RKV4037-F24VR35 | 3400 RPM High-Pressure Triplex Pump

RKV4037-F24VR35 by Annovi Reverberi — RK Series Triplex Plunger Pump with Gymatic VR35 Unloader | 4.0 GPM | 3,700 PSI | Bronze Connecting Rods | 1″ Hollow Keyway Shaft | SAE J609A Gas and Diesel Engine Drive | No Chemical Injector

The RKV4037-F24VR35 by Annovi Reverberi is a high-output RK Series triplex ceramic plunger pump engineered for gas and diesel engine-driven commercial and industrial pressure washing systems requiring 4.0 GPM at 3,700 PSI with the elevated bypass regulation capacity of the Gymatic VR35 unloader and straight high-pressure water delivery. Rated at 4.0 GPM and 3,700 PSI at 3,400 RPM, the RKV4037-F24VR35 delivers 14,800 cleaning units — combining the high-volume coverage speed of 4.0 GPM with 3,700 PSI focused impact that cuts through mud, oil, scale, and caked-on debris in fewer passes — through a reinforced crankcase with oversized crankshaft, bronze connecting rods, solid ceramic plungers, precision brass manifold, stainless steel check valves, and an F24 SAE J609A direct-drive flange for close-coupling to gasoline or diesel engines.

The RKV4037-F24VR35 is the no-injector configuration of the RKV 3,700 PSI VR35 platform — the correct choice for operators managing chemical delivery through a dedicated external system or operating on straight 3,700 PSI water output. The Gymatic VR35 (AR22287) operates with 300 PSI of headroom below its 4,000 PSI rated ceiling at 3,700 PSI — maintaining stable bypass regulation across continuous high-pressure commercial operation. For the injector variant of this platform, see the RKV4037F24VR35I.

Built by Annovi Reverberi in Modena, Italy — with US-based operations, a domestic parts distribution network, and dedicated AR North America technical support — the RKV4037-F24VR35 arrives as a complete, factory-tested assembly. Pre-filled with AR break-in oil, equipped with the factory-matched Gymatic VR35 unloader, and packaged with mounting bolts and fasteners, a vented dipstick, operator’s manual, and full parts schematic, this pump is ready to install from the moment it arrives. Protected by a 5-year US limited warranty through AR North America and built to be fully rebuilt rather than replaced, the RKV4037-F24VR35 is a long-term investment capable of a decade of productive commercial service life.

Factory-Matched and Approved — The RKV4037-F24VR35 Complete Assembly Advantage

No Mismatches. No Guesswork. No Warranty Risk. Just Install and Run.

Every RKV4037-F24VR35 ships as a factory-matched, factory-approved, and factory-installed complete pump and unloader assembly — the Gymatic VR35 unloader selected, calibrated, and installed by Annovi Reverberi specifically for this pump’s 4.0 GPM / 3,700 PSI operating point:

• Factory-matched VR35 for 3,700 PSI — the VR35 unloader on the RKV4037-F24VR35 is factory-calibrated for this pump’s specific 4.0 GPM / 3,700 PSI output. Bypass response, pressure regulation range, and adjustment characteristics are factory-set for this duty point — not carried over from a different pressure configuration.
• Factory-approved configuration — the complete RKV4037-F24VR35 assembly is validated and approved by AR North America for this duty point. Operating with the factory-installed components maintains full 5-year warranty coverage. Substituting aftermarket or lower-rated unloader components risks warranty coverage and unstable pressure behavior at 3,700 PSI.
• Factory-installed and tested — every RKV4037-F24VR35 exits the AR manufacturing facility with the VR35 unloader mounted, calibrated, and load-tested at 50%, 100%, and 150% of rated output before shipment. Verified for flow, pressure, and leak-free operation before the pump leaves the factory.
• Eliminates component mismatch returns — unloader specifications not matched to the pump’s flow rate and pressure are among the most common causes of performance problems and warranty disputes on high-output commercial builds. The factory-matched RKV4037-F24VR35 assembly eliminates this failure mode before the pump leaves the box.
• Stress-free installation — mount the pump to the engine, connect system hoses and inlet supply, add fuel, and start. The RKV4037-F24VR35 arrives engineered, assembled, and ready. No additional component sourcing, no assembly variables, no first-run surprises.

