SIMPSON ALH4240 4200 PSI Gas Pressure Washer – 4.0 GPM, Honda GX390 Engine, Aluminum Series

Powerful, portable, and built for professional cleaning

The SIMPSON Aluminum Series ALH4240 delivers 4200 PSI at 4.0 GPM, pairing a reliable Honda GX390 engine with a CAT triplex pump for strong, consistent cleaning results. Designed for contractor workloads, this cold-water machine emphasizes efficiency, durability, and ease of use on busy job sites.

With an ultra-lightweight aircraft-grade aluminum frame, the ALH4240 trades heavy steel for maneuverability without compromising strength. A 50-foot high-pressure hose keeps you productive across large surfaces, while the ergonomic spray gun and included 5 quick-connect nozzles let you switch from broad wash to targeted detailing in seconds. For crews that move from deck cleaning to graffiti removal, this setup offers a flexible, on-site cleaning solution that can adapt as work evolves.

Key features that support professional cleaning tasks

• 49-State compliant cold-water operation, Not for sale in California
• HONDA GX390 engine starts reliably and powers a balanced CAT triplex pump with thermal relief
• 50' dual-braided hose resists kinks and includes a non-marring jacket to protect finished surfaces
• Aircraft-grade aluminum frame keeps weight down while resisting corrosion from outdoor use
• Five quick-connect nozzles (0°, 15°, 25°, 40°, and soap) cover diverse cleaning tasks
• Professional QC spray gun with safety lock-out and an extended 16" wand for precise control

Real-world uses and practical benefits

Imagine preparing a wooden deck for restoration, rinsing a concrete driveway after staining, or removing graffiti from exterior walls. The ALH4240’s power and reach enable these tasks with fewer repositionings and interruptions, letting crews stay focused on the job at hand.

• Deck cleaning and wood restoration: effective surface prep with controlled power
• Driveways and siding: tackles tough stains, discoloration, and buildup
• Graffiti removal and paint prep: supports surface preparation and material compatibility
• Fleet and facility maintenance: helps maintain exteriors of equipment, trailers, and buildings

Ease of use, setup, and long-term value

Designed for easy assembly and straightforward starting, the ALH4240 emphasizes reliability on demanding days. The aluminum frame reduces fatigue from transport and site-to-site movement, while corrosion resistance helps preserve the unit’s appearance and performance over time. Comprehensive warranty support—10-year frame, 5-year pump, 3-year engine—offers additional peace of mind for professional buyers.

What’s included and warranty snapshot

• Pressure washer, 50' hose, spray gun, wand, five quick-connect nozzle tips
• Detergent siphon tube with filter, engine oil, quick-start setup guide, owner’s manual