps. Everything about it is sized up from the smaller kits for one reason: the pumps and motors it carries hit harder. Bigger displacement motors, higher horsepower through the coupling, more reciprocating mass on the plate — and the HYDBK4 answers each with structure: ribs against flex, cast iron against motor torque reaction, and the larger L100 coupling with the torque capacity the duty demands. Rubber isolation feet and mounting hardware are included; pump, motor, and accessories are sold separately.

This is the base that keeps a serious build from vibrating itself into maintenance tickets. A flat plate that shrugs off a 6-horsepower assembly will drum and work-harden under a 20-plus horsepower one; the welded ribs turn the HYDBK4’s plate into a beam, and the cast iron mount holds the motor’s centerline rigid against every pressure spike the pump sends back up the coupling.

HYDBK4 Specifications

• SKU: HYDBK4
• Configuration: Heavy-duty hydraulic base kit — cast iron motor mount with flex drive coupler
• Base Plate: 14″ × 19″ × 1-5/8″, zinc-plated 10-gauge steel with two welded rib supports
• Pump Compatibility: AR XW and SXW series pumps
• Motor Compatibility: HYDM329M, HYDM390M, or HYDM433M
• Drive: L100 flex drive coupler
• Motor Mount: Cast iron
• Included: Rubber feet and miscellaneous mounting hardware
• Not Included: Pump, motor, and accessories — sold separately

Sized for the Big Motor Class

The HYDBK4’s compatible motors are AR’s heavy hitters — the 33.4cc HYDM329M, the 39cc HYDM390M, and the 71cc HYDM433M, the 7/8″-shaft (and SAE-flanged, on the 433M) class that turns XW and SXW pumps at full duty from high-flow hydraulic systems. These are the motors whose torque justifies the cast iron mount and whose oil appetite pairs with real truck and machine circuits; WSHPWR will run the displacement-versus-oil-flow math for your system and name the motor before you order the set.

The L100 Coupling

Stepping up from the L095 of the lighter kits, the L100 jaw coupling carries the torque of this power class through the same forgiving architecture: two hubs, an elastomer spider absorbing plunger-stroke pulsation and routine misalignment, and mechanical independence between pump and motor — either dismounts for service without disturbing the other. The spider is the designed wear part, replaceable in minutes, standing guard over shafts, bearings, and seals that are not.

Built Like Infrastructure

Between the ribbed plate, the cast mount, and the coupling, the HYDBK4 assembles into a unit that installs like equipment rather than a project: one bolted assembly craned or two-manned into the truck body or skid, isolated on its rubber feet, with service access planned instead of improvised. Fleets running XW-class hydraulic wash and jetting systems standardize on this base for exactly that repeatability — every build identical, every spare interchangeable.

Installation Notes

Confirm the pump’s series and the motor’s shaft against the compatibility lists before ordering. Set both coupler hubs to the L100 gap specification, seat the spider fully, and torque set screws on clean shafts. Mount the HYDBK4 through its rubber feet to structure worthy of the assembly’s mass, verify motor rotation before first pressurization, plan hose routing around the pump’s service side, and put the coupler spider on the same inspection schedule as pump seals.

HYDBK4 Key Features & Applications

• 14″ × 19″ rib-reinforced zinc-plated base — structure sized for the power it carries.
• Cast iron motor mount holds the big-motor centerline rigid against torque reaction.
• L100 flex coupler with the torque capacity of the class; two-minute spider service.
• Pre-drilled for XW and SXW series pumps; fits HYDM329M, HYDM390M, and HYDM433M motors.
• Rubber isolation feet and mounting hardware included — one order, one assembly.
• Ideal for high-horsepower hydraulic wash and jetting builds, XW/SXW-class truck and skid systems, and fleets standardizing heavy drive assemblies. Motor-included version available: HYDBK4M.