Decoding the RKV4037-F24VR35 Model Number

What Every Segment of This AR Pump Designation Tells You

• RKV — Pump series: RK Series triplex plunger pump — AR’s industrial pump platform with reinforced crankcase, oversized crankshaft, and front-access piston packing and valve serviceability
• 40 — Flow rate: 4.0 GPM per AR model code convention
• 37 — Maximum pressure: 3,700 PSI — 4.0 × 3,700 = 14,800 cleaning units
• F24 — Flange type: SAE J609A direct-drive flange — close coupling to gas or diesel engines with a 1″ I.D. cylindrical shaft (AR part AR41866)
• VR35 — Unloader system: Gymatic VR35 (AR22287) — rated to 4,000 PSI and 5 GPM. At 3,700 PSI the VR35 operates with 300 PSI of headroom below its rated ceiling — within the VR35’s rated envelope, factory-matched to this pump’s operating point.
• No trailing I suffix — model terminates at VR35, confirming straight 3,700 PSI water output without a factory-installed downstream chemical injector. For the injector variant, see the RKV4037F24VR35I.

RKV4037-F24VR35 vs RKV4037F24VR35I — The RKV 3,700 PSI VR35 Family

Both models share the same RK Series platform, F24 flange, oversized crankshaft, bronze connecting rods, and 4.0 GPM / 3,700 PSI / 14,800 CU output with the Gymatic VR35 at 300 PSI of operating headroom:

• RKV4037-F24VR35 (this model) — Gymatic VR35 (AR22287), no chemical injector. Straight 3,700 PSI water output. Correct for external chemical management or clean water applications.
• RKV4037F24VR35I — Gymatic VR35 (AR22287) with integrated I-series downstream chemical injector. Two-mode wash capability: 3,700 PSI rinse and low-pressure detergent pre-soak from a single factory-assembled unit.
• RKV4037VR35IDR — Gymatic VR35 with I-series injector and IDR Instant Dump Regulator for immediate pressure dump at trigger release. The highest specification variant for high-cycle, safety-critical applications.

Key Specifications

RKV4037-F24VR35 Technical Details at a Glance

• Flow Rate: 4.0 GPM (gallons per minute)
• Maximum Pressure: 3,700 PSI
• Cleaning Units: 14,800 (GPM × PSI)
• Operating Speed: 3,400 RPM
• Pump Type: RK Series triplex ceramic plunger pump — smooth, low-pulsation high-pressure output
• Crankshaft: Oversized — engineered for the sustained mechanical demands of 4.0 GPM / 3,700 PSI continuous commercial duty
• Manifold Material: Precision-machined brass — corrosion-resistant construction for sustained 3,700 PSI cycle integrity
• Plungers: Solid ceramic — exceptional hardness, wear resistance, and thermal shock resistance across extended commercial operating hours
• Connecting Rods: Bronze — premium fatigue strength and wear resistance at 4.0 GPM / 3,700 PSI continuous duty cycles
• Valves: Stainless steel check valves — pre-installed for reliable sealing under continuous high-pressure operation
• Serviceability: Front-access piston packings and valve assemblies; oil sight glass and vented dipstick
• Lubrication: Oil-bath crankcase for continuous bearing and journal lubrication
• Flange: F24 — SAE J609A direct-drive flange, 1″ shaft, gas and diesel engine compatible (AR part AR41866)
• Unloader System: Gymatic VR35 (AR22287) — brass body, adjustable pressure regulation, rated to 4,000 PSI and 5 GPM; 300 PSI operating headroom above 3,700 PSI output; factory-matched and factory-installed
• Chemical Injector: Not included — no factory-installed downstream injector; chemical delivery managed externally
• Warranty: 5-year limited warranty — US-based coverage through AR North America; maintained with factory-installed components

