W4443DLX 4400 PSI Pump GX390 Clear View Inlet

W4443DLX — Bertolini Deluxe Package | 4400 PSI | 4.3 GPM | Clear View Filter | 1″ Hollow Shaft

The W4443DLX is the top-of-line deluxe build of WSHPWR’s Bertolini pump package of the Bertolini W4443 — a professional-grade triplex ceramic plunger pump WSHPWR bench tested, pre-lubricated, and shipped as a complete pressure system ready to mount. Every component in the W4443DLX — the pump, the integrated unloader, the thermal relief valve, the internal bypass circuit, and all fittings — is factory-plumbed, pressure-set, and WSHPWR bench tested before shipment. This is not an assembly kit. When the W4443DLX arrives, it is ready to bolt onto your engine, connect your water supply, drop the detergent hose into your soap bucket, and operate at 4400 PSI with chemical injection from the first startup — with the added confidence of a heavy-duty clear view inlet filter protecting every drop of water entering the pump.

What’s in the Box

• Clear View Dual-Port Brass Inlet Water Filter — Upgraded — The defining upgrade of the W4443DLX. This is not a standard inline filter. Machined from heavy-duty brass — no rust, no corrosion, thick-wall construction that holds up against side torque and rough handling. Features a stainless steel micron inner filter screen inside a transparent body that lets you inspect water clarity and filter condition at a glance without removing a single fitting. Dual 1/4″ side ports accommodate a return bypass hose for full recirculation circuit integration. Rated to 8 GPM and 180°F — the strongest see-through inlet filter available for this class of pump. Rinse, reassemble, and reinstall in under a minute. No tools required.
• SAE J609-1″ Flange with 4-Bolt and Lock Washer Kit — Everything needed for a seamless, rattle-free installation directly to your engine. Grade hardware included — nothing to source separately.
• Bertolini W4443 Triplex Ceramic Plunger Pump — WSHPWR bench tested and pre-lubricated with break-in oil. Bronze connecting rods, solid ceramic plungers, forged brass manifold with increased wall thickness, AISI 316 stainless steel valve assemblies, dual redundant V/U packing system, and oversized crankshaft bearings — factory-installed and factory-verified. 1″ hollow SAE J609-1″ shaft for direct Honda GX and compatible engine coupling. Ready to mount.
• Integrated Unloader — Built Into the Forged Brass Manifold — Factory-set and pressure-tuned to the 4.3 GPM / 4400 PSI operating duty point of the W4443DLX. The unloader is machined directly into the forged manifold pump assembly, providing smooth pressure regulation and stable output under varying flow conditions from the first startup. No aftermarket tuning required. Because the bypass circuit is internal and sealed within the manifold, there are no external bypass hoses, fittings, or junctions to loosen, leak, or service in the field — fewer connection points means fewer failure points.
• Self-Lubricating Internal Bypass — When the trigger gun closes, flow recirculates through the pump’s smooth internal bypass passage rather than deadheading in the head. The bypass passage is self-lubricating and engineered to dramatically reduce friction and heat build-up during the bypass function, protecting the seals and plungers during trigger-off intervals and extending pump life under continuous-duty cycling.
• Easy Start Feature — At engine startup, the bypass circuit opens and the pump starts against zero back pressure. The engine engages freely under no hydraulic load — recoil pull-starts require minimal effort and electric starters draw minimal current. Once the engine reaches operating speed, the bypass closes and the system builds to 4400 PSI. Easier starts on every pull. Less starter wear. Longer engine life. This is particularly valuable on Honda GX series engines and other recoil-start platforms where hydraulic back pressure at startup accelerates starter rope and pawl wear.
• Automatic Thermal Relief Valve (TRV) — Factory-Installed — The thermal sensing element continuously monitors bypass water temperature. When bypass water reaches 124–145°F, the TRV opens automatically — hot water exits through the relief port and ambient-temperature supply water flows in to replace it. When temperature returns to the safe operating range, the TRV closes automatically. No manual reset. No operator intervention required. The W4443DLX pump is thermally protected at all times — including during the extended idle intervals unavoidable in daily contractor and fleet washing operations.
• Fittings and Mounting Hardware — Every fitting and fastener required for installation onto contractor skids, trailer frames, fleet wash bays, and OEM gas engine systems. Organized in the box. Nothing to source separately.
• Factory Break-In Oil — Crankcase pre-filled at 0.16 U.S. gal with SynPower Gear Oil 75W-90. Oil sight glass and vented dipstick included for ongoing monitoring. After the break-in period (50–100 hours), replace with standard SAE 75W-90 — and never change it again. Lifetime oil for the life of the pump.
• Operator’s Manual and Service Schematics — Complete installation, startup, operating, and maintenance procedures with part numbers for every serviceable component.
• 16% Adjustable Chemical Injector — Factory-Installed — Downstream chemical injector with an adjustable soap-to-water ratio up to 16%. Draws detergent automatically whenever the trigger is pulled through the low-pressure circuit. Dial the draw rate in to match your detergent and the job at hand. Compatible with standard pressure washer soaps, degreasers, and detergents.
• DETHOSE-FIL6 — 6 ft Detergent Hose with Red Weighted Debris Filter — Six feet of chemical-resistant thermoplastic hose with an integrated red weighted filter that sinks to the bottom of the detergent container for consistent chemical pickup even as the tank empties. Captures debris and sediment before it reaches the injector, protecting valves and seals from abrasive particles.

