HYDBK4M Hydraulic Base Kit 4 | Motor Included

HYDBK4M Hydraulic Base Kit 4 | Motor Included | Heavy-Duty Drive Foundation

HYDBK4M is the heavy base kit finished: everything in Annovi Reverberi’s HYDBK4 — the 14″ × 19″ × 1-5/8″ zinc-plated 10-gauge plate with two welded rib supports, cast iron hydraulic motor mount, L100 flex drive coupler, rubber isolation feet, and mounting hardware — with the heavy-class hydraulic motor included in the box, factory-matched from the Marzocchi HYDM329M/390M/433M class the kit is built around and confirmed against your pump and circuit at order. Add the XW- or SXW-class pump and the build is complete: one order, one delivery, one assembly that bolts together with the drive already solved.

That completion is the product. The bare HYDBK4 serves builders who own or specify their own motor; the HYDBK4M serves everyone who would rather not run that sourcing project at all — because at the heavy class, “source a motor” means displacement math against the circuit, shaft and coupler-bore verification against the L100, pressure ratings against the relief plan, and lead time against the schedule. The kit deletes the whole list: the motor arrives sized, the coupler hubs match, and the cast iron mount was designed for exactly what lands on it.

HYDBK4M Specifications

• SKU: HYDBK4M
• Configuration: Heavy-duty hydraulic base kit with hydraulic motor included
• Base Plate: 14″ × 19″ × 1-5/8″, zinc-plated 10-gauge steel with two welded rib supports
• Motor Mount: Cast iron
• Drive: L100 flex drive coupler
• Included Motor: Marzocchi heavy-class gear motor (HYDM329M/390M/433M class, 7/8″ shaft) — exact displacement factory-matched to your pump and hydraulic circuit, confirmed at order
• Pump Compatibility: AR XW and SXW series pumps — pre-drilled patterns
• Included: Rubber feet and miscellaneous mounting hardware
• Not Included: Pump and accessories — sold separately

Why the Motor Belongs in the Box

Heavy-class drive sourcing is where good builds stall. The motor must land the pump at 1450 RPM on the circuit’s honest flow — RPM ≈ 231 × hydraulic GPM ÷ displacement (in³) — carry the pump’s horsepower inside its continuous pressure rating, present a 7/8″ shaft the L100 hub actually fits, and arrive before the truck’s build slot closes. Miss any one and the project waits; guess any one and the system underperforms for years. The HYDBK4M moves that entire decision to WSHPWR’s counter: tell us the pump and the circuit’s flow, pressure, and relief numbers, and the kit ships with the displacement the arithmetic actually calls for — the 2.01 cid class for the lighter heavy duties, the 2.38 cid workhorse for the full 13 GPM tier, or the largest frame where the pump demands it.

The Structure Underneath

Everything the bare HYDBK4 brings carries over, because at 20-plus horsepower of reciprocating drive the structure is half the product. The welded ribs turn the plate into a beam that shrugs off the drumming a flat sheet would amplify; the cast iron mount holds the motor’s centerline rigid against torque reaction on every pressure spike; the L100 coupler transmits the class’s torque through an elastomer spider that absorbs plunger pulsation, forgives real-world alignment, and separates pump from motor for independent service — a two-minute insert swap standing guard over shafts and bearings that are not. Rubber feet isolate what remains from the deck the assembly bolts to.

One Order, One Assembly

Ordered with its pump, the HYDBK4M arrives as a coordinated set: pre-drilled patterns matching the pump’s feet, coupler hubs matching both shafts, motor matched to the duty. Assembly is a bench afternoon — set the hubs to the L100 gap specification, seat the spider, torque the hardware, mount through the feet — and the finished unit installs as one piece: craned or two-manned into the truck body or skid, hoses connected, running. Fleets standardizing heavy wash and jetting builds specify the kit for exactly that repeatability: every truck identical, every spare interchangeable, every build a known quantity instead of a fabrication project.

Installation & Operation Notes

Confirm rotation at commissioning — the included gear motor is 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 (documented with your order), specify 10–25 micron return filtration, route the return generously to tank, plumb the case drain above reservoir oil level, and engineer oil cooling for continuous duty at this power class. Verify pump speed at first run by the flow-÷-displacement math or a phototach, recheck coupler and base fasteners after initial run-up, and put the L100 spider on the same inspection schedule as pump seals.

Quality Assurance & Maintenance

Every HYDBK4M ships with its motor’s Marzocchi factory testing, the kit’s fitment verified, and the pairing confirmed against your stated pump and circuit before anything leaves. Maintenance afterward splits cleanly: the pump follows AR’s standard schedule; the motor asks only clean, filtered oil behind a correct relief; the base asks a fastener check and a glance at the spider. The heavy build that installs like equipment maintains like it too.

HYDBK4M Key Features & Applications

• The complete HYDBK4 heavy base — ribbed 14″ × 19″ plate, cast iron mount, L100 coupler, feet, hardware — with the motor in the box.
• Marzocchi heavy-class motor factory-matched to your pump and circuit, confirmed at order.
• Deletes the heavy-drive sourcing project: displacement, shaft, coupler fit, and lead time all solved.
• Pre-drilled for XW and SXW series pumps — add the pump and the build is whole.
• One bolted assembly for installation and service; fleet-repeatable builds, interchangeable spares.
• Ideal for XW/SXW-class truck and skid builds, production wash and jetting systems, fleet standardization programs, and any heavy build that should arrive matched instead of sourced.