What’s Included in the Box

A Complete, Factory-Configured RKV4037-F24VR35 Assembly Ready for Installation

• Factory-matched Gymatic VR35 unloader (AR22287) — selected, calibrated, and installed by AR North America for the RKV4037-F24VR35’s 4.0 GPM / 3,700 PSI operating point; no downstream injector port on this variant
• AR factory break-in oil — crankcase pre-filled to the correct operating level for first startup
• Vented dipstick — fast, accurate crankcase oil level checks with proper crankcase pressure relief
• Clear oil sight glass — at-a-glance visual verification of crankcase lubrication level
• Stainless steel check valves and premium seals — factory-installed for reliable performance at 3,700 PSI from first startup
• Mounting bolts and fasteners — hardware sized for F24 SAE J609A direct-drive flange installation on compatible 1″ shaft gas or diesel engines
• Operator’s manual — complete installation, startup, operating, and maintenance procedures for the RKV4037-F24VR35 including oil change intervals, water supply requirements, and winterization protocol
• Parts schematic — exploded-view diagram with AR part numbers for every serviceable RKV4037-F24VR35 component
• Factory test certification — every RKV4037-F24VR35 load-tested at 50%, 100%, and 150% of rated output before leaving the AR manufacturing facility

The Gymatic VR35 — 300 PSI Headroom at 3,700 PSI. Straight Water Output.

Factory-Matched. Adjustable. Tamper-Resistant. No Injector.

The Gymatic VR35 (AR22287) on the RKV4037-F24VR35 is rated to 4,000 PSI — operating with 300 PSI of headroom above 3,700 PSI:

• 300 PSI headroom — within the VR35 rated envelope — the VR35 at 3,700 PSI operates below its rated ceiling on the RKV4037-F24VR35, maintaining stable bypass regulation at this high-pressure operating point. Bypass transitions protect hoses, spray guns, and downstream accessories at every trigger release.
• Versatile pressure adjustment — the VR35 unloader on the RKV4037-F24VR35 allows operators to dial in working pressure for different nozzle sizes, surface types, and cleaning tasks — from delicate surfaces to aggressive heavy-duty washdown — without constant nozzle changes
• Adjustable then tamper-resistant — operating pressure set on-site and locked before production, maintained consistently across every operator and every job cycle without re-adjustment or drift
• Smooth internal bypass at 4.0 GPM — trigger-off bypass smoothly redirects the full 4.0 GPM flow at 3,700 PSI, protecting the pump from dead-heading and reducing heat buildup during idle intervals on production wash jobs. Minimize extended trigger-off idle time.
• No factory-installed downstream injector — the RKV4037-F24VR35 delivers straight 3,700 PSI water output. Chemical delivery managed externally through a dedicated downstream injector, soft wash proportioner, or separate chemical system. For integrated chemical capability at this pressure point, see the RKV4037F24VR35I or RKV4037VR35IDR.
• Engine load reduction in bypass — reduced back-pressure lowers engine load and fuel consumption during trigger-off idle intervals on full-day wash operations

RK Series Construction — Built for 3,700 PSI High-Output Continuous Duty

Solid Ceramic. Precision Brass. Bronze Connecting Rods. Oversized Crankshaft. Front-Access Service.

• Solid ceramic plungers provide excellent wear and heat resistance on the RKV4037-F24VR35, protecting seals and extending service intervals in high-temperature 3,700 PSI continuous-duty environments. Individual replacement when service limits are reached.
• Bronze connecting rods and oversized crankshaft on the RKV4037-F24VR35 deliver the mechanical strength required for long hours of continuous operation at full 3,700 PSI commercial load, distributing reciprocating forces evenly for sustained duty performance
• Precision-machined brass manifold resists corrosion from water, detergents, and environmental exposure on the RKV4037-F24VR35, maintaining accurate sealing surfaces and consistent pressure performance over the pump’s service life
• Stainless steel check valves maintain tight sealing at 3,700 PSI, helping the RKV4037-F24VR35 hold its performance curve across years of high-pressure cycling
• Triplex three-plunger design produces smooth, low-pulsation flow that reduces vibration and fatigue on hoses, spray guns, and fittings throughout the wash system connected to the RKV4037-F24VR35

Front-Access Serviceability and Maintenance

Protecting the RKV4037-F24VR35 Investment Through Planned Maintenance

• Front-access piston packings and valve assemblies — packing and valve service on the RKV4037-F24VR35 is accessible with standard tools from the front of the pump without full crankcase disassembly, minimizing service time in commercial and field environments
• Oil sight glass and vented dipstick — at-a-glance oil level monitoring and simplified oil change procedures on the RKV4037-F24VR35 without removing the pump from service
• Oil service on schedule — break-in oil change at 50 hours; full service every 500 hours or 3–5 months. Clean oil and correct level protect bearings and crankshaft integrity at 3,700 PSI continuous commercial duty.
• Inlet supply must exceed 4.0 GPM — size inlet plumbing, filtration, and suction hose for the RKV4037-F24VR35’s 4.0 GPM demand to prevent cavitation-related wear at this pump’s elevated operating pressure
• Winterization is mandatory — protect the RKV4037-F24VR35 with RV-grade environmentally safe antifreeze for storage and transport in cold conditions to prevent cracked manifolds and destroyed seals