Why the W4443DLX Uses an Integrated Unloader

The W4443DLX routes bypass flow through an unloader machined directly into the forged brass head, rather than bolting on an external bypass assembly. For contractor and industrial applications, this integrated design is the professional-grade choice — it is compact, factory-calibrated, and sealed within the manifold, with no external bypass hoses or junctions to loosen or leak under continuous duty.

The internal bypass passage is smooth and self-lubricating, engineered to dramatically reduce friction and heat build-up during the bypass function. When the trigger gun is closed, water recirculates through this internal circuit instead of deadheading in the pump head — keeping operating temperatures down, protecting the seals and plungers, and maintaining stable system pressure shift after shift. Fewer external connection points means fewer potential failure points for operations running multiple shifts, fleet washing programs, or skid systems where downtime is measured in lost revenue.

Performance

What’s Inside the W4443DLX Pump

• Forged Brass Manifold — Increased Wall Thickness — Engineered for higher operating temperatures and maximum rigidity under overpressure events. Houses the integrated unloader and internal bypass circuit.
• LowStressthread™ Valve Caps — Recessed O-ring design. Thread never contacts pressurized water. No Loctite required. Torque reduced by 40%.
• AISI 316 Stainless Steel Valve Assemblies — Mirror-finish, rapid-action check valves for corrosion resistance and maximum fluid dynamic efficiency.
• Dual Redundant V/U Packing System — Fabric-reinforced nitrile buna front seals with Inox-compatible rear seals. Self-energizing under pressure. Long service life under continuous-duty cycling.
• Solid Ceramic Plungers — High-grade ceramic for years of uninterrupted high-pressure performance. Smooth surface finish minimizes seal wear and maximizes volumetric efficiency.
• Bronze Connecting Rods (One-Piece) — Superior anti-friction performance, lower operating temperatures, and extended service life vs aluminum rods.
• Oversized Crankshaft Bearings — Extended service life under heavy and continuous-duty conditions.
• Forged Steel Crankshaft — Extended Length — Maximum structural rigidity for solid pump-to-engine coupling.
• Die-Cast Aluminum Crankcase — Anti-corrosion alloy with diamond-tool machined plunger guide surfaces and enhanced cooling fins.
• Integrated Unloader with Self-Lubricating Internal Bypass — Machined into the forged manifold, factory-set to 4400 PSI operating pressure. Smooth internal bypass reduces friction and heat during the bypass function.
• Automatic Thermal Relief Valve — Factory-installed. Activates at 124–145°F. Automatic reset. No operator intervention.

Specifications

W4443DLX vs W4443PI — What’s the Difference

The W4443DLX includes everything in the W4443PI — the integrated unloader with self-lubricating internal bypass, Easy Start feature, automatic thermal relief valve, 16% adjustable chemical injector, and DETHOSE-FIL6 detergent hose — plus the clear view dual-port brass inlet filter. For operators running contractor skids, trailer systems, or fleet wash bays where water quality varies and filter condition directly impacts pump life, the ability to inspect the inlet filter at a glance without shutting down the system is a meaningful operational advantage. On the W4443DLX, you see the problem before it becomes one.

Applications

• Contractor pressure washing skids and trailer systems
• Fleet and heavy equipment washing programs
• Honda GX engine direct-drive installations
• OEM gas engine skid builds
• Industrial and commercial washdown systems
• Multi-shift operations requiring continuous-duty reliability

W4443DLX — When You Want Everything and Then One More Thing

The W4443DLX is the most completely equipped pump package WSHPWR offers. It includes every component in the W4443PI — integrated unloader with self-lubricating internal bypass, automatic thermal relief valve, 16% adjustable chemical injector, DETHOSE-FIL6 detergent hose, Easy Start — plus the clear view dual-port brass inlet filter that no other pump package in this category includes. At $549 delivered, it costs less than assembling an equivalent system from components starting with a bare Comet or General Pump.

W4443DLX vs Build-Your-Own Equivalent

The Clear View Filter — The Detail That Separates Professionals

Every component in the W4443DLX serves a function. The clear view dual-port brass inlet filter is the one that separates contractors who prevent pump failures from contractors who react to them. Inlet contamination — debris, sediment, mineral scale — is the leading cause of premature packing wear and check valve failure in field pump installations. Standard inline filters require removal and disassembly to inspect. The clear view filter on the W4443DLX is inspected at a glance, without stopping work, without touching a fitting. When the filter body shows discoloration or visible debris, you clean it. Before it reaches the pump. At $549 delivered — below the cost of building an equivalent system from components — the W4443DLX is the professional’s choice when downtime is not an option.

7-Year Warranty

The W4443DLX carries Bertolini’s industry-leading 7-year warranty on the pump, backed by over 100 years of Italian engineering and millions of pumps operating globally. The thermal relief valve is covered under its respective manufacturer warranty. Contact WSHPWR for warranty support and service guidance.