Typical Applications

Where the RKV4037-F24VR35 Delivers Best Results

• Fleet maintenance — buses, semi-trucks, delivery vans, and service vehicles in dedicated wash bays where the RKV4037-F24VR35’s 4.0 GPM volume and 3,700 PSI cleaning force handle heavy road film and grease with chemical applied through an external system
• Construction equipment cleaning — bulldozers, loaders, skid steers, and jobsite tools where 14,800 CU high-pressure output removes heavy mud, cement splatter, and hydraulic oil contamination efficiently
• Agricultural machinery washdown — tractors, combines, sprayers, and farm trailers between field cycles where 3,700 PSI penetrating impact handles compacted agricultural contamination on gas or diesel engine-powered rigs
• Industrial facilities — equipment cleaning, floor washdown, and maintenance tasks in plants, warehouses, and production areas where the RKV4037-F24VR35’s continuous-duty VR35 pressure regulation supports consistent high-output performance
• Marine services — boats, docks, and portside infrastructure where 3,700 PSI cleaning power and the RKV4037-F24VR35’s brass manifold corrosion resistance support effective cleaning in marine environments
• Mobile contractors requiring external chemical systems — truck- or trailer-mounted rigs serving industrial, agricultural, and municipal customers where the RKV4037-F24VR35’s clean water output pairs with a dedicated downstream chemical system for maximum flexibility

For operators who prefer a fully configured direct-drive system rather than a bare pump assembly, WSHPWR also carries complete gas and diesel engine pump packages ready to mount on a frame or trailer.

5-Year US Warranty, Full Rebuildability, and Wholesale Pricing

High-Output RK Series Performance Backed by Domestic Support

The RKV4037-F24VR35 is protected by Annovi Reverberi’s 5-year limited warranty through AR North America’s US-based warranty and service network. Warranty coverage is maintained by operating the RKV4037-F24VR35 with the factory-installed components and following published installation and maintenance requirements. Every internal wear component — solid ceramic plungers, bronze connecting rods, precision brass manifold seals and o-rings, stainless check valve seats and springs, Gymatic VR35 unloader service parts (AR22287), piston packing kits, and crankcase bearings — is stocked domestically through AR’s authorized distribution channels. Contractors, rental fleet operators, municipal purchasing departments, resellers, and volume buyers are invited to contact the WSHPWR wholesale team for pricing on the RKV4037-F24VR35 and the complete Annovi Reverberi pump and unloader assembly line. WSHPWR maintains one of the most complete AR North America inventories available through any US web store — with thousands of AR products in stock and a continually expanding catalog.

14,800 Cleaning Units. 3,700 PSI. 4.0 GPM. Factory-Matched VR35. Clean Water Output. No Injector.

Italian Engineering. Factory-Approved Assembly. No Mismatches. US Warranty Coverage.

For contractors, fleet operators, industrial maintenance teams, agricultural operations, and marine facility professionals who need 4.0 GPM at 3,700 PSI — in a factory-matched, factory-approved, and factory-tested complete pump and unloader assembly with Gymatic VR35 bypass regulation within its rated envelope, straight water output for external chemical management, RK Series oversized crankshaft construction with front-access serviceability, bronze connecting rods, and stress-free installation that eliminates mismatch risk and maintains full warranty coverage — the RKV4037-F24VR35 delivers a properly engineered, completely rebuildable assembly from one of the global pressure pump industry’s most trusted manufacturers. Fourteen thousand eight hundred cleaning units. Direct drive. One-inch keyway shaft. Factory-matched VR35 bypass. No fixed injector. Front-access service design. Five years of US warranty. A decade of service life.

Volume buyers, resellers, and rental fleet operators can reach the WSHPWR wholesale team directly at wholesale@wshpwr.com to discuss pricing for quantity purchases across the complete Annovi Reverberi lineup — including pumps, unloader assemblies, and service parts.